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TPS53819ARGTT

TPS53819ARGTT

  • 厂商:

    BURR-BROWN(德州仪器)

  • 封装:

    VQFN-16_3X3MM-EP

  • 描述:

    IC REG CTRLR BUCK PMBUS 16QFN

  • 数据手册
  • 价格&库存
TPS53819ARGTT 数据手册
Order Now Product Folder Support & Community Tools & Software Technical Documents Reference Design TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 TPS53819A 3-V to 28-V Input, 40-A, Eco-Mode™, D-CAP2™ Synchronous Buck Controller With PMBus™ 1 Features 2 Applications • • • • • • • • • • • 1 • • • • • • • • • • • • Conversion Input Voltage 3 V to 28 V VDD input voltage 4.5 V to 28 V Output voltage 0.6 V to 5.5 V Supports all ceramic output capacitors Reference voltage: 600 mV ±0.5% tolerance ±9% Voltage adjustment with PMBus™ Built-in 5-V LDO D-CAP2™ mode with 100-ns load-step response Auto-skip Eco-mode™ for light-load efficiency Adaptive on-time control architecture with eight selectable frequencies using PMBus Supports voltage margining using PMBus Programmable soft-start time using PMBus Programmable power-on delay using PMBus Programmable VDD UVLO level using PMBus Fault report using PMBus Pre-charged start-up capability Built-In output discharge Power-good output with programmable delay Internal overvoltage, undervoltage, and overcurrent limit protections Thermal shutdown (non-latch) 3 mm × 3 mm, 16-pin, QFN package Create a custom design using the TPS53819A with the WEBENCH® Power Designer Point-of-load power In: – Storage computers – Server computers – Multi-function printers – Embedded computing 3 Description The TPS53819A device is a small-sized, single buck controller with adaptive on-time D-CAP2 mode control and PMBus. The device is suitable for low output voltage and high current, system power rail, or similar point-of-load (POL) power supply in digital consumer products. Small package with minimal pin-count saves space on the PCB, while the programmability and fault report via PMBus simplify the power supply design. The skip-mode at light-load condition combined with strong gate drivers and low-side FET on-resistance (RDS(on)) current sensing can support low-loss and high efficiency operation, over a broad load range. The conversion input voltage, which is the high-side FET drain voltage, ranges from 3 V to 28 V. The supply voltage (VDD) is from 4.5 V to 28 V. The output voltage ranges from 0.6 V to 5.5 V. The device is available in a 16-pin, QFN package and is specified from –40°C to +85°C. Device Information(1) PART NUMBER TPS53819A PACKAGE BODY SIZE (NOM) QFN (16) 3.00 mm × 3.00 mm (1) For all available packages, see the orderable addendum at the end of the datasheet. Simplified Application VREG V3P3 VIN EN VIN CSD87350 SW VOUT 16 1 15 ADDR SCL 2 SDA 3 ALERT 4 TRIP 14 PGOOD EN 13 VBST SW 12 VIN SW TG SW TGR BG DRVH 11 TPS53819A DRVL 10 VO FB GND VDD VREG 5 6 7 8 9 PGND VDD UDG-12118 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com Table of Contents 1 2 3 4 5 6 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Pin Configuration and Functions ......................... Specifications......................................................... 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 7 1 1 1 2 3 4 Absolute Maximum Ratings ...................................... 4 ESD Ratings ............................................................ 4 Recommended Operating Conditions....................... 4 Thermal Information .................................................. 5 Electrical Characteristics........................................... 5 Timing Requirements ................................................ 8 Switching Characteristics .......................................... 9 Typical Characteristics ............................................ 10 Detailed Description ............................................ 16 7.1 Overview ................................................................. 16 7.2 Functional Block Diagram ....................................... 16 7.3 Feature Description................................................. 17 7.4 Device Functional Modes........................................ 19 7.5 Programming........................................................... 21 7.6 Register Maps ........................................................ 24 8 Application and Implementation ........................ 34 8.1 Application Information............................................ 34 8.2 Typical Application ................................................. 34 9 Power Supply Recommendations...................... 40 10 Layout................................................................... 41 10.1 Layout Guidelines ................................................. 41 10.2 Layout Example .................................................... 42 11 Device and Documentation Support ................. 44 11.1 11.2 11.3 11.4 11.5 11.6 Device Support...................................................... Receiving Notification of Documentation Updates Community Resources.......................................... Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 44 44 44 44 44 44 12 Mechanical, Packaging, and Orderable Information ........................................................... 45 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision A (October 2015) to Revision B • Added links for Webench; editorial updates - no changes to technical data ......................................................................... 1 Changes from Original (November 2012) to Revision A • 2 Page Page Added ESD Ratings table, Feature Description section, Device Functional Modes section, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section ............................................................... 1 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 5 Pin Configuration and Functions SCL 1 SDA 2 ADDR PGOOD EN VBST RGT Package 16 Pin QFN Top View 16 15 14 13 12 SW 11 DRVH TPS53819A TRIP 4 9 VREG 5 6 7 8 VDD DRVL GND 10 FB 3 VO ALERT Pin Functions PIN I/O (1) DESCRIPTION NAME NO. ADDR 16 I PMBus address configuration. Connect this pin to a resistor divider between VREG and GND to program different address settings. (See Table 2 for details.) ALERT 3 O Open-drain alert output for the PMBus interface. DRVH 11 O High-side MOSFET floating driver output that is referenced to SW node. The gate drive voltage is defined by the voltage across bootstrap capacitor between VBST and SW. DRVL 10 O Synchronous MOSFET driver output that is referenced to GND. The gate drive voltage is defined by VREG voltage. EN 14 I Enable pin that can turn on the DC/DC switching converter. EN pin works in conjunction with the CP bit in PMBus ON_OFF_CONFIG register. FB 6 I Output voltage feedback input. Connect this pin to a resistor divider between output voltage and GND. GND 7 G Ground pin. PGOOD 15 O Open drain power good status signal. Provides start-up delay time after FB voltage falls within specified limits. After FB voltage goes out of specified limits, PGOOD goes low within 2 µs. SCL 1 I Clock input for the PMBus interface. SDA 2 I/O SW 12 P TRIP 4 I/O VBST 13 P Supply rail for high-side gate driver (boost terminal). Connect bootstrap capacitor from this pin to SW node. Internally connected to VREG via bootstrap PMOS switch. VDD 8 P Controller power supply input. VO 5 I Output voltage. VREG 9 P 5-V low-drop-out (LDO) output. Supplies the internal analog and driver circuitry. (1) Data I/O for the PMBus interface. Output switching terminal of power converter. Connect this pin to the output inductor. OCL detection threshold setting pin. A 10-µA current with a TC of 4700ppm/°C is sourced out of the TRIP pin and is used to set the OCL trip voltage as follows: VOCL= VTRIP/8 and ( VTRIP ≤ 3 V, VOCL ≤ 375 mV) I=Input, O=Output, P=Power, G=Ground Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 3 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 6 Specifications 6.1 Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted) (1) Input voltage (2) MIN MAX VBST –0.3 38 VBST (3) –0.3 6 EN –0.3 7.7 VO, FB, SCL, SDA, ADDR –0.3 6 VDD –0.3 30 –3 32 Pulse < 30% of the repetitive period –5 32 DC –3 38 Pulse < 30% of the repetitive period –5 38 DRVH (3), DRVL –0.3 6 ALERT, VREG, TRIP –0.3 6 PGOOD –0.3 DRVH Output voltage (2) Storage temperature, Tstg (2) (3) V 7.7 Junction temperature, TJ (1) V DC SW UNIT –55 150 °C 150 °C Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. All voltage values are with respect to the network ground terminal unless otherwise noted. Voltage values are with respect to the SW terminal. 6.2 ESD Ratings VALUE V(ESD) (1) (2) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1) ±2000 Charged-device model (CDM), per JEDEC specification JESD22-C101 (2) ±500 UNIT V JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.. JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process. 6.3 Recommended Operating Conditions over operating free-air temperature range (unless otherwise noted) MIN Input voltage range –0.1 35.5 VBST (1) –0.1 5.5 EN –0.1 6.5 VO, FB, SCL, SDA, ADDR –0.1 5.5 4.5 28 –3 30 –4.5 30 SW DC Pulse < 30% of the repetitive period DC V V –3 35.5 35.5 DRVH (1), DRVL –0.1 5.5 V ALERT, VREG –0.1 5.5 V PGOOD –0.1 6.5 V –40 85 °C Pulse < 30% of the repetitive period Operating free-air temperature, TA 4 UNIT –4.5 DRVH (1) MAX VBST VDD Output voltage range NOM V Voltage values are with respect to the SW terminal. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 6.4 Thermal Information TPS53819A THERMAL METRIC (1) RGT (QFN) UNIT 16 PINS RθJA Junction-to-ambient thermal resistance 51.3 °C/W RθJC(top) Junction-to-case (top) thermal resistance 85.4 °C/W RθJB Junction-to-board thermal resistance 20.1 °C/W ψJT Junction-to-top characterization parameter 1.3 °C/W ψJB Junction-to-board characterization parameter 19.4 °C/W RθJC(bot) Junction-to-case (bottom) thermal resistance 6.0 °C/W (1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953. 6.5 Electrical Characteristics over operating free-air temperature range, VVREG = 5 V, VEN = 5 V (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT SUPPLY CURRENT IVDD VDD bias current TA = 25°C, no load, power conversion enabled (no switching) 920 μA IVDDSTBY VDD standby current TA = 25°C, no load, power conversion disabled 610 μA 600 mV INTERNAL REFERENCE AND FEEDBACK REGULATION VOLTAGE VFB Feedback regulation voltage FB w/r/t GND, CCM condition VFBTOL Feedback voltage tolerance FB w/r/t GND, 0°C ≤ TJ ≤ 85°C 597 VDACTOL1 DAC voltage tolerance 1 FB w/r/t GND, 0°C ≤ TA ≤ 85°C, all settings with VOUT_ADJUSTMENT only VDACTOL2 DAC voltage tolerance 2 603 mV –4.8 4.8 mV FB w/r/t GND, 0°C ≤ TA ≤ 85°C, all settings with VOUT_MARGIN only –4.8 4.8 mV DAC voltage tolerance 3 FB w/r/t GND, 0°C ≤ TA ≤ 85°C, with VOUT_ADJUSTMENT = 0Dh and VOUT_MARGIN = 70h for +5% –4.8 4.8 mV VDACTOL4 DAC voltage tolerance 4 FB w/r/t GND, 0°C ≤ TA ≤ 85°C, with VOUT_ADJUSTMENT = 13h and VOUT_MARGIN = 07h for -5% –4.8 4.8 mV VIOS_LPCMP Loop comparator input offset voltage VREF to VFB, TA = 25°C –2.5 2.5 mV IFB FB pin input current VFB = 600 mV –1 1 μA VO discharge current VVO = 0.5 V, power conversion disabled 10 VDACTOL3 600 OUTPUT VOLTAGE IVODIS 12 mA DRIVER RDRVH RDRVL DRVH resistance DRVL resistance Source, IDRVH = 50 mA 1.6 Sink, IDRVH = 50 mA 0.6 Source, IDRVL = 50 mA 0.9 Sink, IDRVL = 50 mA 0.5 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A Ω 5 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com Electrical Characteristics (continued) over operating free-air temperature range, VVREG = 5 V, VEN = 5 V (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT 0.1 0.2 V 0.01 1.5 μA 0.5 V INTERNAL BOOT STRAP SWITCH VF Forward voltage VVREG-VBST, TA = 25°C, IF = 10 mA IVBST VBST leakage current TA = 25°C, VVBST = 33 V, VSW = 28 V ENABLE LOGIC THRESHOLD VL EN low-level voltage VH EN high-level voltage VHYST EN hysteresis voltage ILEAK EN input leakage current 1.8 V 0.22 V -1 0 1 PGOOD in from higher 105% 108% 111% PGOOD in from lower 89% 92% 95% PGOOD out to higher 113% 116% 119% PGOOD out to lower 81% 84% 87% μA POWER GOOD COMPARATOR VPGTH Powergood threshold IPG PGOOD sink current VPGOOD = 0.5 V IPGLK PGOOD leakage current VPGOOD = 5.0 V 6.9 mA -1 0 1 μA 9 10 11 μA CURRENT DETECTION ITRIP TRIP source current TA = 25°C, VTRIP = 0.4 V, RDS(on) sensing TCITRIP TRIP source current temperature coefficient (1) RDS(on) sensing VTRIP TRIP voltage range RDS(on) sensing 0.2 VTRIP = 3.0 V, RDS(on) sensing 360 375 390 Positive current limit threshold VTRIP = 1.6 V, RDS(on) sensing 190 200 210 VTRIP = 0.2 V, RDS(on) sensing 20 25 30 VTRIP = 3.0 V, RDS(on) sensing –390 –375 –360 VTRIP = 1.6 V, RDS(on) sensing –212 –200 –188 VTRIP = 0.2 V, RDS(on) sensing –30 –25 –20 VOCLP Negative current limit threshold VOCLN VZC 4700 Zero cross detection offset ppm/°C 3 0 V mV mV mV PROTECTIONS VVREGUVLO VREG UVLO threshold voltage Wake-up 3.32 Shutdown 3.11 VOVP OVP threshold voltage OVP detect voltage tOVPDLY OVP propagation delay time With 100-mV overdrive VUVP UVP threshold voltage UVP detect voltage 117% 120% 65% 68% V 123% 430 ns 71% THERMAL SHUTDOWN TSDN Thermal shutdown threshold Shutdown temperature 140 Hysteresis °C 40 LDO VOLTAGE VREG LDO output voltage VIN = 12 V, ILOAD = 10 mA VDOVREG LDO low droop drop-out voltage VIN = 4.5 V, ILOAD = 30 mA, TA = 25°C ILDO(max) (1) 6 LDO overcurrent limit (1) VIN = 12 V, TA = 25°C 4.5 5 152 5.5 V 365 mV mA Specified by design. Not production tested. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Electrical Characteristics (continued) over operating free-air temperature range, VVREG = 5 V, VEN = 5 V (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT VDD UVLO VOLTAGE VDDINUVLO = 0xx VDDINUVLO = 101 VDDUVLO VDD UVLO voltage VDDHY-UVLO VDD UVLO hysteresis voltage 0°C ≤ TJ ≤ 85°C 10.2 4.1 4.25 VDDINUVLO = 110 6.0 VDDINUVLO = 111 8.1 4.4 V 0.2 V PMBus SCL and SDA INPUT BUFFER LOGIC THRESHOLDS VIL-PMBUS SCL and SDA low-level input voltage (1) 0°C ≤ TJ ≤ 85°C VIH-PMBUS SCL and SDA high-level input voltage (1) 0°C ≤ TJ ≤ 85°C VHY-PMBUS SCL and SDA hysteresis voltage (1) 0°C ≤ TJ ≤ 85°C 0.8 V 2.1 V 240 mV PMBus SDA and ALERT OUTPUT PULLDOWN VOL1-PMBUS SDA and ALERT low-level output voltage (1) VDDPMBus = 5.5 V, RPULLUP = 1.1 kΩ, 0°C ≤ TJ ≤ 85°C 0.4 V VOL2-PMBUS SDA and ALERT low-level output voltage (1) VDDPMBus = 3.6 V, RPULLUP = 0.7 kΩ, 0°C ≤ TJ ≤ 85°C 0.4 V Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 7 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 6.6 Timing Requirements MIN NOM MAX UNIT POWER-ON DELAY tPODLY Power-on delay time Delay from enable to switching POD = 000 356 μs Delay from enable to switching POD = 001 612 μs Delay from enable to switching POD = 010 1.124 ms Delay from enable to switching POD = 011 2.148 ms Delay from enable to switching POD = 100 4.196 ms Delay from enable to switching POD = 101 8.292 ms Delay from enable to switching POD = 110 16.48 ms Delay from enable to switching POD = 111 32.86 ms PGOOD DELAY tPGDLY PGOOD delay time Delay for PGOOD going in PGD = 000 165 256 320 μs Delay for PGOOD going in PGD = 001 409 512 614 μs Delay for PGOOD going in PGD = 010 0.819 1.024 1.228 ms Delay for PGOOD going in PGD = 011 1.638 2.048 2.458 ms Delay for PGOOD going in PGD = 100 3.276 4.096 4.915 ms Delay for PGOOD going in PGD = 101 6.553 8.192 9.83 ms Delay for PGOOD going in PGD = 110 13.104 16.38 19.656 ms Delay for PGOOD going in PGD = 111 105 131 157 ms 2 μs Delay for PGOOD coming out SOFT START TIME tSS Soft-start time SST = 00 1.0 SST = 01 2.0 SST = 10 4.0 SST = 11 8.0 DRVH falling to rising 320 ns DRVH rising to falling 60 ns 1 ms ms FREQUENCY CONTROL tOFF(min) tON(min) Minimum off-time Minimum on-time (1) PROTECTIONS tUVPDLY UVP filterdelay time DRIVER tDEAD (1) 8 Dead time DRVH-off to DRVL-on 10 DRVL-off to DRVH-on 20 ns Specified by design. Not production tested. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 6.7 Switching Characteristics over operating free-air temperature range VIN = 12 V, VVO = 3.3 V(unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT FREQUENCY CONTROL fSW VO pin switching frequency FS = 000 275 FS = 001 325 FS = 010 425 FS = 011 525 FS = 100 625 FS = 101 750 FS = 110 850 FS = 111 1000 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A kHz 9 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 1400 800 1200 700 Shutdown Current (µA) Supply Current (µA) 6.8 Typical Characteristics 1000 800 600 400 No Load VEN = 5 V VVDD = 12 V 200 0 −40 −25 −10 5 20 35 50 65 Temperature (°C) 80 95 500 400 300 200 No Load VEN = 0 V VVDD = 12 V 100 0 −40 −25 −10 110 125 20 35 50 65 Temperature (°C) 80 95 110 125 G002 Figure 2. VDD Shutdown Current vs Temperature 140 16 120 14 TRIP Current (µA) 100 80 60 40 12 10 8 6 4 20 OVP UVP 0 −40 −25 −10 5 20 35 50 65 Temperature (°C) 80 95 2 VVDD = 12 V 110 125 0 −40 −25 −10 G003 Figure 3. OVP/UVP Thresholds vs Temperature VIN = 12 V, V OUT = 1.2 V, I OUT = 0 A, 425 kHz, DCM 5 20 35 50 65 Temperature (°C) 80 95 110 125 G004 Figure 4. TRIP Pin Current vs Temperature VIN = 12 V, V OUT = 1.2 V, I OUT = 0 A, 425 kHz, FCCM EN (5 V/div) EN (5 V/div) VOUT (0.5 V/div) VOUT (0.5 V/div) SW (10 V/div) SW (10 V/div) PGOOD (5 V/div) PGOOD (5 V/div) Time (0.4 ms/div) Time (0.4 ms/div) Figure 5. No-Load Start-Up Waveforms with DCM 10 5 G001 Figure 1. VDD Supply Current vs Temperature OVP/UVP Threshold (%) 600 Figure 6. No-Load Start-Up Waveforms with FCCM Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Typical Characteristics (continued) VIN = 12 V, V OUT = 1.2 V, I OUT = 0 A, 425 kHz, DCM VIN = 12 V, V OUT = 1.2 V, I OUT = 20 A, 425 kHz EN (5 V/div) EN (5 V/div) VOUT (0.5 V/div) 0.5 V pre-biased VOUT (0.5 V/div) SW (10 V/div) SW (10 V/div) PGOOD (5 V/div) PGOOD (5 V/div) Time (0.4 ms/div) Time (0.4 ms/div) Figure 7. Full-Load Start-Up Waveforms Figure 8. Pre-Bias Start-Up Waveforms with DCM VIN = 12 V, V OUT = 1.2 V, I OUT = 0 A, 425 kHz, DCM VIN = 12 V, V OUT = 1.2 V, I OUT = 0 A, 425 kHz, FCCM EN (5 V/div) EN (5 V/div) VOUT (0.5 V/div) VOUT (0.5 V/div) 0.5 V pre-biased SW (10 V/div) SW (10 V/div) PGOOD (5 V/div) PGOOD (5 V/div) Time (0.4 ms/div) Time (4 ms/div) Figure 9. Pre-Bias Start-Up Waveforms with FCCM VIN = 12 V, V OUT = 1.2 V, I OUT = 0 A, 425 kHz, FCCM Figure 10. No-Load Shutdown Waveforms with DCM VIN = 12 V, V OUT = 1.2 V, I OUT = 20 A, 425 kHz, EN (5 V/div) EN (5 V/div) VOUT (0.5 V/div) VOUT (0.5 V/div) SW (10 V/div) SW (10 V/div) PGOOD (5 V/div) PGOOD (5 V/div) Time (4 ms/div) Time (40 µs/div) Figure 11. No-Load Shutdown Waveforms with FCCM Figure 12. Full-Load Shutdown Waveforms Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 11 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com Typical Characteristics (continued) VIN = 12 V, V OUT = 1.2 V IOUT = 0 A 425 kHz, DCM VIN = 12 V, V OUT = 1.2 V IOUT = 20 A, 425 kHz VIN (5 V/div) VIN (5 V/div) VOUT (0.5 V/div) VOUT (0.5 V/div) VREG (5 V/div) VREG (5 V/div) PGOOD (5 V/div) PGOOD (5 V/div) Time (2 ms/div) Time (2 ms/div) Figure 13. No-Load UVLO Start-Up Waveforms Figure 14. Full-Load UVLO Start-Up Waveforms VIN = 12 V, V OUT = 1.2 V IOUT = 0 A, 425 kHz, FCCM VIN = 12 V, V OUT = 1.2 V IOUT = 0 A, 425 kHz, DCM VOUT (50 mV/div) VOUT (50 mV/div) SW (10 V/div) SW (10 V/div) IL (5 A/div) IL (5 A/div) Time (1 µs/div) Time (2 µs/div) Figure 15. 1.2-V Output Ripple with FCCM Figure 16. 1.2-V Output Ripple with DCM VIN = 12 V, V OUT = 1.2 V, 425 kHz , DCM VIN = 12 V, V OUT = 1.2 V, 425 kHz, DCM VOUT (50 mV/div) VOUT (50 mV/div) SW (10 V/div) SW (10 V/div) IL (5 A/div) IL (5 A/div) Time (0.1 ms/div) Time (0.1 ms/div) Figure 17. CCM to DCM Transitions 12 Submit Documentation Feedback Figure 18. DCM to CCM Transitions Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Typical Characteristics (continued) VIN = 12 V, V OUT = 1.2 V, 425 kHz, DCM IOUT from 0 A to 10 A, 2.5 A/ µs VIN = 12 V, V OUT = 1.2 V, 425 kHz, FCCM IOUT from 0 A to 10 A, 2.5 A/ µs VOUT (50 mV/div) VOUT (50 mV/div) IOUT (5 A/div) IOUT (5 A/div) Time (0.1 ms/div) Time (0.1 ms/div) Figure 19. FCCM Load Transients VOUT (1 V/div) VIN = 12 V, V OUT = 1.2 V, 425 kHz IOUT = 20 A then short output, Hiccup Figure 20. DCM Load Transients VOUT (1 V/div) SW (10 V/div) SW (10 V/div) IL (10 A/div) IL (10 A/div) PGOOD (5 V/div) PGOOD (5 V/div) Time (10 ms/div) VIN = 12 V, V OUT = 1.2 V, 425 kHz IOUT = 20 A then short output, Latch -off Time (10 ms/div) Figure 21. Output Short Circuit Protection with Hiccup VIN = 12 V, V OUT = 1.2 V, I OUT = 0 A, 425 kHz, DCM VOA from 0 % to +9 % SCL (5 V/div) Figure 22. Output Short Circuit Protection with Latch-off VIN = 12 V, V OUT = 1.2 V, I OUT = 20 A, 425 kHz VOA from 0 % to +9 % SCL (5 V/div) VOUT (100 mV/div) VOUT (100 mV/div) IL (5 A/div) IL (5 A/div) PGOOD (5 V/div) PGOOD (5 V/div) Time (40 ms/div) Time (40 ms/div) Figure 23. No-Load VOUT Adjustment Waveforms Figure 24. Full-Load VOUT Adjustment Waveforms Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 13 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com Typical Characteristics (continued) 1000 100 fSET = 425 kHz VIN = 12 V VOUT = 1.2 V 10 Frequency (kHz) Frequency (kHz) 1000 100 fSET = 625 kHz VIN = 12 V VOUT = 1.2 V 10 FCCM DCM 1 0.01 0.1 1 Output Current (A) 10 FCCM DCM 1 0.01 100 Figure 25. Switching Frequency vs. Output Current 1 Output Current (A) 10 100 G001 Figure 26. Switching Frequency vs. Output Current 1000 100 fSET = 750 kHz VIN = 12 V VOUT = 1.2 V 10 Frequency (kHz) 1000 Frequency (kHz) 0.1 G005 100 fSET = 1 MHz VIN = 12 V VOUT = 1.2 V 10 FCCM DCM 1 0.01 0.1 1 Output Current (A) 10 FCCM DCM 1 0.01 100 Figure 27. Switching Frequency vs. Output Current VOUT = 1.2 V fSW = 425 kHz 100 G001 1.210 1.205 1.200 1.195 1.190 DCM, IOUT = 0 A FCCM, IOUT = 0 A DCM, IOUT = 15 A 1.185 5 6 7 VIN = 12 V VOUT = 1.2 V fSW = 425 kHz 1.215 Output Voltage (V) Output Voltage (V) 10 1.220 1.215 8 9 10 11 Input Voltage (V) 12 13 1.210 1.205 1.200 1.195 1.190 FCCM DCM 1.185 14 1.180 0 G000 Figure 29. Output Voltage vs. Input Voltage 14 1 Output Current (A) Figure 28. Switching Frequency vs. Output Current 1.220 1.180 0.1 G001 2 4 6 8 10 12 14 Output Current (A) 16 18 20 G000 Figure 30. Output Voltage vs. Output Current Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 100 100 90 90 80 80 70 70 Efficiency (%) Efficiency (%) Typical Characteristics (continued) 60 50 40 30 60 50 40 30 VOUT = 0.6 V VOUT = 1.2 V VOUT = 1.8 V DCM VIN = 12 V fSW = 425 kHz 20 10 0 VIN = 12 V VOUT = 1.2 V 0 2 4 6 8 10 12 14 Output Current (A) 16 18 fSW = 625 kHz, FCCM fSW = 425 kHz, FCCM fSW = 625 kHz, DCM fSW = 425 kHz, DCM 20 10 20 0 0.01 G000 Figure 31. Efficiency vs. Output Current 0.1 1 Output Current (A) 10 Product Folder Links: TPS53819A G001 Figure 32. Efficiency vs. Output Current Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated 100 15 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 7 Detailed Description 7.1 Overview The TPS53819A is a high-efficiency, single-channel, synchronous buck regulator controller that uses the PMBus protocol. It is suitable for low output voltage, point-of-load applications in computing and similar digital consumer applications. The device features proprietary D-CAP2 mode control combined with adaptive on-time architecture. This combination is ideal for building modern low duty-ratio and ultra-fast load step response DC-DC converters. The output voltage ranges from 0.6 V to 5.5 V. The conversion input voltage range is from 3 V to 28 V. The DCAP2 mode uses emulated current information to control the loop modulation. One advantage of this control scheme is that it does not require an external phase compensation network, which makes it easy to use. It also allows for a low external component count. The switching frequency is selectable from eight preset values through the PMBus interface. Adaptive on-time control tracks the preset switching frequency over a wide range of input and output voltages while increasing the switching frequency as needed during load step transient. 7.2 Functional Block Diagram VREF – 32% VREF +8/16% UV + PGOOD + Delay + OV + VREF –8/16% VREF +20% VBST Control Logic Enable/SS Control FB TM D-CAP2 Ramp Generator SDA VOUT SW XCON Reference Generator Adjustment / Margining SCL DRVH + + VREF VOUT VO PWM + EN PMBus Interface tON OneShot ALERT ADDR Address Detector LDO Regulator DCM / FCCM VDD VREG 10 ?A x(-1/8) TRIP x(1/8) + OCP + DRVL GND ZC TPS53819 A UDG-12119 16 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 7.3 Feature Description 7.3.1 Enable and Soft-Start When the EN pin voltage rises above the enable threshold voltage and/or ON_OFF bit is set via PMBus according to the setting in OPERATION command, the controller enters a start-up sequence. After a programmed power-on-delay duration from 0.35 ms to 32.86 ms, the internal DAC starts ramping up the reference voltage from 0 V to a target voltage (typically 0.6 V) with the programmed soft-start time from 1 ms to 8 ms. The device maintains a smooth and constant output voltage ramp-up during start-up regardless of load current. 7.3.2 Adaptive On-Time Control The TPS53819A does not have a dedicated oscillator. The device operates with a pseudo-constant frequency by feed-forwarding the input and output voltages into the on-time one-shot timer. The adaptive on-time control adjusts the on-time to be inversely proportional to the input voltage and proportional to the output voltage (tON ∝ VOUT/VIN). This makes the switching frequency fairly constant in steady state conditions over a wide input voltage range. The switching frequency is selectable from 275 kHz to 1 MHz via PMBus (FREQUENCY_CONFIG). 7.3.3 Zero Crossing Detection The TPS53819A uses a low offset comparator to detect SW node zero crossing event in order to optimize turnoff timing of low-side MOSFET. 7.3.4 Output Discharge Control When the EN pin voltage falls below the enable threshold voltage and/or ON_OFF bit is reset via PMBus according to the setting in OPERATION command, the TPS53819A discharges output capacitor using internal MOSFET connected between the VOUT pin and the GND pin while the high-side and low-side MOSFETs are maintained in the OFF state. The typical discharge resistance is 40 Ω. 7.3.5 Low-Side Driver The low-side driver is designed to drive high-current, low-RDS(on), N-channel MOSFETs. The drive capability is represented by the internal resistance, which is 0.9 Ω for VREG to DRVL and 0.5 Ω for DRVL to GND. A deadtime period to prevent shoot through is internally generated between high-side MOSFET OFF to low-side MOSFET ON, and low-side MOSFET OFF to high-side MOSFET ON. The 5-V, VREG supply voltage delivers the bias voltage. A bypass capacitor connected between the VREG and GND pins supplies the instantaneous drive current. Equation 1 shows the average low-side gate drive current. IGL = CGL ´ VVDRV ´ fSW (1) 7.3.6 High-Side Driver The high-side driver drives high current, low RDS(on) , N-channel MOSFETs. When configured as a floating driver, the VREG pin supply delivers the bias voltage. Equation 2 shows the average high-side gate current. IGH = CGH ´ VVDRV ´ fSW (2) The flying capacitor between the VBST and SW pins supplies the instantaneous drive current. The internal resistance, which is 1.6 Ω for VBST to DRVH and 0.6 Ω for DRVH to SW represents the drive capability. Equation 3 calculates the driver power dissipation required for the TPS53819A PDRV = (IGL + IGH )´ VVDRV (3) 7.3.7 Power Good The TPS53819A indicates the switcher output is within the target range when the power-good output is high. The power-good function activates after the soft-start operation has finished. If the output voltage comes within ±8% of the target value, internal comparators detect power-good state and the power-good signal becomes high after a programmed delay time between 0.25 ms and 131 ms. If the output voltage goes outside of ±16% of the target value, the power-good signal becomes low after a 2-μs internal delay. The power-good output is an open drain output and must be pulled up externally. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 17 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com Feature Description (continued) 7.3.8 Current Sense and Overcurrent Protection TPS53819A has cycle-by-cycle overcurrent limiting control. The inductor current is monitored during the OFF state and the controller maintains the OFF state during the period when inductor current is larger than the overcurrent trip level. In order to provide both good accuracy and cost effective solution, TPS53819A supports temperature compensated MOSFET on-resistance (RDS(on)) sensing. The TRIP pin should be connected to GND through the trip voltage setting resistor, RTRIP. The TRIP terminal sources ITRIP current, which is 10 μA typically at room temperature, and the trip level is set to the OCL trip voltage VTRIP as shown in Equation 4. Note that the VTRIP is limited up to approximately 3 V internally. VTRIP (mV ) = RTRIP (kW )´ ITRIP (mA ) (4) The inductor current is monitored by the voltage between GND pin and SW pin so that SW pin should be properly connected to the drain terminal of the low-side MOSFET. The TRIP current has a 4700-ppm/°C temperature slope to compensate the temperature dependency of the on-resistance. The device uses the GND pin as the positive current sensing node. As the comparison occurs during the OFF state, VTRIP sets the valley level of the inductor current. Thus, the average load current at the overcurrent threshold, IOCP, is calculated as shown in Equation 5. IOCP = VTRIP (8 ´ RDS(on) ) + IIND(ripple) 2 = VTRIP (8 ´ RDS(on) ) + (VIN - VOUT )´ VOUT 1 ´ 2 ´ L ´ fSW VIN (5) In an overcurrent condition, the load current exceeds the inductor current delivered to the output capacitor, thus the output voltage tends to fall. Eventually, it crosses the undervoltage protection threshold and the device shuts down. If hiccup mode is selected, then after a hiccup delay time (8.96 ms + 7× programmed soft-start time), the controller restarts. If the overcurrent condition remains, the procedure is repeated and the device enters hiccup mode. During the CCM, the negative current limit (NCL) protects the external FET from carrying too much current. The OCLN detect threshold is set at the same absolute value as positive current limit (OCLP) but with negative polarity. Note that the threshold still represents the valley value of the inductor current. When an OCLP or OCLN event occurs, the corresponding fault signals (IOUT_OC and IOUT) of the STATUS_WORD register is latched to indicate the faults and can be read via PMBus. 7.3.9 Overvoltage and Undervoltage Protection TPS53819A monitors a resistor divided feedback voltage to detect overvoltage and undervoltage conditions. When the feedback voltage becomes lower than 68% of the target voltage, the undervoltage protection (UVP) comparator output goes high and an internal UVP delay time counter begins counting. After 1 ms, the device turns OFF both high-side and low-side MOSFETs drivers. If the hiccup mode is selected, then the controller restarts after a hiccup delay time (8.96 ms + 7 × programmed soft-start time). This function is enabled after the soft-start operation is completed. When the feedback voltage becomes higher than 120% of the target voltage, the overvoltage protection (OVP) comparator output goes high and the circuit latches OFF the high-side MOSFET driver and latches ON the low-side MOSFET driver. If the sensed inductor current reaches the negative current limit, then the low-side MOSFET driver is turned OFF, and high-side MOSFET driver is turned ON with an appropriate on-time to limit the inductor current while the output voltage discharges. 7.3.10 Out-of-Bound Protection TPS53819A has an out-of-bound (OOB) overvoltage protection that tries to protect the output load at a much lower overvoltage threshold of 8% above the target voltage. OOB protection does not trigger an overvoltage fault, so the device is not latched off after an OOB event. OOB protection is intended as an early no-fault overvoltage protection mechanism, in addition to the official overvoltage protection as described in the Overvoltage and Undervoltage Protection section. 7.3.11 UVLO Protection The TPS53819A has VDD undervoltage lockout protection (UVLO). When the VDD voltage is lower than the programmed UVLO threshold voltage, the switch mode power supply shuts OFF. This is a non-latch protection, but if VDD UVLO occurs when the switcher is enabled by either EN pin or ON_OFF bit via PMBus, the corresponding fault signals (VIN_UV and INPUT) of the STATUS_WORD register latch off to indicate the fault condition, and can be read via PMBus. 18 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Feature Description (continued) 7.3.12 Thermal Shutdown The TPS53819A has an over-temperature protection feature. If the temperature exceeds the threshold value (typically 140°C), the device is shut OFF. This is a non-latch protection, but when the temperature exceeds the threshold value, the corresponding fault signal (TEMP) of the STATUS_WORD register latches off to indicate the fault condition, and can be read via PMBus. 7.4 Device Functional Modes 7.4.1 Light-Load Condition in Auto-Skip Operation (Eco-mode) If the discontinuous conduction mode (DCM) is selected via PMBus (MODE_SOFT_START_CONFIG), TPS53819A automatically reduces the switching frequency at light-load conditions to maintain high efficiency. Specifically, as the output current decreases from heavy load condition, the inductor current is also reduced and eventually comes to the point that its ripple valley current touches zero level, which is the boundary between continuous conduction mode (CCM) and discontinuous conduction mode (DCM). The synchronous MOSFET is turned OFF when this zero inductor current is detected. As the load current further decreases, the converter runs into DCM. NOTE The zero current must be detected for at least 16 switching cycles to switch from CCM to DCM. The on-time remains almost the same as continuous conduction mode so that it takes longer time to discharge the output capacitor with smaller load current to the reference voltage level. The transition point to the light-load operation IOUT(LL) (i.e., the threshold between continuous and discontinuous conduction mode) is calculated in Equation 6. IOUT(LL ) = (VIN - VOUT )´ VOUT 1 ´ 2 ´ L ´ fSW VIN where • fSW is the PWM switching frequency (6) Switching frequency versus output current in the light-load condition is a function of L, VIN and VOUT, but it decreases almost proportionally to the output current when below the IOUT(LL) given in Equation 6. For example, it is 65 kHz at IO(LL)/5 if the frequency setting is 325 kHz. 7.4.2 Forced Continuous Conduction Mode When the forced continuous conduction mode (FCCM) is selected via PMBus (MODE_SOFT_START_CONFIG), the controller maintains continuous conduction mode even in light-load condition. In FCCM mode, switching frequency maintains a constant level over the entire load range which is suitable for applications that need tight control of the switching frequency at a cost of lower efficiency. During the soft-start time, the controller maintains discontinuous conduction mode, and then switches to continuous conduction mode if FCCM is selected after the soft-start operation is completed. 7.4.3 D-CAP2™ Mode From small-signal loop analysis, a buck converter using D-CAP2™ mode control architecture can be simplified as shown in Figure 33. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 19 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com Device Functional Modes (continued) VO C C1 C C2 SW RC1 R C2 VIN R FBH G DRVH FB + + R FBL + + 0.6 V VOFS Lx Control Logic and Driver DRVL VOUT ESR TPS53819A R LOAD COUT UDG-12120 Figure 33. Simplified Modulator Using D-CAP2™ Control Architecture The D-CAP2 control architecture in TPS53819A includes an internal ripple generation network enabling the use of very low-ESR output capacitors such as multi-layer ceramic capacitors (MLCC). No external current sensing networks or compensators are required with D-CAP2 control architecture in order to simplify the power supply design. The role of the internal ripple generation network is to emulate the ripple component of the inductor current information and then combine it with the voltage feedback signal. VOFS is the internal offset to compensate the offset caused by the internal ripple, and the typical VOFS value is 4 mV. The 0-dB frequency of the D-CAP2 architecture can be approximated as shown in Equation 7. f0 = RC1 ´ CC1 ´ 0.6 ´ (0.67 + D ) 2p ´ G ´ L X ´ COUT ´ VOUT where • • G is gain of the amplifier which amplifies the ripple current information generated by the network D is the duty ratio (7) The typical G value is 0.25. The RC1CC1 time constant value varies according to the selected switching frequency as shown in Table 1. Table 1. Switching Frequency Selection SWITCHING FREQUENCY (kHz) RC1CC1 TIME CONSTANT (µs) 275 325 425 525 625 750 850 1000 20 Submit Documentation Feedback 75 62 48 36 Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 In order to secure enough phase margin, consider that f0 should be lower than 1/3 of the switching frequency, but is also higher than 5 times the fC2 as shown in Equation 8. f 5 ´ fC2 £ f0 £ SW 3 where • fC2 is determined by the internal network of RC2 and CC2 (1.4 kHz typ) (8) This example describes a DC-DC converter with an input voltage range of 12-V and an output voltage of 1.2-V. If the switching frequency is 525 kHz and the inductor is given as 0.44uH, then COUT should be larger than 197 μF, and also be smaller than 4.9 mF based on the design requirements. The characteristics of the capacitors should be also taken into considerations. For MLCC, use X5R or better dielectric and take into account derating of the capacitance by both DC bias and AC bias. When derating by DC bias and AC bias are 80% and 50%, respectively, the effective derating is 40% because 0.8 x 0.5 = 0.4. The capacitance of specialty polymer capacitors may change depending on the operating frequency. Consult capacitor manufacturers for specific characteristics. 7.5 Programming 7.5.1 PMBus General Descriptions The TPS53819A has seven internal custom user-accessible 8-bit registers. The PMBus interface has been designed for program flexibility, supporting a direct format for write operation. Read operations are supported for both combined format and stop separated format. While there is no auto increment or decrement capability in the TPS53819A PMBus logic, a tight software loop can be designed to randomly access the next register, regardless of which register was accessed first. The START and STOP commands frame the data packet and the REPEAT START condition is allowed when necessary. The device can operate in either standard mode (100 kb/s) or fast mode (400 kb/s). 7.5.2 PMBus Slave Address Selection The seven-bit slave address is 001A3A2A1A0x, where A3A2A1A0 is set by the ADDR pin on the device. Bit 0 is the data direction bit, i.e., 001A3A2A1A00 is used for write operation and 001A3A2A1A01 is used for read operation. 7.5.3 PMBus Address Selection The TPS53819A allows up to 16 different chip addresses for PMBus communication, with the first three bits fixed as 001. The address selection process is defined by the resistor divider ratio from VREG pin to ADDR pin, and the address detection circuit starts to work only after VDD input supply has risen above its UVLO threshold. The table below lists the divider ratio and some example resistor values. The 1% tolerance resistors with typical temperature coefficient of ±100ppm/°C are recommended. Higher performance resistors can be used if tighter noise margin is required for more reliable address detection, as shown in Table 2. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 21 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com Table 2. PMBus Address Selection Settings PMBus ADDRESS RESISTOR DIVIDER RATIO DIVIDER RATIO RANGE LOW HIGH HIGH-SIDE RESISTANCE (kΩ) LOW-SIDE RESISTANCE (kΩ) 0011111 > 0.557 — 1 300 0011110 0.509 0.4958 0.5247 160 165 0011101 0.461 0.4482 0.4772 180 154 0011100 0.416 0.4073 0.4294 200 143 0011011 0.375 0.3662 0.3886 200 120 0011010 0.334 0.3249 0.3476 220 110 0011001 0.297 0.2905 0.3067 249 105 0011000 0.263 0.2560 0.2725 249 88.7 0010111 0.229 0.2215 0.2385 240 71.5 0010110 0.195 0.1870 0.2044 249 60.4 0010101 0.160 0.1524 0.1703 249 47.5 0010100 0.126 0.1179 0.1363 249 36.0 0010011 0.096 0.0900 0.1024 255 27.0 0010010 0.068 0.0622 0.0752 255 18.7 0010001 0.041 0.0340 0.0480 270 11.5 0010000 < 0.013 300 1 — 7.5.4 Supported Formats The supported formats are described in this section. 7.5.4.1 Direct Format: Write The simplest format for a PMBus write is direct format. After the start condition [S], the slave chip address is sent, followed by an eighth bit indicating a write. The TPS53819A then acknowledges that it is being addressed, and the master responds with an 8-bit register address byte. The slave acknowledges and the master sends the appropriate 8-bit data byte. Again the slave acknowledges and the master terminates the transfer with the stop condition [P]. 7.5.4.2 Combined Format: Read After the start condition [S], the slave chip address is sent, followed by an eighth bit indicating a write. The TPS53819A then acknowledges that it is being addressed, and the master responds with an 8-bit register address byte. The slave acknowledges and the master sends the repeated start condition [Sr]. Again the slave chip address is sent, followed by an eighth bit indicating a read. The slave responds with an acknowledge followed by previously addressed 8 bit data byte. The master then sends a non-acknowledge (NACK) and finally terminates the transfer with the stop condition [P]. 7.5.4.3 Stop-Separated Reads Stop-separated read features are also available. This format allows a master to initialize the register address pointer for a read and return to that slave at a later time to read the data. In this format the slave chip address followed by a write bit are sent after a start [S] condition. The TPS53819A then acknowledges it is being addressed, and the master responds with the 8-bit register address byte. The master then sends a stop or restart condition and may then address another slave. After performing other tasks, the master can send a start or restart condition to the device with a read command. The device acknowledges this request and returns the data from the register location that had been set up previously. 7.5.5 Supported PMBus Commands The TPS53819A supports the PMBus commands shown in Table 1 only. Not all features of each PMBus command are supported. The CLEAR_FAULTS, STORE_DEFAULT_ALL and RESTORE_DEFAULT_ALL commands have no data bytes. The non-volatile memory (NVM) cells inside the TPS53819A can permanently store some registers. 22 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Table 3. Supported PMBus Commands COMMAND NOTES OPERATION Turn on or turn off switching converter only ON_OFF_CONFIG ON/OFF configuration CLEAR_FAULTS Clear all latched status flags WRITE_PROTECT Control writing to the PMBus device STORE_DEFAULT_ALL Store contents of user-accessible registers to non-volatile memory cells RESTORE_DEFAULT_ALL Copy contents of non-volatile memory cells to user-accessible registers STATUS_WORD PMBus read-only status and flag bits CUSTOM_REG MFR_SPECIFIC_00 (Custom Register 0): Custom register DELAY_CONTROL MFR_SPECIFIC_01 (Custom Register 1): Power on and power good delay times MODE_SOFT_START_CONFIG MFR_SPECIFIC_02 (Custom Register 2): Mode and soft-start time FREQUENCY_CONFIG MFR_SPECIFIC_03 (Custom Register 3): Switching frequency control VOUT_ADJUSTMENT MFR_SPECIFIC_04 (Custom Register 4): Output voltage adjustment control VOUT_MARGIN MFR_SPECIFIC_05 (Custom Register 5): Output voltage margin levels UVLO_THRESHOLD MFR_SPECIFIC_06 (Custom Register 6): Turn-on input voltage UVLO threshold 7.5.6 Unsupported PMBus Commands Do not send any unsupported commands to the TPS53819A. Even though the device receives an unsupported commands, it can acknowledge the unsupported commands and any related data bytes by properly sending the ACK bits. However, the device ignores the unsupported commands and any related data bytes, which means they do not affect the device operation in any way. Although the TPS53819A may acknowledge but ignore unsupported commands and data bytes, it can however, set the CML bit in the STATUS_BYTE register and then pull down the ALERT pin to notify the host. For this reason, unsupported commands and data bytes should not be sent to TPS53819A. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 23 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 7.6 Register Maps 7.6.1 OPERATION [01h] (R/W Byte) The TPS53819A supports only the functions of the OPERATION command shown in Table 4. Table 4. OPERATION Command Supported Functions COMMAND DEFINITION DESCRIPTION NVM OPERATION ON_OFF 0: turn off switching converter 1: turn on switching converter — OPERATION — not supported and don’t care — OPERATION OPMARGIN 00xx: turn off output voltage margin function 0101: turn on output voltage margin low and ignore fault 0110: turn on output voltage margin low and act on fault 1001: turn on output voltage margin high and ignore fault 1010: turn on output voltage margin high and act on fault — OPERATION — not supported and don’t care — OPERATION — not supported and don’t care — 7.6.2 ON_OFF_CONFIG [02h] (R/W Byte) The TPS53819A supports only the functions of the ON_OFF_CONFIG command shown in Table 5. Table 5. ON_OFF_CONFIG Command Supported Functions COMMAND DEFINITION DESCRIPTION NVM ON_OFF_CONFIG — not supported and don’t care — ON_OFF_CONFIG — not supported and don’t care — ON_OFF_CONFIG — not supported and don’t care — ON_OFF_CONFIG PU not supported and always set to 1 — ON_OFF_CONFIG CMD 0: ignore ON_OFF bit (OPERATION) (1) 1: act on ON_OFF bit (OPERATION) Yes ON_OFF_CONFIG CP 0: ignore EN pin 1: act on EN pin (1) Yes ON_OFF_CONFIG PL not supported and always set to 1 — ON_OFF_CONFIG SP not supported and always set to 1 — (1) TI default. Conditions required to enable the switcher: • If CMD is cleared and CP is set, then the switcher can be enabled only by the EN pin. • If CMD is set and CP is cleared, then the switcher can be enabled only by the ON_OFF bit (OPERATION) via PMBus. • If both CMD and CP are set, then the switcher can be enabled only when both the ON_OFF bit (OPERATION) and the EN pin are commanding to enable the device. • If both CMD and CP are cleared, then the switcher is automatically enabled after the ADDR detection sequence completes, regardless of EN pin and ON_OFF bit polarities. 24 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 7.6.3 WRITE_PROTECT [10h] (R/W Byte) The WRITE PROTECT command is used to control writing to the PMBus device. The intent of this command is to provide protection against accidental changes. This command has one data byte as described in Table 6. Table 6. WRITE_PROTECT Command Supported Functions COMMAND WRITE_PROTECT DEFINITION DESCRIPTION NVM 10000000: Disable all writes, except the WRITE_PROTECT command. — 01000000: Disable all writes, except the WRITE_PROTECT and OPERATION commands. — 00100000: Disable all writes, except the WRITE_PROTECT, OPERATION, and ON_OFF_CONFIG commands. — 00000000: Enable writes to all commands. — Others: Fault data — WP 7.6.4 CLEAR_FAULTS [03h] (Send Byte) The CLEAR_FAULTS command is used to clear any fault bits in the STATUS_WORD and STATUS_BYTE registers that have been set. This command clears all bits in all status registers. Simultaneously, the TPS53819A releases its ALERT signal output if the device is asserting the ALERT signal. If the fault condition is still present when the bit is cleared, the fault bits shall immediately be set again, and the ALERT signal should also be reasserted. The CLEAR_FAULTS does not cause a unit that has latched off for a fault condition to restart. Units that have been shut down for a fault condition can be restarted with one of the following conditions. • The output is commanded through the EN pin and/or ON_OFF bit based on the ON_OFF_CONFIG setting to turn off and then to turn back on. • VDD power is cycled for TPS53819A The CLEAR_FAULT command is used to clear the fault bits in the STATUS_WORD and STATUS_BYTE commands, and to release the ALERT pin. It is recommended not to send CLEAR_FAULT command when there is no fault to cause the ALERT pin to pull down. 7.6.5 STORE_DEFAULT_ALL [11h] (Send Byte) The STORE_DEFAULT_ALL command instructs TPS53819A to copy the entire contents of the operating memory to the corresponding locations in the NVM. The updated contents in the non-volitile memory (NVM)s become the new default values. The STORE_DEFAULT_ALL command can be used while the device is operating. However, the device may be unresponsive during the copy operation with unpredictable results. (see PMBus Power System Management Protocol Specificaiton, Part II - Command Language, Revision, 1.2, 6 Sept. 2010. www.powerSIG.org). It is recommended not to exceed 1000 write/erase cycles for non-volatile memory (NVM). 7.6.6 RESTORE_DEFAULT_ALL [12h] (Send Byte) The RESTORE_DEFAULT_ALL command instructs TPS53819A to copy the entire contents of the NVMs to the corresponding locations in the operating memory. The values in the operating memory are overwritten by the value retrieved from the NVM. It is permitted to use the RESTORE_DEFAULT_ALL command while the device is operating. However, the device may be unresponsive during the copy operation with unpredictable results. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 25 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 7.6.7 STATUS_WORD [79h] (Read Word) The TPS53819A does not support all functions of the STATUS_WORD command. A list of supported functions appears in Table 7. A status bit reflects the current state of the converter. Status bit becomes high when the specified condition has occurred and goes low when the specified condition has disappeared. A flag bit is a latched bit that becomes high when the specified condition has occurred and does not go back low when the specified condition has disappeared. STATUS_BYTE command is a subset of the STATUS_WORD command, or more specifically the lower byte of the STATUS_WORD. Table 7. STATUS_WORD Command Supported Functions COMMAND DEFINITION DESCRIPTION LOW BYTE: STATUS_BYTE [78h] Low STATUS_WORD BUSY not supported and always set to 0 Low STATUS_WORD OFF 0: raw status indicating device is providing power to output voltage 1: raw status indicating device is not providing power to output voltage Low STATUS_WORD VOUT_OV 0: latched flag indicating no output voltage overvoltage fault has occurred 1: latched flag indicating an output voltage overvoltage fault has occurred Low STATUS_WORD IOUT_OC 0: latched flag indicating no output current overcurrent fault has occurred 1: latched flag indicating an output current overcurrent fault has occurred Low STATUS_WORD VIN_UV 0: latched flag indicating input voltage is above the UVLO turn-on threshold 1: latched flag indicating input voltage is below the UVLO turn-on threshold Low STATUS_WORD TEMP 0: latched flag indicating no OT fault has occurred 1: latched flag indicating an OT fault has occurred Low STATUS_WORD CML 0: latched flag indicating no communication, memory or logic fault has occurred 1: latched flag indicating a communication, memory or logic fault has occurred Low STATUS_WORD OTHER not supported and always set to 0 High STATUS_WORD VOUT 0: latched flag indicating no output voltage fault or warning has occurred 1: latched flag indicating a output voltage fault or warning has occurred High STATUS_WORD IOUT 0: latched flag indicating no output current fault or warning has occurred 1: latched flag indicating an output current fault or warning has occurred High STATUS_WORD INPUT 0: latched flag indicating no input voltage fault or warning has occurred 1: latched flag indicating a input voltage fault or warning has occurred High STATUS_WORD MFR not supported and always set to 0 High STATUS_WORD PGOOD 0: raw status indicating PGOOD pin is at logic high 1: raw status indicating PGOOD pin is at logic low High STATUS_WORD FANS not supported and always set to 0 High STATUS_WORD OTHER not supported and always set to 0 High STATUS_WORD UNKNOWN not supported and always set to 0 HIGH BYTE The latched flags of faults can be removed or corrected only until one of the following conditions occurs: • The device receives a CLEAR_FAULTS command. • The output is commanded through the EN pin and/or ON_OFF bit based on the ON_OFF_CONFIG setting to turn off and then to turn back on • VDD power is cycled for TPS53819A If the fault condition remains present when the bit is cleared, the fault bits are immediately set again, and the ALERT signal is re-asserted. TPS53819A supports the ALERT pin to notify the host of fault conditions. Therefore, the best practice for monitoring the fault conditions from the host is to treat the ALERT pin as an interrupt source for triggering the corresponding interrupt service routine. It is recommended not to keep polling the STATUS_WORD or STATUS_BYTE registers from the host to reduce the firmware overhead of the host. 26 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 7.6.8 CUSTOM_REG (MFR_SPECIFIC_00) [D0h] (R/W Byte) Custom register 0 provides the flexibility for users to store any desired non-volatile information. For example, users can program this register to track versions of implementation or other soft identification information. The details of each setting are listed in Table 8. Table 8. CUSTOM_REG (MFR_SPECIFIC_00) Settings COMMAND DEFINITION DESCRIPTION NVM CUSTOM_REG — not supported and don’t care — CUSTOM_REG — not supported and don’t care — CUSTOM_REG (1) CUSTOMWORD 00000: (1) can be used to store any desired non-volatile information. Yes TI default 7.6.9 DELAY_CONTROL (MFR_SPECIFIC_01) [D1h] (R/W Byte) Custom register 1 provides software control over key timing parameters of the controller: Power-on delay (POD) time and power-good delay (PGD) time. The details of each setting are listed in Table 9. Table 9. DELAY_CONTROL (MFR_SPECIFIC_01) Settings COMMAND DEFINITION DESCRIPTION NVM DELAY_CONTROL — not supported and don’t care — DELAY_CONTROL — not supported and don’t care — DELAY_CONTROL DELAY_CONTROL (1) PGD 000: 001: 010: 011: 100: 101: 110: 111: 256 µs 512 µs 1.024 ms (1) 2.048 ms 4.096 ms 8.192 ms 16.384 ms 131.072 ms Yes POD 000: 001: 010: 011: 100: 101: 110: 111: 356 µs 612 µs 1.124 ms (1) 2.148 ms 4.196 ms 8.292 ms 16.484 ms 32.868 ms Yes TI default Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 27 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 7.6.10 MODE_SOFT_START_CONFIG (MFR_SPECIFIC_02) [D2h] (R/W Byte) Custom register 2 provides software control over mode selection and soft-start time (tSS). The details of each setting are listed in Table 10. Table 10. MODE_SOFT_START_CONFIG (MFR_SPECIFIC_02) Settings COMMAND DEFINITION DESCRIPTION NVM MODE_SOFT_START_CONFIG — not supported and don’t care — MODE_SOFT_START_CONFIG — not supported and don’t care — MODE_SOFT_START_CONFIG — not supported and don’t care — MODE_SOFT_START_CONFIG — not supported and don’t care — ms (1) ms ms ms MODE_SOFT_START_CONFIG SST 00: 1 01: 2 10: 4 11: 8 MODE_SOFT_START_CONFIG HICLOFF 0: hiccup after UV (1) Hiccup interval is (8.96 ms + soft-start time × 7) 1: latch-off after UV Yes MODE_SOFT_START_CONFIG CM 0: DCM (1) 1: FCCM Yes (1) Yes TI Default Figure 34 shows the soft-start timing diagram of TPS53819A with the programmable power-on delay time (tPOD), soft-start time (tSST), and PGOOD delay time (tPGD). During the soft-start time, the controller remains in discontinuous conduction mode (DCM), and then switches to forced continuous conduction mode (FCCM) at the end of soft-start if CM bit (MODE_SOFT_START_CONFIG) is set. EN Pin and/or ON_OFF bit tPOD tSST tPGD VOUT PGOOD DCM or FCCM (based on CM bit) DCM Time UDG-12070 Figure 34. Programmable Soft-Start Timing 28 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 7.6.11 FREQUENCY_CONFIG (MFR_SPECIFIC_03) [D3h] (R/W Byte) Custom register 3 provides software control over frequency setting (FS). The details of FS setting are listed in Table 11. Table 11. FREQUENCY_CONFIG (MFR_SPECIFIC_03) Settings COMMAND DEFINITION DESCRIPTION NVM FREQUENCY_CONFIG — not supported and don’t care — FREQUENCY_CONFIG — not supported and don’t care — FREQUENCY_CONFIG — not supported and don’t care — FREQUENCY_CONFIG — not supported and don’t care — FREQUENCY_CONFIG — not supported and don’t care — FREQUENCY_CONFIG (1) FS 000: 001: 010: 011: 100: 101: 110: 111: 275 kHz 325 kHz 425 kHz 525 kHz 625 kHz 750 kHz 850 kHz 1 MHz (1) Yes TI default. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 29 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 7.6.12 VOUT_ADJUSTMENT (MFR_SPECIFIC_04) [D4h] (R/W Byte) Custom register 4 provides ouput voltage adjustment (VOA) in ±0.75% steps, with a total range of ±9%. When fine adjustment is used together with the margin setting, the change in the output voltage is determined by the multiplication of the two settings. Table 12. VOUT_ADJUSTMENT (MFR_SPECIFIC_04) Settings COMMAND DEFINITION DESCRIPTION NVM VOUT_ADJUSTMENT — not supported and don’t care — VOUT_ADJUSTMENT — not supported and don’t care — VOUT_ADJUSTMENT — not supported and don’t care — VOUT_ADJUSTMENT (1) VOA 111xx: +9.00% 11011: +8.25% 11010: +7.50% 11001: +6.75% 11000: +6.00% 10111: +5.25% 10110: +4.50% 10101: +3.75% 10100: +3.00% 10011: +2.25% 10010: +1.50% 10001: +0.75% 10000: +0% (1) 01111: –0% 01110: –0.75% 01101: –1.50% 01100: –2.25% 01011: –3.00% 01010: –3.75% 01001: –4.50% 01000: –5.25% 00111: –6.00% 00110: –6.75% 00101: –7.50% 00100: –8.25% 000xx: –9.00% Yes TI default. 7.6.13 Output Voltage Fine Adjustment Soft Slew Rate To prevent sudden buildup of voltage across inductor, output voltage fine adjustment setting cannot change output voltage instantaneously. The internal reference voltage must slew slowly to its final target, and SST is used to provide further programmability. The details of output voltage fine adjustment slew rate are shown in Table 13. Table 13. Output Voltage Fine Adjustment Soft Slew Rate Settings COMMAND MODE_SOFT_START_CONF IG (1) 30 DEFINITION SST DESCRIPTION 00: 1 01: 1 10: 1 11: 1 step per step per step per step per 4 µs (1) 8 µs 16 µs 32 µs NVM Yes TI default. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 7.6.14 VOUT_MARGIN (MFR_SPECIFIC_05) [D5h] (R/W Byte) Custom register 5 provides output voltage margin high (VOMH) and output voltage margin low (VOML) settings. This register works in conjunction with PMBus OPERATION command to raise or lower the output voltage by a specified amount. This register settings described in Table 14 are also used together with the fine adjustment setting described in Table 12. For example, setting fine adjustment to +9% and margin to +12% changes the output by +22.08%, whereas setting fine adjustment to –9% and margin to –9% change the output by –17.19% Table 14. VOUT_MARGIN (MFR_SPECIFIC_05) Settings COMMAND VOUT_MARGIN VOUT_MARGIN (1) DEFINITION DESCRIPTION NVM VOMH 11xx: +12.0% 1011: +10.9% 1010: +9.9% 1001: +8.8% 1000: +7.7% 0111: +6.7% 0110: +5.7% 0101: +4.7% (1) 0100: +3.7% 0011: +2.8% 0010: +1.8% 0001: +0.9% 0000: +0% Yes VOML 0000: –0% 0001: –1.1% 0010: –2.1% 0011: –3.2% 0100: –4.2% 0101: –5.2% (1) 0110: –6.2% 0111: –7.1% 1000: –8.1% 1001: –9.0% 1010: –9.9% 1011: –10.7% 11xx: –11.6% Yes TI default. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 31 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 7.6.15 Output Voltage Margin Adjustment Soft-Slew Rate Similar to the output voltage fine adjustment, margin adjustment also cannot change output voltage instantaneously. The soft-slew rate of margin adjustment is also programmed by SST. The details are listed in Table 15. Table 15. Output Voltage Margin Adjustment Soft-Slew Rate Settings COMMAND DEFINITION MODE_SOFT_START_CONFIG (1) SST DESCRIPTION 00: 1 01: 1 10: 1 11: 1 step per step per step per step per 4 µs (1) 8 µs 16 µs 32 µs NVM Yes TI default. Figure 35 shows the timing diagram of the output voltage adjustment via PMBus. After receiving the write command of VOUT_ADJUSTMENT (MFR_SPECIFIC_04), the output voltage starts to be adjusted after tP delay time (about 50 μs). The time duration tDAC for each DAC step change can be controlled by SST bits (MODE_SOFT_START_CONFIG from 4 μs to 32 μs. PMBus Write VOA=10101b Write VOA=01010b tP tP VOUT tDAC UDG-12071 Figure 35. Output Voltage Adjustment via PMBus The margining function is enabled by setting the OPERATION command, and the margining level is determined by the VOUT_MARGIN (MFR_SPECIFIC_05) command. Figure 36 and Figure 37 illustrate the timing diagrams of the output voltage margining via PMBus. Figure 36 shows setting the margining level first, and then enabling margining by writing OPERATION command. After the OPERATION margin high command enables the margin high setting (VOMH), the output voltage starts to be adjusted after tP delay time (about 50 μs). The time duration tDAC for each DAC step change can be controlled by SST bits (MODE_SOFT_START_CONFIG) from 4 μs to 32 μs. PMBus Write VOMH=0100b Write OPMARGIN=1010b tP VOUT tDAC UDG-12072 Figure 36. Setting the Margining Level First 32 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Write VOMH=0001b Write OPMARGIN=1010b tP tP VOUT tDAC UDG-12073 Figure 37. Enabling Margining First As shown in Figure 37, the margining function is enabled first by a write command of OPERATION. The output voltage starts to be adjusted toward the default margin high level after tP delay. Since the margining function has been enabled, the output voltage can be adjusted again by sending a different margin high level with a write command of VOUT_MARGIN. The time duration tDAC for each DAC step change can be also controlled by SST bits (MODE_SOFT_START_CONFIG) from 4 μs to 32 μs. 7.6.16 UVLO_THRESHOLD (MFR_SPECIFIC_06) [D6h] Custom register 6 provides some limited programmability of input supply UVLO threshold, as described in Table 16. The default turn-on UVLO threshold is 4.25 V. Table 16. UVLO_THRESHOLD (MFR_SPECIFIC_06) Settings COMMAND DEFINITION DESCRIPTION NVM UVLO_THRESHOLD — not supported and don’t care — UVLO_THRESHOLD — not supported and don’t care — UVLO_THRESHOLD — not supported and don’t care — UVLO_THRESHOLD — not supported and don’t care — UVLO_THRESHOLD — not supported and don’t care — UVLO_THRESHOLD (1) VDDINUVLO 0xx: 10.2 V 100: not supported and should not be used 101: 4.25 V (1) 110: 6.0 V 111: 8.1 V Yes TI default. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 33 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 8 Application and Implementation NOTE Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality. 8.1 Application Information The TPS53819A device is a small-sized, single buck controller with adaptive on-time D-CAP2 mode control and PMBus. 8.2 Typical Application The following application shows a TPS53819A 12-V to 1.2-V point-of-load synchronous buck regulator. 34 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 TPS53819A Figure 38. Typical Application Schematic, TPS53819A Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 35 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 8.2.1 Design Requirements Table 17. Design Example Specifications PARAMETER VVIN Input voltage range VVIN(ripple) Input voltage ripple VOUT Output voltage VRIPPLE Output voltage ripple IOUT Output load current IOCL Output overcurrent fSW Switching frequency MIN TYP 8 12 MAX UNIT 14 V 240 mVPP 1.2 V 0 12 mVPP 20 A 25 A 425 kHz 8.2.2 Detailed Design Procedure Selecting external components is a simple process using D-CAP2™ Mode 8.2.2.1 Custom Design With WEBENCH® Tools Click here to create a custom design using the TPS53819A device with the WEBENCH® Power Designer. 1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements. 2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial. 3. Compare the generated design with other possible solutions from Texas Instruments. The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time pricing and component availability. In most cases, these actions are available: • Run electrical simulations to see important waveforms and circuit performance • Run thermal simulations to understand board thermal performance • Export customized schematic and layout into popular CAD formats • Print PDF reports for the design, and share the design with colleagues Get more information about WEBENCH tools at www.ti.com/WEBENCH. 8.2.2.2 Switching Frequency The switching frequency must first be decided on and is set using the PMBus. When deciding on a frequency a tradeoff between component size and efficiency must be made. A lower frequency reduces the switching losses in the MOSFETs improving efficiency but a larger inductance and/or output capacitance is required for low output voltage ripple. This example uses the TI default PMBus setting, 425 kHz. 8.2.2.3 Inductor (L1) Determined the inducatance to yield a ripple current (IIND(ripple)) of approximately ¼ to ½ of maximum output current. Larger ripple current increases output ripple voltage, improves the signal-to-noise ratio and helps stable operation. Maximum current ripple occurs with the maximum input voltage. Equation 9 calculates the recommended inductance. After choosing the inductance, use Equation 10 to calculate the ripple. L= 1 IIND(ripple ) ´ fSW IIND(ripple) = ´ )´ V (V IN(max ) - VOUT OUT VIN(max ) ( = 3 IOUT(max ) ´ fSW ´ (V IN(max ) - VOUT VIN(max) )´ V OUT (9) ) VIN(max) - VOUT ´ VOUT 1 ´ L ´ fSW VIN(max) (10) The inductor requires a low DCR to achieve good efficiency. The inductor also requires enough margin above the peak inductor current before saturation. The peak inductor current can be estimated in Equation 11. IIND(peak ) = IOCL + IIND(ripple ) (11) 36 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Using Equation 9 the recommended inductance for the example is 0.329 μH. An inductor supplied by Pulse Electronics (PA0513.441NLT) is selected with an inductance of 0.440 μH at 0 A and 0.363 μH at its 30 A rated current. The saturation current is 35 A and the DCR is 0.32 mΩ. Using Equation 10 with the selected inductance and maximum input voltage, the current ripple is estimated to be 6.23 A. Equation 11 calculates the peak current to be 31.3 A, well below the saturation current of the inductor. The output current threshold when the supply operates in DCM or CCM can also be estimated as half the estimated current ripple. With the maximum 14 V input in this design the output current threshold is 3.12 A. With lower input voltages, ripple decreases and so does the threshold. 8.2.2.4 Output Capacitors (C10, C11, C12, C13, C14) Determine the output capacitance to meet the load transient, ripple requirements, and to meet small-signal stability as shown in Equation 12. 5 ´ fC2 £ RC1 ´ CC1 ´ 0.6 ´ (0.67 + D ) f £ SW 2p ´ G ´ L ´ COUT ´ VOUT 3 where • • • G =0.25 RC1 × CC1 time constant can be referred to Table 1 D is the duty cycle (12) Based on Equation 12, the value of COUT to ensure small signal stability can be calculated using Equation 13 and Equation 14. These equations assume MLCC are used and the ESR effects are negligible. If a high ESR output capacitor is used, the effects may reduce the minimum and maximum capacitance. In the design example using Table 1 for 425-kHz switching frequency, the time constant is 62 μs. The recommended minimum capacitance for a design with an 8-V minimum input voltage is 260 μF. The recommended maximum capacitance for design with a 14-V maximum input voltage is 4842 μF. COUT COUT æ V RC1 ´ CC1 ´ 0.6 ´ ç 0.67 + OUT ç VIN(max) è £ 2p ´ G ´ L ´ 5 ´ fC2 ´ VOUT ö ÷ ÷ ø æ V RC1 ´ CC1 ´ 0.6 ´ ç 0.67 + OUT ç VIN(min) è ³ f 2p ´ G ´ L ´ SW ´ VOUT 3 ö ÷ ÷ ø (13) (14) Select a larger output capacitance to decrease the output voltage change that occurs during a load transient and the output voltage ripple. The minimum output capacitance to meet an output voltage ripple requirement can be calculated with Equation 15. In the example the minimum output capacitance for 12 mVPP ripple is 162 μF. If non ceramic capacitors are used Equation 16 calculates the maximum equivalent series resistance (ESR) of the output capacitor to meet the ripple requirement. Equation 17 calculates the required RMS current rating for the output capacitor. In this example with 12-V nominal input voltage it is 1.77 A. Finally the output capacitor must be rated for the output voltage. IIND(ripple) COUT ³ 8 ´ VRIPPLE ´ fSW (15) æ IIND(ripple) VRIPPLE - çç è 8 ´ COUT ´ fSW ESR £ IIND(ripple) ICOUT(RMS) = ö ÷÷ ø (16) IIND(ripple) 12 (17) Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 37 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com This example uses five 1210, 100-μF, 6.3-V, X5R ceramic capacitors with 2 mΩ of ESR. From the data sheet the estimated DC derating of 95% and AC derating of 70% for a total of 66.5% at room temperature. The total output capacitance is approximately 332.5 μF. 8.2.2.5 Input Capacitors (C1, C2, C3, C4, C5) Choose an input capacitance that reduces the input voltage ripple. Equation 18 calculates the minimum input capacitance. In the example design to limit the input ripple to 240 mV, assuming all ceramic and ignoring ESR ripple, the minimum input capacitance is 27.8 μF. The input capacitor must also be rated for the input RMS current calculated in Equation 19. For this design example this current is 8.95 A with the minimum 8-V input voltage. Also, the input capacitors must be rated for the maximum input voltage. DIL CIN ³ 8 ´ VINRIPPLE ´ fSW (18) ICIN(RMS) = I OUT ´ ( VIN(min) - VOUT VOUT ´ VIN(min) VIN(min) ) (19) This example uses four 1206, 22 μF, 16 V, X5R ceramic capacitors with 3 mΩ of ESR. An additional 0.1-μF capacitor is placed close to the drain of the high-side MOSFET and the source of the low-side MOSFET. 8.2.2.6 MOSFET (Q1, Q2) The TPS53819A uses two external N-channel MOSFETs. The VDS rating should be greater than the maximum input voltage and include some tolerance for ringing on the switching node. It must also be rated for the DC current. The high-side MOSFET conducts the input current and the low-side MOSFET conducts the output current. The gate drive voltage is set by the VREG voltage of 5 V typical. The gate capacitance should be reduced to minimize the current required to turn on the MOSFETs and switching losses. However it is recommended the low-side MOSFET have a higher gate capacitance to avoid unintentional shoot-through caused by the high dv/dt on the switching node during the high-side turn-on. A reduction in current also reduces power dissipation in TPS53819A. Choose a low RDS(on) to reduce conduction losses especially for the low-side MOSFET because it conducts the output current. This design uses the CSD87350Q5D, 30-V, 40-A, NexFET power block with integrated low-side and high-side MOSFETs. This is optimized for applications with a 5 V gate drive. The typical gate to source capacitance of the high-side and low-side MOSFETs is 1341 pF and 2900 pF respectively. Using Equation 1 and Equation 2 the average drive currents are 2.7 mA and 5.9 mA. With Equation 3 the power dissipated in the driver is estimated to 42.4 mW. The RDS(on) of the high-side and low-side MOSFETs with a 5 V gate drive voltage is 5 mΩ and 2.2 mΩ respectively. A small, 4.7-Ω resistance from R6, is added in series between DRVH and the gate of the high-side MOSFET. This slows down the turn-on time of the high-side MOSFET dv/dt and reduces rising edge ringing on the switching node to help prevent shoot-through. This value should be kept small and if it is too large it may lead to too large of a delay time in the turn-on time of the high-side switch. 8.2.2.7 VREG Bypass Capacitor (C18) A ceramic capacitor with a recommended value between 0.47-μF and 2.2-μF is required on the VREG pin for proper operation. The example uses a 1-μF capacitor. Choose one rated for the VREG 5.5-V maximum voltage in order to supply the instantaneous drive current of the low-side MOSFET. 8.2.2.8 VDD Bypass Capacitor (C19) A 1-μF capacitor should be placed at the VDD pin rated for the maximum input voltage. If power stage switching noise is causing faults, a small resistor (R12) can be added between VDD and all the input capacitors (C1-C5). This creates an R-C filter and reduces any switching noise in the device input. 38 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 8.2.2.9 VBST Capacitor (C7) The bootstrap capacitor is required to generate the high-side gate drive bias voltage and provide the instantaneous drive current for DRVH. A 0.1-μF ceramic capacitor is recommended to limit the ripple voltage. R5 (0-Ω) resistance, is added in series with the bootstrap capacitor. This resistor can be used to slow down the turn-on time of the high-side MOSFET dv/dt and reduces rising edge ringing on the SW node to help prevent shoot-through. Keep the value small because a higher value may increase the the turn-on delay time of the highside switch. 8.2.2.10 Snubber (C8 and R9) Fast-switching edges and parasitic inductance and capacitance cause voltage ringing on the SW node . If the ringing results in excessive voltage on the SW node or erratic operation an R-C snubber can be used to reduce ringing on the SW node and ensure proper operation in all operating conditions. 8.2.2.11 Feedback Resistance, RFBH and RFBL (R17 and R18) The values of the voltage-divider resistors, RFBH and RFBL determine the output voltage as shown in Figure 38. RFBH is connected between the FB pin and the output, and RFBL is connected between the FB pin and GND. The recommended RFBH value is between 10 kΩ and 20 kΩ. Determine RFBL using Equation 20. RFBH RFBL = é æ öö ù 1 æ 1 ê VOUT - ´ ç IIND(ripple) ´ ç ESR + ÷ ÷÷ ú ç 2 è 8 ´ COUT ´ fSW ø ø ú ê è ê ú -1 ö ú ö L ê 0.6 - çæ 1 ´ æ I ç IND(ripple) ´ ÷ - VOFS ÷÷ ú ê ç 4 ´ RC1 ´ CC1 ø è2 è ø û ë where • • VOFS is the internal offset voltage (4 mV) ESR is the from the output capacitors (20) In this example R17 has a value of 10-kΩ. R18 is calculated to be 9.91 kΩ. The nearest standard value of 10 kΩ is used for R18. 8.2.2.12 Overcurrent Limit (OCL) Setting Resistance (R10) Combining Equation 7 and Equation 8, Equation 21 calculates RTRIP. RTRIP æ ö æ (V - VOUT ) ö VOUT ÷ ´ RDS(on) 8 ´ ç IOCL - ç IN ´ ÷ ç (2 ´ L X ) ÷ (fSW ´ VIN ) ÷ ç è ø è ø = ITRIP (21) In this example for a 25-A current limit, RTRIP is calculated as 38.5 kΩ and is rounded up to the nearest standard value of 39.2 kΩ. 8.2.2.13 PMBus Device Address (R3 and R4) The PMBus address is selected using a resistive divider as shown in Table 2. In this example the address is set to 0010000 with a 300-kΩ resistor (R3) and a 1.00-kΩ (R4). 8.2.2.14 PGOOD Pullup Resistor (R2) A pullup resistor is required because the PGOOD pin is an open-drain output. Use a value between 10 kΩ to 100 kΩ. The recommended max 100 kΩ resistor is used. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 39 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 8.2.2.15 SCL and SDA Pulldown Resistors (R14 and R15) If there is no PMBus (I2C) needed in the system, pull these two pins down to ground. If a PMBus interface is always present, then these resistors are not needed. This example design uses 100-kΩ of resistance to pull these pins down to ground, allowing it to operate with or without a PMBus interface. 8.2.2.16 PMBus Pullup Resistors Due to the limited drive strength of pulldown MOSFETs on SDA and ALERT pins, the external PMBus pullup resistors must be kept within certain ranges. For example, if the external PMBus supply is 3.3 V, then use a pullup resistance of 1-kΩ. If the external PMBus supply is 5 V, then use a pullup resistance of 1.5 kΩ. 8.2.3 Application Curves 100 90 VIN AC Efficiency (%) 80 70 SW 60 50 40 30 VOUT AC 20 DCM 10 0 0.001 0.01 0.1 1 Output Current (A) VIN (V) FCCM 8 12 14 10 100 VIN = 12 V fSW = 425 kHz IOUT = 25 A Figure 40. Output Ripple Figure 39. Efficiency 9 Power Supply Recommendations The TPS53819A device operates using an input voltage supply range between 3 V and 28 V (4.5-V to 28-V biased). This input supply must be well regulated. Proper bypassing of input supplies and internal regulators is also critical for noise performance, as is PCB layout and grounding scheme. 40 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 10 Layout 10.1 Layout Guidelines Note these design considerations before starting a layout work using TPS53819A • Inductor, VIN capacitors, VOUT capacitors and MOSFETs are the power components and should be placed on one side of the PCB (solder side). Other small signal components can be placed on another side (component side). At least one inner plane should be inserted, connected to ground, in order to shield and isolate the small signal traces from noisy power lines. • Place all sensitive analog traces and components such as FB, VO, TRIP, PGOOD, and EN away from highvoltage switching nodes such as SW, DRVL, DRVH or VBST to avoid coupling. Use internal layers as ground planes and shield feedback trace from power traces and components. • Keep PMBus interfacing signals away from the sensitive analog traces. • The DC/DC converter has several high-current loops. Minimize the area of these loops in order to suppress switching noise. – The path from the VIN capacitors through the high and low-side MOSFETs and back to the capacitors through ground, is the most important loop area to minimize. Connect the negative node of the VIN capacitors and the source of the low-side MOSFET at ground as close as possible. – The second important loop is the path from the low-side MOSFET through inductor and VOUT capacitors, and back to source of the low-side MOSFET through ground. Connect source of the low-side MOSFET and negative node of VOUT capacitors at ground as close as possible. – The third important loop is that of the gate driving system for the low-side MOSFET. To turn on the lowside MOSFET, high current flows from the VDRV capacitor through the gate driver and the low-side MOSFET, and back to negative node of the capacitor through ground. To turn off the low-side MOSFET, high current flows from gate of the low-side MOSFET through the gate driver and PGND of the device, and back to source of the low-side MOSFET through ground. Connect the negative node of the VREG capacitor, source of the low-side MOSFET and PGND of the device at ground as close as possible. • A separate AGND from the high-current loop PGND should be used for the return of the sensitive analog circuitry. The two grounds should connect at a single point as close to the GND pin as possible. • Minimize the current loop from the VDD and VREG pins through their respective capacitors to the GND pin. • Because the TPS53819A controls the output voltage referring to voltage across VOUT capacitor, the top-side resistor of the voltage divider should be connected to the positive node of the VOUT capacitor. In a same manner both bottom side resistor and GND of the device should be connected to the negative node of VOUT capacitor. The trace from these resistors to the VFB pin should be short and thin. Place on the component side and avoid vias between these resistors and the device. • Connect the overcurrent setting resistor from the TRIP pin to ground and make the connections as close as possible to the device. Avoid coupling a high-voltage switching node to the trace from the TRIP pin to RTRIP and from RTRIP to ground . • Connections from gate drivers to the respective gate of the high-side or the low-side MOSFET should be as short as possible to reduce stray inductance. Use 0.65 mm (25 mils) or wider trace and vias of at least 0.5 mm (20 mils) diameter along this trace. • The PCB trace defined as switch node, which connects to source of high-side MOSFET, drain of low-side MOSFET and high-voltage side of the inductor, should be as short and wide as possible. • Follow any layout considerations for the MOSFET provided by the MOSFET manufacturer. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 41 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 10.2 Layout Example VIN VOUT HF capacitor LOUT CIN COUT SW GND Figure 41. Top Layer 42 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 Layout Example (continued) Bottom layer PMBus VIN VOUT U 1 CIN COUT GND Figure 42. Bottom Layer Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 43 TPS53819A SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 www.ti.com 11 Device and Documentation Support 11.1 Device Support 11.1.1 Development Support 11.1.1.1 Custom Design With WEBENCH® Tools Click here to create a custom design using the TPS53819A device with the WEBENCH® Power Designer. 1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements. 2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial. 3. Compare the generated design with other possible solutions from Texas Instruments. The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time pricing and component availability. In most cases, these actions are available: • Run electrical simulations to see important waveforms and circuit performance • Run thermal simulations to understand board thermal performance • Export customized schematic and layout into popular CAD formats • Print PDF reports for the design, and share the design with colleagues Get more information about WEBENCH tools at www.ti.com/WEBENCH. 11.2 Receiving Notification of Documentation Updates To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper right corner, click on Alert me to register and receive a weekly digest of any product information that has changed. For change details, review the revision history included in any revised document. 11.3 Community Resources The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of Use. TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help solve problems with fellow engineers. Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and contact information for technical support. 11.4 Trademarks D-CAP2, Eco-mode, E2E are trademarks of Texas Instruments. WEBENCH is a registered trademark of Texas Instruments. PMBus is a trademark of SMIF, Inc. All other trademarks are the property of their respective owners. 11.5 Electrostatic Discharge Caution These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. 11.6 Glossary SLYZ022 — TI Glossary. This glossary lists and explains terms, acronyms, and definitions. 44 Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A TPS53819A www.ti.com SLUSB56B – NOVEMBER 2012 – REVISED APRIL 2019 12 Mechanical, Packaging, and Orderable Information The following pages include mechanical, packaging, and orderable information. This information is the most current data available for the designated devices. This data is subject to change without notice and revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation. Submit Documentation Feedback Copyright © 2012–2019, Texas Instruments Incorporated Product Folder Links: TPS53819A 45 PACKAGE OPTION ADDENDUM www.ti.com 10-Dec-2020 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) Device Marking (3) (4/5) (6) TPS53819ARGTR ACTIVE VQFN RGT 16 3000 RoHS & Green NIPDAU Level-2-260C-1 YEAR -40 to 85 3819A TPS53819ARGTT ACTIVE VQFN RGT 16 250 RoHS & Green NIPDAU Level-2-260C-1 YEAR -40 to 85 3819A (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
TPS53819ARGTT 价格&库存

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TPS53819ARGTT
    •  国内价格
    • 1000+11.66000

    库存:2545

    TPS53819ARGTT
    •  国内价格 香港价格
    • 1+26.739281+3.23597
    • 10+24.0114210+2.90584
    • 25+22.6970625+2.74678
    • 100+19.67090100+2.38056

    库存:1000