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TPS40304DRCR

TPS40304DRCR

  • 厂商:

    BURR-BROWN(德州仪器)

  • 封装:

    VSON-10_3X3MM-EP

  • 描述:

    IC REG CTRLR BUCK 10SON

  • 数据手册
  • 价格&库存
TPS40304DRCR 数据手册
Product Folder Order Now Support & Community Tools & Software Technical Documents Reference Design TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 TPS4030x 3-V to 20-V Input, Voltage Mode, Synchronous Buck Controller 1 Features 3 Description • • The TPS4030x is a family of cost-optimized synchronous buck controllers that operate from 3-V to 20-V input. The controller implements a voltage-mode control architecture with input-voltage feed-forward compensation that responds instantly to a change in input voltage. The switching frequency is fixed at 300 kHz, 600 kHz, or 1.2 MHz. 1 • • • • • • • • • • Input Voltage Range From 3 V to 20 V 300-kHz (TPS40303), 600-kHz (TPS40304), and 1.2-MHz (TPS40305) Switching Frequencies High- and Low-Side FET RDS(on) Current Sensing Programmable Thermally Compensated OCP Levels Programmable Soft Start 600-mV, 1% Reference Voltage Voltage Feed-Forward Compensation Supports Prebiased Output Frequency Spread Spectrum Thermal Shutdown Protection at 145°C 10-Pin 3-mm × 3-mm VSON Package With Ground Connection to Thermal Pad Create a Custom Design Using the TPS4030x With the WEBENCH® Power Designer The frequency spread-spectrum (FSS) feature adds to the switching frequency, significantly reducing the peak EMI noise and making it much easier to comply with EMI standards. The TPS4030x offers design with a variety of userprogrammable functions, including soft start, overcurrent protection (OCP) levels, and loop compensation. OCP level may be programmed by a single external resistor connected from the LDRV pin to circuit ground. During initial power on, the TPS4030x enters a calibration cycle, measures the voltage at the LDRV pin, and sets an internal OCP voltage level. During operation, the programmed OCP voltage level is compared to the voltage drop across the low-side FET when it is on to determine whether there is an overcurrent condition. The TPS4030x then enters a shutdown and restart cycle until the fault is removed. 2 Applications • • • • • POL Modules Printers Digital TVs Telecom USB Type-C Wall Receptacles Device Information(1) PART NUMBER PACKAGE BODY SIZE (NOM) TPS40303 TPS40304 VSON (10) 3.00 mm × 3.00 mm TPS40305 (1) For all available packages, see the orderable addendum at the end of the data sheet. Simplified Application Diagram VOUT VIN TPS4030x 5 FB BOOT 6 4 COMP HDRV 7 3 PGOOD SW 8 2 EN/SS LDRV/OC 9 1 VDD VOUT SD VIN GND BP 10 PAD Copyright © 2017, Texas Instruments Incorporated 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. TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com Table of Contents 1 2 3 4 5 6 7 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Pin Configuration and Functions ......................... Specifications......................................................... 1 1 1 2 3 4 6.1 6.2 6.3 6.4 6.5 6.6 4 4 4 4 5 7 Detailed Description .............................................. 9 7.1 7.2 7.3 7.4 8 Absolute Maximum Ratings ...................................... ESD Ratings.............................................................. Recommended Operating Conditions....................... Thermal Information .................................................. Electrical Characteristics........................................... Typical Characteristics .............................................. Overview ................................................................... 9 Functional Block Diagram ......................................... 9 Feature Description................................................... 9 Device Functional Modes........................................ 13 Application and Implementation ........................ 14 8.1 Application Information............................................ 14 8.2 Typical Applications ................................................ 14 9 Power Supply Recommendations...................... 29 10 Layout................................................................... 30 10.1 Layout Guidelines ................................................. 30 10.2 Layout Example .................................................... 31 11 Device and Documentation Support ................. 32 11.1 11.2 11.3 11.4 11.5 11.6 11.7 11.8 11.9 Device Support...................................................... Custom Design With WEBENCH® Tools ............. Documentation Support ........................................ Related Links ........................................................ Receiving Notification of Documentation Updates Community Resources.......................................... Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 32 32 32 32 32 33 33 33 33 12 Mechanical, Packaging, and Orderable Information ........................................................... 33 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision C (January 2018) to Revision D Page • Changed title of data sheet for SEO ..................................................................................................................................... 1 • Added "USB Type-C Wall Receptacles" to Applications; added links for WEBENCH ........................................................... 1 • Deleted redundant Dissipation Ratings table ........................................................................................................................ 4 Changes from Revision B (May 2015) to Revision C Page • Added top nav icon for TPS40303 TI Design ........................................................................................................................ 1 • Deleted Related Devices table from Device and Documentation Support .......................................................................... 32 Changes from Revision A (August 2012) to Revision B • Page Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section .............................. 1 Changes from Original (November 2009) to Revision A • 2 Page Changed minimum controllable pulse width max value from 100 to 70 ................................................................................. 5 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 5 Pin Configuration and Functions DRC Package 10-Pins VSON Top View FB COMP PGOOD EN/SS VDD 5 4 3 2 1 8 9 10 SW LDRV/ OC BP Thermal Pad 6 7 BOOT HDRV Pin Functions PIN I/O DESCRIPTION NAME NO. BOOT 6 I Gate drive voltage for the high-side N-channel MOSFET. A 0.1-µF capacitor (typical) must be connected between this pin and SW. For low input voltage operation, an external schottky diode from BP to BOOT is recommended to maximize the gate drive voltage for the high-side. BP 10 O Output bypass for the internal regulator. Connect a low ESR bypass ceramic capacitor of 1 µF or greater from this pin to GND. COMP 4 O Output of the error amplifier and connection node for loop feedback components. EN/SS 2 I Logic level input which starts or stops the controller via an external user command. Letting this pin float turns the controller on. Pulling this pin low disables the controller. This is also the soft-start programming pin. A capacitor connected from this pin to GND programs the soft-start time. The capacitor is charged with an internal current source of 10 µA. The resulting voltage ramp of this pin is also used as a second non-inverting input to the error amplifier after a 0.8 V (typical) level shift downwards. Output regulation is controlled by the internal level shifted voltage ramp until that voltage reaches the internal reference voltage of 600 mV – the voltage ramp of this pin reaches 1.4 V (typical). Optionally, a 267-kΩ resistor from this pin to BP enables the FSS feature. FB 5 I Inverting input to the error amplifier. In normal operation, the voltage on this pin is equal to the internal reference voltage. HDRV 7 O Bootstrapped gate drive output for the high-side N-channel MOSFET. LDRV/OC 9 O Gate drive output for the low-side synchronous rectifier N-channel MOSFET. A resistor from this pin to GND is also used to determine the voltage level for OCP. An internal current source of 10 µA flows through the resistor during initial calibration and that sets up the voltage trip point used for OCP. PGOOD 3 O Open-drain power good output. SW 8 O Sense line for the adaptive anti-cross conduction circuitry. Serves as common connection for the flying highside FET driver. VDD 1 I Power input to the controller. Bypass VDD to GND with a low ESR ceramic capacitor of at least 1-µF close to the device. GND Thermal Pad — Ground connection to the controller. This is also the thermal pad used to conduct heat from the device. This connection serves a twofold purpose. The first is to provide an electrical ground connection for the device. The second is to provide a low thermal impedance path from the device die to the PCB. This pad should be tied externally to a ground plane. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 3 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 6 Specifications 6.1 Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted) (1) MIN MAX UNIT VDD –0.3 22 V SW –3 27 V –5 V –0.3 30 V SW (< 100-ns pulse width, 10 µJ) BOOT HDRV –5 30 V BOOT-SW, HDRV-SW (differential from BOOT or HDRV to SW) –0.3 7 V COMP, PGOOD, FB, BP, LDRV, EN/SS –0.3 7 V Operating junction temperature, TJ –40 145 °C Storage temperature, Tstg –55 150 °C (1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other condition beyond those included under Recommended Operating Conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods of time may affect device reliability. 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) ±1500 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 MIN VDD Input voltage TJ Operating junction temperature NOM MAX UNIT 3 20 V –40 125 °C 6.4 Thermal Information TPS4030x THERMAL METRIC (1) DRC (VSON) UNIT 10 PINS RθJA Junction-to-ambient thermal resistance 44.3 °C/W RθJC(top) Junction-to-case (top) thermal resistance 56.1 °C/W RθJB Junction-to-board thermal resistance 19.2 °C/W ψJT Junction-to-top characterization parameter 0.7 °C/W ψJB Junction-to-board characterization parameter 19.4 °C/W RθJC(bot) Junction-to-case (bottom) thermal resistance 5.5 °C/W (1) 4 For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report. Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 6.5 Electrical Characteristics TJ = –40°C to 125°C, VVDD = 12 V, all parameters at zero power dissipation (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX TJ = 25°C, 3 V < VVDD < 20 V 597 600 603 –40°C < TJ < 125°C, 3 V < VVDD < 20 V 594 600 606 UNIT VOLTAGE REFERENCE VFB FB input voltage mV INPUT SUPPLY VVDD Input supply voltage range 20 V IDDSD Shutdown supply current VEN/SS < 0.2 V 3 70 100 µA IDDQ Quiescent, nonswitching Let EN/SS float, VFB = 1 V 2.5 3.5 mA ENABLE/SOFT START VIH High-level input voltage, EN/SS 0.55 0.7 1 V VIL Low-level input voltage, EN/SS 0.27 0.3 0.33 V ISS Soft-start source current VSS Soft-start voltage level 8 10 12 µA 0.4 0.8 1.3 V 6.2 6.5 6.8 V 70 110 mV 270 300 330 kHz 540 600 660 kHz 1.02 1.20 1.38 MHz VVDD/6.6 VVDD/6 VVDD/5.4 BP REGULATOR VBP Output voltage IBP = 10 mA VDO Regulator dropout voltage, VVDD – VBP IBP = 25 mA, VVDD = 3 V OSCILLATOR TPS40303 fSW PWM frequency TPS40304 3 V < VVDD < 20 V TPS40305 VRAMP (1) Ramp amplitude fSWFSS Frequency spread-spectrum frequency deviation fMOD Modulation frequency 12% V fSW 25 kHz PWM TPS40303 DMAX (1) Maximum duty cycle TPS40304 90% VFB = 0 V, 3 V < VVDD < 20 V TPS40305 tON(min) (1) tDEAD 90% 85% Minimum controllable pulse width 70 HDRV off to LDRV on 5 25 35 LDRV off to HDRV on 5 25 30 Gain bandwidth product 10 24 Open loop gain 60 Output driver dead time ns ns ERROR AMPLIFIER GBWP AOL (1) (1) IIB Input bias current (current out of FB pin) VFB = 0.6 V IEAOP Output source current VFB = 0 V 2 IEAOM Output sink current VFB = 1 V 2 MHz dB 75 nA mA PGOOD VOV Feedback upper voltage limit for PGOOD 655 675 700 VUV Feedback lower voltage limit for PGOOD 500 525 550 VPGD-HYST PGOOD hysteresis voltage at FB 25 40 RPGD PGOOD pulldown resistance VFB = 0 V, IFB = 5 mA 30 70 Ω IPGDLK PGOOD leakage current 550 mV < VFB < 655 mV, VPGOOD = 5 V 10 20 µA (1) mV Ensured by design. Not production tested. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 5 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com Electrical Characteristics (continued) TJ = –40°C to 125°C, VVDD = 12 V, all parameters at zero power dissipation (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT OUTPUT DRIVERS RHDHI High-side driver pullup resistance VBOOT – VSW = 5 V, IHDRV = –100 mA 0.8 1.5 2.5 Ω RHDLO High-side driver pulldown resistance VBOOT – VSW = 5 V, IHDRV = 100 mA 0.5 1 2.2 Ω RLDHI Low-side driver pullup resistance ILDRV = –100 mA 0.8 1.5 2.5 Ω RLDLO Low-side driver pulldown resistance ILDRV = 100 mA 0.35 0.6 1.2 (1) High-side driver rise time CLOAD = 5 nF tHFALL (1) tLRISE (1) tLFALL (1) tHRISE Ω 15 ns High-side driver fall time 12 ns Low-side driver rise time 15 ns Low-side driver fall time 10 ns Minimum pulse time during short circuit 250 ns Switch leading-edge blanking pulse time 150 ns OVERCURRENT PROTECTION tPSSC(min) (1) tBLNKH (1) VOCH OC threshold for high-side FET TJ = 25°C 360 450 580 IOCSET OCSET current source TJ = 25°C 9.5 10 10.5 mV µA VLD-CLAMP Maximum clamp voltage at LDRV 260 340 400 mV VOCLOS OC comparator offset voltage for lowTJ = 25°C side FET –8 8 mV VOCLPRO (1) Programmable OC range for low-side TJ = 25°C FET 12 300 mV VTHTC (1) OC threshold temperature coefficient (both high-side and low-side) tOFF OC retry cycles on EN/SS pin 3000 ppm 4 Cycle BOOT DIODE VDFWD Bootstrap diode forward voltage IBOOT = 5 mA 0.8 V 145 °C 20 °C THERMAL SHUTDOWN TJSD (1) TJSDH 6 Junction shutdown temperature (1) Hysteresis Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 6.6 Typical Characteristics 314 625 620 VVDD = 3V 312 311 310 309 VVDD = 12 V 308 307 VVDD = 20 V fSW – Switching Frequency – kHz fSW – Switching Frequency – kHz 313 306 VVDD = 20 V 615 610 605 VVDD = 12 V 600 VVDD = 3V 595 590 585 TPS40303 305 –40 –25 –10 5 20 35 50 65 80 TPS40304 580 –40 –25 –10 95 110 125 5 20 35 50 65 80 95 110 125 TJ – Junction Temperature – °C TJ – Junction Temperature – °C Figure 1. Switching Frequency vs Junction Temperature Figure 2. Switching Frequency vs Junction Temperature 2.24 1.4 VVDD = 20 V 2.22 1.3 1.25 1.2 VVDD = 3V VVDD = 12 V 1.15 1.1 IDDQ – Quiescent Current – mA fSW – Switching Frequency – MHz 1.35 2.20 2.18 2.16 2.14 1.05 TPS40305 1 –40 –25 –10 5 20 35 50 65 80 2.12 –40 –25 –10 95 110 125 VVDD = 12 V 5 20 35 50 65 80 95 110 125 TJ – Junction Temperature – °C Figure 4. Quiescent Current vs Junction Temperature 72 14 70 13 IOCSET – OCSET Current Source– mA IDD(SD)– Shutdown Current – mA TJ – Junction Temperature – °C Figure 3. Switching Frequency vs Junction Temperature 68 66 64 62 60 12 11 10 9 8 7 58 –40 –25 –10 VVDD = 12 V 5 20 35 50 65 80 95 110 125 6 –40 –25 –10 5 20 35 50 65 80 95 110 125 TJ – Junction Temperature – °C TJ – Junction Temperature – °C Figure 5. Shutdown Current vs Junction Temperature Figure 6. OCSET Current Source vs Junction Temperature Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 7 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com Typical Characteristics (continued) 740 VIH – Enable High-Level Threshold Voltage – mV VFB – Feedback Reference Voltage – mV 600.8 600.6 600.4 600.2 600 599.8 599.6 599.4 –40 –25 –10 5 20 35 50 65 80 720 700 680 660 640 620 –40 –25 –10 95 110 125 TJ – Junction Temperature – °C Figure 7. Feedback Reference Voltage vs Junction Temperature 20 35 50 65 80 95 110 125 Figure 8. Enable High-Level Threshold Voltage vs Junction Temperature 303.0 VIL – Enable Low-Level Threshold Voltage – mV VOCH – High-Side Overcurrent Threshold – mV 600 302.5 302.0 301.5 301.0 300.5 300.0 –40 –25 –10 5 20 35 50 65 80 550 500 450 400 350 –40 –25 –10 95 110 125 5 20 35 50 65 80 95 110 125 TJ – Junction Temperature – °C TJ – Junction Temperature – °C Figure 9. Enable Low-Level Threshold Voltage vs Junction Temperature Figure 10. High-Side Overcurrent Threshold vs Junction Temperature 1000 750 975 Overvoltage VSS – Soft-Start Voltage – mV VOV/VUV – Power Good Threshold Voltage – mV 800 700 650 600 550 500 950 925 900 875 850 825 800 Undervoltage 450 400 –40 –25 –10 8 5 TJ – Junction Temperature – °C 5 20 35 50 65 775 80 95 110 125 750 –40 –25 –10 5 20 35 50 65 80 95 110 125 TJ – Junction Temperature – °C TJ – Junction Temperature – °C Figure 11. Power Good Threshold Voltage vs Junction Temperature Figure 12. Soft-Start Voltage vs Junction Temperature Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 7 Detailed Description 7.1 Overview The TPS4030x is a family of cost-optimized synchronous buck controllers providing high-end features to construct high-performance DC–DC converters. Prebias capability eliminates concerns about damaging sensitive loads during start-up. Programmable overcurrent protection levels and hiccup overcurrent fault recovery maximize design flexibility and minimize power dissipation in the event of a prolonged output short. The Frequency Spread Spectrum (FSS) feature reduces peak EMI noise by spreading the initial energy of each harmonic along a frequency band, thus giving a wider spectrum with lower amplitudes. 7.2 Functional Block Diagram + 10mA Soft Start 0.6 VREF + 12.5% SS SS EN/SS 2 SD BP 10 COMP 4 FB 6-V Regulator 1 + References OC SD Spread Spectrum Oscillator Clock PWM Logic 5 7 HDRV 8 SW 9 LDRV/OC BP Anti-Cross Conduction and Prebias Circuit + 10mA 0.6 VREF PGOOD BOOT PWM + SS 6 0.6 VREF BP Calibration Circuit BP 0.6 VREF –12.5% Fault Controller Clock VDD FB + Thermal Shutdown 750 kW 3 OC Threshold Setting Fault Controller OC PAD UDG-09160 GND 7.3 Feature Description 7.3.1 Voltage Reference The 600-mV band gap cell is internally connected to the noninverting input of the error amplifier. The reference voltage is trimmed with the error amplifier in a unity gain configuration to remove amplifier offset from the final regulation voltage. The 1% tolerance on the reference voltage allows the user to design a very accurate power supply. 7.3.2 Enable Functionality, Start-Up Sequence and Timing After input power is applied, an internal current source of 40 µA starts to charge up the soft-start capacitor connected from EN/SS to GND. When the voltage across that capacitor increases to 0.7 V, it enables the internal BP regulator followed by a calibration. The total calibration time is about 1.9 ms. See Figure 13. During the calibration, the device performs in the following way. It disables the LDRV drive and injects an internal 10-µA current source to the resistor connected from LDRV to GND. The voltage developed across that resistor is then sampled and latched internally as the OCP trip level until one cycles the input or toggles the EN/SS. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 9 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com Feature Description (continued) 2.0 VIN – Input Voltage – V VEN/SS 1.6 Calibration Time 1.9 ms 1.3 V 1.2 0.8 0.7 V 0.4 VSS_INT 0 t – Time – ms UDG-09159 Figure 13. Start-Up Sequence and Timing The voltage at EN/SS is internally clamped to 1.3 V before and/or during calibration to minimize the discharging time once calibration. The discharging current is from an internal current source of 140 µA and it pulls the voltage down to 0.4 V. The discharging current then initiates the soft-start by charging up the capacitor using an internal current source of 10 µA. The resulting voltage ramp on this pin is used as a second noninverting input to the error amplifier after an 800 mV (typical) downward level-shift; therefore, actual soft-start does not occur until the voltage at this pin reaches 800 mV. If EN/SS is left floating, the controller starts automatically. EN/SS must be pulled down to less than 270 mV to ensure that the chip is in shutdown mode. 7.3.3 Soft-Start Time The soft-start time of the TPS4030x is user programmable by selecting a single capacitor. The EN/SS pin sources 10 µA to charge this capacitor. The actual output ramp-up time is the amount of time that it takes for the 10 µA to charge the capacitor through a 600-mV range. There is some initial lag due to calibration and an offset (800 mV) from the actual EN/SS pin voltage to the voltage applied to the error amplifier. The soft-start is done in a closed-loop fashion, meaning that the error amplifier controls the output voltage at all times during the soft-start period and the feedback loop is never open as occurs in duty cycle limit soft-start schemes. The error amplifier has two non-inverting inputs, one connected to the 600-mV reference voltage, and the other connected to the offset EN/SS pin voltage. The lower of these two voltages is what the error amplifier controls the FB pin. As the voltage on the EN/SS pin ramps up past approximately 1.4 V (800-mV offset voltage plus the 600 mV reference voltage), the 600-mV reference voltage becomes the dominant input and the converter has reached its final regulation voltage. The capacitor required for a given soft-start ramp time for the output voltage is given by Equation 1. æI ö CSS = ç SS ÷ ´ t SS è VFB ø where • • • • 10 CSS is the required capacitance on the EN/SS pin. (F) ISS is the soft-start source current (10 µA). VFB is the feedback reference voltage (0.6 V). tSS is the desired soft-start ramp time (s). Submit Documentation Feedback (1) Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 Feature Description (continued) 7.3.4 Oscillator and Frequency Spread Spectrum (FSS) The oscillator frequency is internally fixed. The TPS40303 operating frequency is 300 kHz, the TPS40304 operating frequency is 600 kHz, and the TPS40305 operating frequency is 1.2 MHz. Connecting a resistor with a value of 267 kΩ ±10% from BP to EN/SS enables the FSS feature. When the FSS is enabled, it spreads the internal oscillator frequency over a minimum 12% window using a 25-kHz modulation frequency with triangular profile. By modulating the switching frequency, side-bands are created. The emission power of the fundamental switching frequency and its harmonics is distributed into smaller pieces scattered around many sideband frequencies. The effect significantly reduces the peak EMI noise and makes it much easier for the resultant emission spectrum to pass EMI regulations. 7.3.5 Overcurrent Protection Programmable OCP level at LDRV is from 6 mV to 150 mV at room temperature with 3000 ppm temperature coefficient to help compensate for changes in the low-side FET channel resistance as temperature increases. With a scale factor of 2, the actual trip point across the low-side FET is in the range of 12 mV to 300 mV. The accuracy of the internal current source is ±5%. Overall offset voltage, including the offset voltage of the internal comparator and the amplifier for scale factor of 2, is limited to ±8 mV. Maximum clamp voltage at LDRV is 340 mV to avoid turning on the low-side FET during calibration and in a prebiased condition. The maximum clamp voltage is fixed and it does not change with temperature. If the voltage drop across ROCSET reaches the 340-mV maximum clamp voltage during calibration (no ROCSET resistor included), it disables OC protection. Once disabled, there is no low-side or high-side current sensing. OCP level at HDRV is fixed at 450 mV with 3000-ppm temperature coefficient to help compensate for changes in the high-side FET channel resistance as temperature increases. OCP at HDRV provides pulse-by-pulse current limiting. OCP sensing at LDRV is a true inductor valley current detection, using sample and hold. Equation 2 can be used to calculate ROCSET: ææ ö æI öö ç ç IOUT(max ) - ç P-P ÷ ÷ ´ RDS(on ) - VOCLOS ÷ è 2 øø ç ÷ ROCSET = ç è ÷    2 ´ IOCSET ç ÷ ç ÷ è ø where • • • • • • IOCSET is the internal current source. VOCLOS is the overall offset voltage. IP-P is the peak-to-peak inductor current. RDS(on) is the drain to source ON-resistance of the low-side FET. IOUT(max) is the trip point for OCP. ROCSET is the resistor used for setting the OCP level. (2) To avoid overcurrent tripping in normal operating load range, calculate ROCSET using the equation above with: • The maximum RDS(ON) at room temperature • The lower limit of VOCLOS (–8 mV) and the lower limit of IOCSET (9.5 µA) from the Electrical Characteristics table. • The peak-to-peak inductor current IP-P at minimum input voltage Overcurrent is sensed across both the low-side FET and the high-side FET. If the voltage drop across either FET exceeds the OC threshold, a count increments one count. If no OC is detected on either FET, the fault counter decrements by one count. If three OC pulses are summed, a fault condition is declared which cycles the softstart function in a hiccup mode. Hiccup mode consists of four dummy soft-start timeouts followed by a real one if overcurrent condition is encountered during normal operation, or five dummy soft-start timeouts followed by a real one if overcurrent condition occurs from the beginning during start. This cycle continues indefinitely until the fault condition is removed. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 11 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com Feature Description (continued) 7.3.6 Drivers The drivers for the external high-side and low-side MOSFETs can drive a gate-to-source voltage of VBP. The LDRV driver for the low-side MOSFET switches between BP and GND, while the HDRV driver for the high-side MOSFET is referenced to SW and switches between BOOT and SW. The drivers have nonoverlapping timing that is governed by an adaptive delay circuit to minimize body diode conduction in the synchronous rectifier. 7.3.7 Prebias Start-Up The TPS4030x contains a circuit to prevent current from being pulled from the output during start-up in the condition the output is prebiased. There are no PWM pulses until the internal soft-start voltage rises above the error amplifier input (FB pin), if the output is prebiased. Once the soft-start voltage exceeds the error amplifier input, the controller slowly initiates synchronous rectification by starting the synchronous rectifier with a narrow on time. The controller then increments that on time on a cycle-by-cycle basis until it coincides with the time dictated by (1-D), where D is the duty cycle of the converter. This approach prevents the sinking of current from a prebiased output, and ensures the output voltage start-up and ramp to regulation is smooth and controlled. 7.3.8 Power Good The TPS4030x provides an indication that output is good for the converter. This is an open-drain signal and pulls low when any condition exists that would indicate that the output of the supply might be out of regulation. These conditions include the following: • VFB is more than ±12.5% from nominal. • Soft-start is active. • A short-circuit condition has been detected. NOTE When there is no power to the device, PGOOD is not able to pull close to GND if an auxiliary supply is used for the power good indication. In this case, a built-in resistor connected from drain to gate on the PGOOD pulldown device makes the PGOOD pin look approximately like a diode to GND. 7.3.9 Thermal Shutdown If the junction temperature of the device reaches the thermal shutdown limit of 145°C, the PWM and the oscillator are turned off and HDRV and LDRV are driven low. When the junction cools to the required level (125°C typical), the PWM initiates soft-start as during a normal power-up cycle. 12 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 7.4 Device Functional Modes 7.4.1 Modes of Operation 7.4.1.1 UVLO In UVLO, VDD is less than UVLO_ON, the BP6 regulator is off, and the HDRV and LDRV are held low by internal passive discharge resistors. 7.4.1.2 Disable Disable is forced by holding SS/EN below 0.4 V. In disable, the BP6 regulator is off, and both HDRV and LDRV are held low by passive discharge resistors. 7.4.1.3 Calibration Each enable of the TPS4030X3/4/5 devices requires a calibration which lasts approximately 2 ms. During calibration the TPS40303/4/5 devices LDRV and HDRV are held off by their respective pulldown drivers while the device configures as detailed in Enable Functionality, Start-Up Sequence and Timing. 7.4.1.4 Converting When calibration completes, the TPS40303/4/5 devices ramp their reference voltage as described in Soft-Start Time, and the states of the LDRV and HDRV drivers are dictated by the COMP pin to regulate the FB pin equal to the internal reference. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 13 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 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 TPS4030x is a family of cost-optimized synchronous buck controllers providing high-end features to construct high-performance DC-DC converters. Prebias capability eliminates concerns about damaging sensitive loads during start-up. Programmable overcurrent protection levels and hiccup overcurrent fault recovery maximize design flexibility and minimize power dissipation in the event of a prolonged output short. Frequency Spread Spectrum (FSS) feature reduces peak EMI noise by spreading the initial energy of each harmonic along a frequency band, thus giving a wider spectrum with lower amplitudes. 8.2 Typical Applications 8.2.1 Using the TPS40305 for a 12-V to 1.8-V Point-of-Load Synchronous Buck Regulator Figure 14 shows 12-V to 1.8-V at 10-A synchronous buck application using the TPS40305 switching at 1200 kHz. + 4 Copyright © 2017, Texas Instruments Incorporated Figure 14. TPS40305 Design Example Schematic 14 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 Typical Applications (continued) 8.2.1.1 Design Requirements For this example, follow the design parameters listed in Table 1. Table 1. Design Example Electrical Characteristics PARAMETER TEST CONDITIONS MIN TYP MAX VIN Input voltage VIN(ripple) Input ripple IOUT = 10 A 8 VOUT Output voltage 0 A ≤ IOUT ≤ 10 A Line regulation 8 V ≤ VIN ≤ 14 V 0.5% Load regulation 0 A ≤ IOUT ≤ 10 A 0.5% VRIPPLE Output ripple IOUT = 10 A VOVER Output overshoot IOUT falling from 7 A to 3 A VUNDER Output undershoot IOUT rising from 3 A to 7 A IOUT Output current 4.5 V ≤ VIN ≤ 5.5 V tSS Soft-start time VIN = 12 V ISCP Short-circuit current trip point fSW Switching frequency 1.764 1.800 UNIT 14 V 0.6 V 1.836 V 36 mV 100 mV 100 0 mV 10 A 1.5 13 Size ms 15 A 1200 kHz 1 in2 The bill of materials for this application is shown in Table 2. The efficiency, line, and load regulation from boards built using this design are shown in Figure 14. Gerber files and additional application information are available from the factory. Table 2. Design Example List of Materials REFERENCE DESIGNATOR QTY C1 C2 VALUE DESCRIPTION SIZE PART NUMBER MFR 1 3.3 nF Capacitor, Ceramic, 10 V, X7R, 20% 0603 Std Std 1 820 pF Capacitor, Ceramic, 25 V, X7R, 10% 0603 Std Std C3 1 150 pF Capacitor, Ceramic, 25 V, X7R, 10% 0603 Std Std C4 1 3300 pF Capacitor, Ceramic, 25 V, X7R, 10% 0603 Std Std C5 1 1.0 µF Capacitor, Ceramic, 10 V, X7R, 20% 0805 Std Std C6 1 100 nF Capacitor, Ceramic, 16 V, X7R, 20% 0603 Std Std C7 1 1 µF Capacitor, Ceramic, 25 V, X7R, 20% 0805 Std Std C8 2 10 µf Capacitor, Ceramic, 25 V, X7R, 10% 1210 Std Std C11 1 330 µF Capacitor, Aluminum, 25 V, ±20%, 160 mΩ 0.328 × 0.390 inch EEVFK1E331P Panasonic C12 2 22 µF Capacitor, Ceramic, 6.3 V, X5R, 20% 0805 Std Std L1 1 0.32 µH Inductor, SMT, 17 A 0.268 × 0.268 inch PG0083.401 Pulse Q1 1 MOSFET, N-Channel, 25 V, 97 A, 4.6 mΩ QFN-8 POWER CSD16322Q5 TI Q2 1 MOSFET, N-Channel, 25 V, 59 A, 9.6 mΩ QFN-8 POWER CSD16410Q5A TI R3 1 422 Ω Resistor, Chip, 1/16W, 1% 0603 Std Std R4 1 10.0 kΩ Resistor, Chip, 1/16W, 1% 0603 Std Std R5 1 4.99 kΩ Resistor, Chip, 1/16W, 1% 0603 Std Std R6 1 2.20 kΩ Resistor, Chip, 1/16W, 1% 0603 Std Std R8 1 100 kΩ Resistor, Chip, 1/16W, 1% 0603 Std Std R10 1 2Ω Resistor, Chip, 1/16W, 1% 0603 Std Std R11 1 3.74 kΩ Resistor, Chip, 1/16W, 1% 0603 Std Std U1 1 IC, 3-V to 20-V sync. 1.2-MHz Buck controller DRC10 TPS40305DRC TI Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 15 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 8.2.1.2 Detailed Design Procedure 8.2.1.2.1 Custom Design With WEBENCH® Tools Click here to create a custom design using the TPS4030x devicse 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. 8.2.1.2.2 Selecting the Switching Frequency To achieve the small size for this design, the TPS40305, with fSW = 1200 kHz, is selected for minimal external component size. 8.2.1.2.3 Inductor Selection (L1) Synchronous buck power inductors are typically sized for approximately 30% peak-to-peak ripple current (IRIPPLE) Given this target ripple current, the required inductor size can be calculated in Equation 3. VIN(max) – VOUT V 1 14 V – 1.8 V 1.8 V 1 × OUT × = × × = 471 nH L 0.3 × I OUT VIN(max) f SW 0.3 × 10 A 14 V 1200 kHz " (3) Selecting a standard 400-nH inductor value, solve for IRIPPLE = 3.5 A The RMS current through the inductor is approximated by Equation 4. IL(rms ) = IL(avg)2 + 2 1 I 12 RIPPLE = IOUT 2 + 2 1 I 12 RIPPLE = 102 + 1 3.52 12 = 10.05 A (4) 8.2.1.2.4 Output Capacitor Selection (C12) The selection of the output capacitor is typically driven by the output transient response. Equation 5 and Equation 6 overestimate the voltage deviation to account for delays in the loop bandwidth and can be used to determine the required output capacitance. 2 I I I I ´L ´L VOVER < TRAN ´ DT = TRAN ´ TRAN = TRAN COUT COUT VOUT VOUT ´ COUT VUNDER < (5) ITRAN2 ´L ´L ITRAN I I ´ DT = TRAN ´ TRAN = COUT COUT VIN - VOUT (VIN - VOUT )´ COUT (6) If VIN(min) > 2 × VOUT, use overshoot (Equation 5) to calculate minimum output capacitance. If VIN(min) < 2 × VOUT, use undershoot (Equation 6) to calculate minimum output capacitance. COUT(min) = ITRAN(max)2 ´ L (VOUT )´ VOVER = 42 ´ 400nH = 35 mF 1.8 ´ 100mV (7) With a minimum capacitance, the maximum allowable ESR is determined by the maximum ripple voltage and is approximated by Equation 8. 16 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 æ ö IRIPPLE VRIPPLE(total) - ç ÷ VRIPPLE(total) - VRIPPLE(cap) è 8 ´ COUT ´ fSW ø ESRMAX = = IRIPPLE IRIPPLE æ ö 3.5 A 36mV - ç ÷ è 8 ´ 35 mF ´ 1200kHz ø = 7mW = 3.5 A (8) Two 0805, 22-µF, 6.3-V, X5R ceramic capacitors are selected to provide more than 35 µF of minimum capacitance and less than 7 mΩ of ESR (2.5 mΩ each). 8.2.1.2.5 Peak Current Rating of Inductor With output capacitance, it is possible to calculate the charge current during start-up and determine the minimum saturation current rating for the inductor. The start-up charging current is approximated by Equation 9. V ´ COUT 1.8 V ´ 2 ´ 22 mF ICHARGE = OUT = = 0.053 A tSS 1.5ms (9) IL(peak ) = IOUT(max) + 12 IRIPPLE + ICHARGE = 10 A + 12 ´ 3.5 A + 0.053 A = 11.8 A (10) Table 3. Inductor Requirements SYMBOL L PARAMETER Inductance VALUE UNIT 400 nH IL(rms) RMS current (thermal rating) 10.05 A IL(peak) Peak current (saturation rating) 11.8 A A PG0083.401, 400-nH inductor is selected for its small size, low DCR (3.0 mΩ) and high-current handling capability (17-A thermal, 27-A saturation). 8.2.1.2.6 Input Capacitor Selection (C8) The input voltage ripple is divided between capacitance and ESR. For this design VRIPPLE(cap) = 150 mV and VRIPPLE(esr) = 150 mV. The minimum capacitance and maximum ESR are estimated by Equation 11. ILOAD ´ VOUT 10 ´ 1.8 V = = 12.5 mF CIN(min) = VRIPPLE(cap) ´ VIN ´ fSW 150mV ´ 8 V ´ 1200kHz (11) ESR MAX = VRIPPLE(esr ) ILOAD + 1 2 IRIPPLE = 150 mV = 12.7 m W 11.75 A (12) The RMS current in the input capacitors is estimated by Equation 13. IRM S (cin ) = ILO A D ´ D ´ (1 - D ) = 10 A ´ 0.225 ´ (1 - 0.225 ) = 4.17 A RM S   (13) Two 1210, 10-µF, 25-V, X5R ceramic capacitors with approximately 2-mΩ of ESR and a 2.5-A RMS current rating each are selected. Higher voltage capacitors are selected to minimize capacitance loss at the DC bias voltage to ensure the capacitors allow sufficient capacitance at the working voltage. 8.2.1.2.7 MOSFET Switch Selection (Q1 and Q2) Reviewing available TI NexFET MOSFETs using TI’s NexFET MOSFET selection tool, the CSD16410Q5A and CSD16322Q5 5-mm × 6-mm MOSFETs are selected. These two FETs have maximum total gate charges of 5 nC and 10 nC, respectively, which draws 18 mA at 1.2 MHz from the BP regulator, less than its 50 mA minimum rating. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 17 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 8.2.1.2.8 Bootstrap Capacitor (C6) To ensure proper charging of the high-side FET gate, limit the ripple voltage on the boost capacitor to less than 50 mV. CBOOST = 20 ´ QG2 = 20 ´ 5nC = 100nF (14) 8.2.1.2.9 VDD Bypass Capacitor (C7) Per the TPS40305 Electrical Characteristics specifications, select a 1.0-µF X5R or better ceramic bypass capacitor for VDD. 8.2.1.2.10 BP Bypass Capacitor (C5) As listed in the Electrical Characteristics, a minimum of 1.0-µF ceramic capacitance is required to stabilize the BP regulator. To limit regulator noise to less than 10 mV, the value of the bypass capacitor is calculated in Equation 15. CBP = 100 ´ MAX(QG1,QG2 ) (15) Because Q1 is larger than Q2, and the total gate charge of Q1 is 10 nC, a BP capacitor of 1.0 µF is calculated. A standard value of 1.0 µF is selected to limit noise on the BP regulator. 8.2.1.2.11 Short-Circuit Protection (R11) The TPS40305 uses the negative drop across the low-side FET at the end of the OFF time to measure the inductor current. Allowing for 30% over maximum load and 20% rise in RDS(on)Q1 for self-heating, the voltage drop across the low-side FET at current limit is given by Equation 16. VOC = (1.3 × ILOAD – 21 IRIPPLE ) × 1.2 × R DS (on) Q1 = (1.3 ×10 A – 21 3.5 A) × 1.2 × 4.6 mΩ = 62.1 mV (16) The TPS40305 internal temperature coefficient helps compensate for the RDS(on) temperature coefficient of the MOSFET, so the current limit programming resistor is selected by Equation 17. RCS = VOC – VOCLOS(min) 2 × IOCSET(min) = 62.1mV – (– 8mV) = 3.69 kΩ 2 × 9.5 mA ! 3.74 kΩ (17) 8.2.1.2.12 Feedback Divider (R4, R5) The TPS40305 controller uses a full operational amplifier with an internally fixed 0.600-V reference. R4 is selected between 10 kΩ and 50 kΩ for a balance of feedback current and noise immunity. With R4 set to 10 kΩ, The output voltage is programmed with a resistor divider given by Equation 18. VFB ´ R4 0.600 V ´ 10.0kW R5 = = = 5.0kW » 4.99kW VOUT - VFB 1.8 V - 0.600 V (18) 8.2.1.2.13 Compensation: (C2, C3, C4, R3, R6) Using the TPS40k Loop Stability Tool for 100-kHz bandwidth and 60° phase margin with a R4 value of 10.0 kΩ, the following values are returned. • C2 = C_1 = 820 pF • C3 = C_3 = 150 pF • C4 = C_2 = 3300 pF • R3 = R_2 = 422 Ω • R6 = R_3 = 2.20 kΩ 18 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 8.2.1.3 Application Curves 100 180 90 VIN = 8 V 40 90 20 45 0 0 -20 85 135 h – Efficiency – % Gain – dB 60 95 Phase – ° 80 225 Phase VIN = 14 V IOUT = 10 A BW = 82 kHz Phase Margin 55° VIN = 12 V 80 VIN = 14 V 75 70 65 -45 Gain 60 -90 -40 55 -60 0.1 1 10 100 -135 1k 50 0 f – Frequency – kHz Figure 15. Gain and Phase vs Frequency 4 2 6 8 10 ILOAD – Load Current – A Figure 16. Efficiency vs Load Current Figure 17. Output Ripple (500-MHz Bandwidth) Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 19 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 8.2.2 A High-Current, Low-Voltage Design Using the TPS40304 For this 20-A, 12-V to 1.2-V design, the 600-kHz TPS40304 was selected for a balance between small size and high efficiency. + + 1 Copyright © 2017, Texas Instruments Incorporated Figure 18. TPS40304 Design Example Schematic 8.2.2.1 Design Requirements For this example, follow the design parameters listed in Table 4. Table 4. Design Example Electrical Characteristics PARAMETER TEST CONDITIONS MIN TYP 8 MAX VIN Input voltage VINripple Input ripple IOUT = 20 A VOUT Output voltage 0 A ≤ IOUT ≤ 20 A Line regulation 8 V ≤ VIN ≤ 14 V 0.5% 0.5% 1.164 1.200 Load regulation 0 A ≤ IOUT ≤ 20 A VRIPPLE Output ripple IOUT = 20 A VOVER Output overshoot 5 A ≤ IOUT ≤ 15 A 100 VUNDER Output undershoot 5 A ≤ IOUT ≤ 15 A 100 IOUT Output current 8 V ≤ VIN ≤ 14 V tSS Soft-start time VIN = 12 V ISCP Short-circuit current trip point fSW Switching frequency V 0.5 V 1.236 V 36 0 mV mV mV 20 A 1.5 ms 600 kHz 26 Size UNIT 14 A 1.5 in2 8.2.2.2 Detailed Design Procedure 8.2.2.2.1 Selecting the Switching Frequency To achieve the small size for this design the TPS40304, with fSW = 600 kHz, is selected for minimal external component size. 8.2.2.2.2 Inductor Selection (L1) Synchronous buck power inductors are typically sized for approximately 30% peak-to-peak ripple current (IRIPPLE) Given this target ripple current, the required inductor size can be calculated in Equation 19. VIN(max) - VOUT V 1 14V - 1.2V 1.2V 1 L» ´ OUT ´ = ´ ´ = 305nH 0.3 ´ IOUT VIN(max) FSW 0.3 ´ 20A 14V 600kHz (19) Selecting a standard 300-nH inductor value, solve for IRIPPLE = 6 A 20 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 The RMS current through the inductor is approximated by Equation 20. I Lrms = I Lavg2 + 2 1 I 12 RIPPLE I OUT2 + = 2 1 I 12 RIPPLE = 202 + 112 62 = 20.07 A (20) 8.2.2.2.3 Output Capacitor Selection (C12) The selection of the output capacitor is typically driven by the output transient response. Equation 21 and Equation 22 overestimate the voltage deviation to account for delays in the loop bandwidth and can be used to determine the required output capacitance. 2 I I I I ´L ´L VOVER < TRAN ´ DT = TRAN ´ TRAN = TRAN COUT COUT VOUT VOUT ´ COUT VUNDER < (21) ITRAN2 ´L ´L ITRAN I I ´ DT = TRAN ´ TRAN = COUT COUT VIN - VOUT (VIN - VOUT )´ COUT (22) If VIN(min) > 2 × VOUT, use overshoot (Equation 21) to calculate minimum output capacitance. If VIN(min) < 2 × VOUT, use undershoot (Equation 22) to calculate minimum output capacitance. COUT(MIN) = ITRAN(MAX)2 ´ L (VOUT )´ VOVER = 102 ´ 300nH = 250mF 1.2 ´ 100mV (23) With a minimum capacitance, the maximum allowable ESR is determined by the maximum ripple voltage and is approximated by Equation 24. ESRmax = VRIPPLE(Total) - VRIPPLE(CAP) IRIPPLE æ ö IRIPPLE æ ö 6A VRIPPLE(total) - ç ÷ 36mV - ç ÷ ´ ´ 8 C F ´ m ´ 8 250 F 600kHz OUT SW ø è è ø = 5.2mW = = IRIPPLE 6A (24) Two 47-µF and one 220-µF capacitors are selected to provide more than 250 µF of minimum capacitance and 5.2 mΩ of ESR. 8.2.2.2.4 Peak Current Rating of Inductor With output capacitance, it is possible to calculate the charge current during start-up and determine the minimum saturation current rating for the inductor. The start-up charging current is approximated by Equation 25. ICHARGE = VOUT × COUT 1.2 V(2 × 47 mF + 220 m F) = 0.251 A = TSS 1.5 ms IL _ PEAK = I OUT(max) + 1 2 IRIPPLE + I CHARGE = 20 A +1 2 (25) × 6 A + 0.2512 A = 23.25 A (26) Table 5. Inductor Requirements PARAMETER VALUE UNIT 300 nH RMS current (thermal rating) 20.07 A Peak current (saturation rating) 23.25 A L Inductance IL(rms) IL(peak) Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 21 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 8.2.2.2.5 Input Capacitor Selection (C8) The input voltage ripple is divided between capacitance and ESR. For this design VRIPPLE(cap) = 150 mV and VRIPPLE(esr) = 150 mV. The minimum capacitance and maximum ESR are estimated by Equation 27. ILOAD ´ VOUT 20 ´ 1.2V = = 33.3uF CIN(min) = VRIPPLE(CAP) ´ VIN ´ FSW 150mV ´ 8V ´ 600kHz (27) ESRMAX = VRIPPLE(ESR) ILOAD + 1 I 2 RIPPLE = 150 mV = 6.5 mW 23A (28) The RMS current in the input capacitors is estimated by Equation 29. IRMS _ CIN = ILOAD ´ D ´ (1 – D) = 20 A ´ 0.15 ´ (1 - 0.15) = 7.14 Arms (29) Three 1210, 10-µF, 25-V, X5R ceramic capacitors are selected. Higher voltage capacitors are selected to minimize capacitance loss at the DC bias voltage to ensure the capacitors allow sufficient capacitance at the working voltage. 8.2.2.2.6 MOSFET Switch Selection (Q1 and Q2) Reviewing available TI NexFET MOSFETs using the TI NexFET MOSFET selection tool, the CSD16410Q5A and CSD16321Q5 5-mm × 6-mm MOSFETs are selected. These two FETs have maximum total gate charges of 5 nC and 10 nC, respectively. 8.2.2.2.7 Bootstrap Capacitor (C6) To ensure proper charging of the high-side FET gate, limit the ripple voltage on the boost capacitor to less than 50 mV. CBoost = 20 ´ QG1 = 20 ´ 5 nC = 100 nF (30) 8.2.2.2.8 VDD Bypass Capacitor (C7) Per the TPS40304 data sheet, select a 1.0-uF X5R or better ceramic bypass capacitor for VDD. 8.2.2.2.9 BP Bypass Capacitor (C5) Per the TPS40304 data sheet, a minimum 1.0-uF ceramic capacitance is required to stabilize the BP regulator. To limit regulator noise to less than 10 mV, the value of the bypass capacitor is calculated in Equation 31. CBP = 100 ´ MAX(QG1,QG2 ) (31) Because Q2 is larger than Q1, and the total gate charge of Q2 is 10 nC, a BP capacitor of 1.0 µF is calculated. A standard value of 1.0 µF is selected to limit noise on the BP regulator. 8.2.2.2.10 Short-Circuit Protection (R11) The TPS40304 uses the negative drop across the low-side FET at the end of the OFF time to measure the inductor current. Allowing for 30% over maximum load and 20% rise in RDS(on)Q1 for self-heating, the voltage drop across the low-side FET at current limit is given by Equation 32. VOC = (1.3 ´ ILOAD - 21 Iripple ) ´ 1.2 ´ RDSONG2 = (1.3 ´ 20 A- 21 6 A) ´ 1.2 ´ 4.6 mW = 127 mV (32) The TPS40304 internal temperature coefficient helps compensate for the MOSFET RDS(on) temperature coefficient, so the current limit programming resistor is selected by Equation 33. RCS = 22 VOC - VOCLOS(min) 2 ´ IOCSET(min) = 127 mV - (– 8 mV) = 7.1 kW 2 ´ 9.5 mA Submit Documentation Feedback (33) Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 8.2.2.2.11 Feedback Divider (R4, R5) The TPS40304 controller uses a full operational amplifier with an internally fixed 0.6-V reference. R4 is selected between 10 kΩ and 50 kΩ for a balance of feedback current and noise immunity. With R4 set to 10 kΩ, The output voltage is programmed with a resistor divider given by Equation 34. VFB ´ R4 0.600 V ´ 10.0 kW R7 = = = 10 kW VOUT - VFB 1.2 V - 0.600 V (34) 8.2.2.2.12 Compensation: (C2, C3, C4, R3, R6) Using the TPS40k Loop Stability Tool for 100-kHz bandwidth and 60° phase margin with a R4 value of 10.0 kΩ, the following values are returned. • C4 = 680 pF • C5 = 100 pF • C6 = 680 pF • R1 = 10 kΩ • R2 = 1.5 kΩ Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 23 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 8.2.2.3 Application Curves 100 225 90 80 180 85 60 135 40 90 20 45 0 0 95 VIN = 14 V 80 75 VIN = 12 V 70 Phase – ° Phase Gain – dB h – Efficiency – % VIN = 8 V 65 –20 –45 Gain 60 –40 –90 55 –60 1k 50 0 5 10 15 10 k 100 k –135 1M 20 f – Frequency – Hz ILOAD – Load Current – A Figure 20. Gain and Phase vs Frequency Figure 19. Efficiency vs Load Current Figure 21. Output Ripple 10 mV/div, 2-µs/div, 20-MHz Bandwidth 24 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 8.2.3 A Synchronous Buck Application Using the TPS40303 Figure 22 shows a 3.3-V/5-V/12-V to 0.6-V at 10-A synchronous buck application using the TPS40303 switching at 300 kHz. 0.6 + + Copyright © 2017, Texas Instruments Incorporated Figure 22. TPS40303 Design Example Schematic 8.2.3.1 Design Requirements For this example, follow the design parameters listed in Table 6. Table 6. Design Example Electrical Characteristics PARAMETER TEST CONDITIONS MIN TYP 3.3 MAX VIN Input voltage VINripple Input ripple IOUT = 10 A VOUT Output voltage 0 A ≤IOUT ≤ 10 A Line regulation 3 V ≤ VIN ≤14 V 0.5% Load regulation 0 A ≤IOUT ≤ 10 A 0.5% VRIPPLE Output ripple IOUT = 10 A VOVER Output overshoot 3 A ≤ IOUT ≤ 7 A 100 VUNDER Output undershoot 3 A ≤IOUT ≤ 7 A 100 IOUT Output current 3.3 V ≤ VIN ≤ 14 V tSS Soft-start time VIN = 12 V ISCP Short-circuit current trip point Efficiency fSW 0.582 Switching frequency V 0.6 V 0.618 V 12 0 13 VIN = 12 V, IOUT = 5 A 0.6 UNIT 14 mV mV 10 ms 15 A 84% kHz 1.5 Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 A 1.5 300 Size mV Submit Documentation Feedback in2 25 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 8.2.3.2 Detailed Design Procedure 8.2.3.2.1 Selecting the Switching Frequency To achieve the small size for this design the TPS40303, with fSW = 300 kHz, is selected for minimal external component size. 8.2.3.2.2 Inductor Selection (L1) Synchronous buck power inductors are typically sized for approximately 30% peak-to-peak ripple current (IRIPPLE) Given this target ripple current, the required inductor size can be calculated in Equation 35. VIN(max) - VOUT V 1 14V - 0.6V 0.6V 1 L» ´ OUT ´ = ´ ´ = 638nH 0.3 ´ IOUT VIN(max) FSW 0.3 ´ 10A 14V 300kHz (35) Selecting a standard 600-nH inductor value, solve for IRIPPLE = 3.2 A The RMS current through the inductor is approximated by Equation 36. ILrms = ILavg2 + 2 1 I 12 RIPPLE = IOUT 2 + 2 1 I 12 RIPPLE = 102 + 1 3.22 12 = 10.04A (36) 8.2.3.2.3 Output Capacitor Selection (C12) The selection of the output capacitor is typically driven by the output transient response. Equation 37 and Equation 38 overestimate the voltage deviation to account for delays in the loop bandwidth and can be used to determine the required output capacitance. 2 I I I I ´L ´L VOVER < TRAN ´ DT = TRAN ´ TRAN = TRAN COUT COUT VOUT VOUT ´ COUT VUNDER < (37) ITRAN2 ´L ´L ITRAN I I ´ DT = TRAN ´ TRAN = COUT COUT VIN - VOUT (VIN - VOUT )´ COUT (38) If VIN(min) > 2 × VOUT, use overshoot (Equation 37) to calculate minimum output capacitance. If VIN(min) < 2 × VOUT, use undershoot (Equation 38) to calculate minimum output capacitance. COUT(MIN) = ITRAN(MAX)2 ´ L (VOUT) ´ VOVER = 42 ´ 600 nH = 160 mF 0.6 ´ 100 mV (39) With a minimum capacitance, the maximum allowable ESR is determined by the maximum ripple voltage and is approximated by Equation 40. ESRmax = VRIPPLE(Total) - VRIPPLE(CAP) IRIPPLE æ ö IRIPPLE æ ö 3.2 A VRIPPLE(total) - ç ÷ 36 mV - ç 8 ´ COUT ´ FSW ø 8 ´ 160 mF ´ 300 kHzø÷ è è = = = 8.6 mW IRIPPLE 3.2 A (40) Two 560-µF capacitors are selected to provide more than 160-µF of minimum capacitance and less than 8.6 mΩ of ESR. 26 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 8.2.3.2.4 Peak Current Rating of Inductor With output capacitance, it is possible to calculate the charge current during start-up and determine the minimum saturation current rating for the inductor. The start-up charging current is approximated by Equation 41. ´ COUT 0.6 V(2 ´ 560 mF) V ICHARGE = OUT = 0.448 A = TSS 1.5 ms (41) IL _ PEAK = IOUT(max) + 1 2 IRIPPLE + ICHARGE = 10A + 1 2 ´ 3.2A + 0.448A = 12.05A (42) Table 7. Inductor Requirements PARAMETER VALUE UNIT 600 nH RMS current (thermal rating) 10.04 A Peak current (saturation rating) 12.05 A L Inductance IL(rms) IL(peak) 8.2.3.2.5 Input Capacitor Selection (C8) The input voltage ripple is divided between capacitance and ESR. For this design VRIPPLE(cap) = 150 mV and VRIPPLE(esr) = 150 mV. The minimum capacitance and maximum ESR are estimated by Equation 43. CIN(min) = ESRMAX = ILOAD ´ VOUT 10 ´ 0.6 V = = 40.4 uF VRIPPLE(CAP) ´ VIN ´ FSW 150 mV ´ 3.3 V ´ 300 kHz VRIPPLE(ESR) ILOAD + 1 I 2 RIPPLE 150 mV = = 13 mW 11.6 A (43) (44) The RMS current in the input capacitors is estimated by Equation 45. IRMS _ CIN = ILOAD ´ D ´ (1 - D) = 10 A ´ 0.2 ´ (1 - 0.2) = 4 Arms (45) Five 1210, 10-µF, 25-V, X5R ceramic capacitors with approximately 2-mΩ of ESR and a 2.5-A RMS current rating each are selected. Higher voltage capacitors are selected to minimize capacitance loss at the DC bias voltage to ensure the capacitors allow sufficient capacitance at the working voltage. 8.2.3.2.6 MOSFET Switch Selection (Q1 and Q2) Reviewing available TI NexFET MOSFETs using the TI NexFET MOSFET selection tool, the CSD16323Q3 and CSD16323Q3 5-mm × 6-mm MOSFETs are selected. These two FETs have maximum total gate charges of 8.4 nC. 8.2.3.2.7 Bootstrap Capacitor (C6) To ensure proper charging of the high-side FET gate, limit the ripple voltage on the boost capacitor to less than 50 mV. CBoost = 20 ´ QG1 = 20 ´ 8.4 nC = 100 nF Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 (46) Submit Documentation Feedback 27 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 8.2.3.2.8 VDD Bypass Capacitor (C7) Per the TPS40305 Electrical Characteristics specifications, select a 1.0-µF X5R or better ceramic bypass capacitor for VDD. 8.2.3.2.9 BP Bypass Capacitor (C5) Per the TPS40303 data sheet, a minimum 1.0-uF ceramic capacitance is required to stabilize the BP regulator. To limit regulator noise to less than 10 mV, the value of the bypass capacitor is calculated in Equation 47. CBP = 100 ´ MAX(QG1,QG2 ) (47) Because both Q1 and Q2’s are the same, total gate charge is 8.4 nC, a BP capacitor of 0.84 µF is calculated. A standard value of 1.0 uF is selected to limit noise on the BP regulator. 8.2.3.2.10 Short-Circuit Protection (R11) The TPS40305 uses the negative drop across the low-side FET at the end of the OFF time to measure the inductor current. Allowing for 30% over maximum load and 20% rise in RDS(on)Q1 for self-heating, the voltage drop across the low-side FET at current limit is given by Equation 48. VOC = (1.3 ´ ILOAD - 21 Iripple ) ´ 1.2 ´ RDSONQ2 = (1.3 ´ 10A - 21 3.2A) ´ 1.2 ´ 4.4mW = 60mV (48) The TPS40305 internal temperature coefficient helps compensate for the MOSFET’s RDS(on) temperature coefficient, so the current limit programming resistor is selected by Equation 49. VOC - VOCLOS(min) 60 mV - (- 8 mV) = = 3.6 kW RCS = 2 ´ IOCSET(min) 2 ´ 9.5 mA (49) 8.2.3.2.11 Feedback Divider (R4, R5) The TPS40305 controller uses a full operational amplifier with an internally fixed 0.600-V reference. R5 is selected between 10 kΩ and 50 kΩ for a balance of feedback current and noise immunity. With R5 set to 10 kΩ, the output voltage is programmed with a resistor divider given by Equation 50. Because the feedback voltage is equal to output voltage, low-side voltage divider resistor is not needed. VFB ´ R5 RLowside = VOUT - VFB (50) 8.2.3.2.12 Compensation: (C2, C3, C4, R3, R6) Using the TPS40k Loop Stability Tool for 100-kHz bandwidth and 60° phase margin with a R5 value of 10 kΩ, the following values are returned. • C8 = 10 nF • C14 = 270 pF • C15 = 4.7 nF • R6 = 2.74 kΩ • R3 = 1 kΩ 28 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 8.2.3.3 Application Curves A typical efficiency graph for this design example using the TPS40303 is shown in Figure 23.The typical line and load regulation this design example using the TPS40303 is shown in Figure 24 100 601 VIN = 3.3 V 90 600 VIN = 3.3 V VOUT – Output Voltage – V 80 h – Efficiency – % 70 VIN = 5 V 60 50 VIN = 12 V 40 30 599 598 597 VIN = 5 V 596 595 20 VIN = 12 V 594 10 593 0 2 8 6 4 10 0 2 8 10 Figure 24. Line and Load Regulation Figure 23. Efficiency vs Load Current 80 60 200 Gain Phase 175 40 150 20 125 0 100 -20 75 -40 50 -60 25 -80 10 20 6 ILOAD – Load Current – A ILOAD – Load Current – A Gain (dB) 4 50 100 1000 10000 Frequency (Hz) 100000 Phase (°) 0 0 1000000 D001 D008 D002 Figure 25. Total System Bode 9 Power Supply Recommendations These devices are designed to operate from an input voltage supply between 3 V and 20 V. This input supply should remain within the input voltage supply range. This supply must be well regulated. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 29 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 10 Layout 10.1 Layout Guidelines • • • • • • • • • • • • • • • • • • 30 For MOSFET or Power Block Layout, follow the layout recommendations provided for the MOSFET or Power Block selected. Connect VDD to VIN as close as possible to the drain connection of the high-side FET to avoid introducing additional drop which could trigger short-circuit protection. Place VDD and BP to GND capacitors within 2 mm of the device and connected to the Thermal Pad (GND). The FB to GND resistor should connect to the thermal tab (GND) with a minimum 10-mil wide trace. Place VOUT to FB resistor within 2 mm of the FB pin. The EN/SS-to-GND capacitor must connect to the thermal tab (GND) with a minimum 10-mil-wide trace. It may share this trace with FB to GND. If a BJT or MOSFET is used to disable EN/SS, place it within 5 mm of the device. If a COMP to GND resistor is used, place it within 5 mm of the device. All COMP and FB traces should be kept minimum line width and as short as possible to minimize noise coupling. Do not route EN/SS more than 20 mm from the device. If multiple layers are used, extend GND under all components connected to FB, COMP and EN/SS to reduce noise sensitivity. HDRV and LDRV should provide short, low inductance paths of 5 mm or less to the gates of the MOSFETs or Power Block. No more than 1 Ω of resistance should be placed between HDRV or LDRV and their MOSFET or Power Block gate pins. LDRV / OC to GND Current Limit Programming resistor may be placed on the far side of the MOSFET if necessary to ensure a short connection from LDRV to the gate of the low-side MOSFET. The BOOT to SW resistor and capacitor should both be placed within 4 mm of the device using a minimum of 10-mil-wide trace. The full width of the component pads are preferred for trace widths if design rules allow. If via must be used between the HDRV, SW and LDRV pins and their respective MOSFET or Power Block connections, use a minimum of two vias to reduce parasitic inductance Refer to the Land Pattern Data for the preferred layout of thermal vias within the thermal pad. It is recommended to extend the top-layer copper area of the thermal pad (GND) beyond the package a minimum 3 mm between pins 1 and 10 and 5 and 6 to improve thermal resistance to ambient of the device. Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 10.2 Layout Example Figure 26. Top Copper With Components .. .. Figure 27. Top Internal Copper Layout .. .. Figure 28. Bottom Internal Copper Layout Figure 29. Bottom Copper Layer Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 31 TPS40303, TPS40304, TPS40305 SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 www.ti.com 11 Device and Documentation Support 11.1 Device Support 11.1.1 Third-Party Products Disclaimer TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE. 11.2 Custom Design With WEBENCH® Tools Click here to create a custom design using the TPS4030x devices 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. 11.3 Documentation Support 11.3.1 Related Documentation These references, design tools and links to additional references, including design software, may be found at http://power.ti.com 1. Additional PowerPAD™ information may be found in Applications Briefs (SLMA002) and (SLMA004). 2. Under The Hood Of Low Voltage DC/DC Converters – SEM1500 Topic 5 – 2002 Seminar Series 3. Understanding Buck Power Stages in Switchmode Power Supplies, (SLVA057), March 1999 4. Designing Stable Control Loops – SEM 1400 – 2001 Seminar Series 11.4 Related Links The table below lists quick access links. Categories include technical documents, support and community resources, tools and software, and quick access to sample or buy. Table 8. Related Links PARTS PRODUCT FOLDER SAMPLE & BUY TECHNICAL DOCUMENTS TOOLS & SOFTWARE SUPPORT & COMMUNITY TPS40303 Click here Click here Click here Click here Click here TPS40304 Click here Click here Click here Click here Click here TPS40305 Click here Click here Click here Click here Click here 11.5 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. 32 Submit Documentation Feedback Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 TPS40303, TPS40304, TPS40305 www.ti.com SLUS964D – NOVEMBER 2009 – REVISED MARCH 2018 11.6 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. 11.7 Trademarks E2E is a trademark of Texas Instruments. WEBENCH is a registered trademark of Texas Instruments. All other trademarks are the property of their respective owners. 11.8 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. 11.9 Glossary SLYZ022 — TI Glossary. This glossary lists and explains terms, acronyms, and definitions. 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. Copyright © 2009–2018, Texas Instruments Incorporated Product Folder Links: TPS40303 TPS40304 TPS40305 Submit Documentation Feedback 33 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) TPS40303DRCR ACTIVE VSON DRC 10 3000 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 125 0303 TPS40303DRCT ACTIVE VSON DRC 10 250 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 125 0303 TPS40304DRCR ACTIVE VSON DRC 10 3000 RoHS & Green NIPDAUAG Level-2-260C-1 YEAR -40 to 125 0304 TPS40304DRCT ACTIVE VSON DRC 10 250 RoHS & Green NIPDAUAG Level-2-260C-1 YEAR -40 to 125 0304 TPS40305DRCR ACTIVE VSON DRC 10 3000 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 125 0305 TPS40305DRCT ACTIVE VSON DRC 10 250 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 125 0305 (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
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TPS40304DRCR
  •  国内价格 香港价格
  • 1+17.049301+2.05850
  • 10+14.4371010+1.74310
  • 100+12.25630100+1.47980
  • 250+11.59160250+1.39960
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  • 1000+8.349701000+1.00810
  • 3000+7.778303000+0.93910
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  • 9000+7.335109000+0.88560

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