BQ24380DSGR

Product Folder Sample & Buy Support & Community Tools & Software Technical Documents bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 bq2438x Overvoltage and Overcurrent Protection IC and Li+ Charger Front-End Protection IC With LDO Mode 1 Features 3 Description • • • • • • • • • • • The bq2438x family of devices are charger front-end integrated circuits (ICs) designed to provide protection to Li-ion batteries from failures of the charging circuit. The device continuously monitors the input voltage and battery voltage. The device operates like a linear regulator, maintaining a 5.5-V (bq24380) or 5-V (bq24381, bq24382) output with input voltages up to the Input overvoltage threshold. During input overvoltage conditions, the device immediately turns off the internal pass FET disconnecting the charging circuit from the damaging input source. Additionally, if the battery voltage rises to unsafe levels while charging, power is removed from the system. The device checks for short-circuit or overload conditions at its output when turning the pass FET on, and if it finds unsafe conditions, it switches off and then rechecks the conditions. Additionally, the device also monitors its die temperature and switches off if it exceeds 140°C. 1 Input Overvoltage Protection Accurate Battery Overvoltage Protection Output Short-Circuit Protection Soft-Start to Prevent Inrush Currents Soft-Stop to Prevent Voltage Spikes Maximum Input Voltage of 30 V Supports up to 1.7-A Load Current Thermal Shutdown Enable Function Fault Status Indication Small 2 mm × 2 mm 8-Pin WSON Package 2 Applications • • • • Smart Phones, Mobile Phones PDAs MP3 Players Low-Power Handheld Devices When the device is controlled by a processor, the device provides status information about fault conditions to the host. Device Information(1) PART NUMBER PACKAGE BODY SIZE (NOM) bq24380 bq24381 WSON (8) 2.00 mm × 2.00 mm bq24382 (1) For all available packages, see the orderable addendum at the end of the data sheet. Simplified Schematic AC Adapter OUT 8 1 IN VDC GND Charging Circuit 1 mF 1 mF bq24380 SYSTEM VBAT 6 VSS 2 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. bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 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 6.7 4 4 4 4 5 6 7 Absolute Maximum Ratings ...................................... ESD Ratings ............................................................ Recommended Operating Conditions....................... Thermal Information .................................................. Electrical Characteristics........................................... Timing Requirements ................................................ Typical Characteristics .............................................. Detailed Description .............................................. 9 7.1 Overview ................................................................... 9 7.2 Functional Block Diagram ......................................... 9 7.3 Feature Description................................................. 10 7.4 Device Functional Modes........................................ 11 8 Application and Implementation ........................ 12 8.1 Application Information............................................ 12 8.2 Typical Application ................................................. 12 9 Power Supply Recommendations...................... 15 10 Layout................................................................... 15 10.1 Layout Guidelines ................................................. 15 10.2 Layout Example .................................................... 15 11 Device and Documentation Support ................. 16 11.1 11.2 11.3 11.4 11.5 Related Links ........................................................ Community Resources.......................................... Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 16 16 16 16 16 12 Mechanical, Packaging, and Orderable Information ........................................................... 16 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision B (March 2009) to Revision C Page • Added ESD Ratings table, Thermal Information, Timing Requirements, Functional Block Diagram, Design Requirements, Application Curves, Power Supply Recommendations, Layout Example, Device and Documentation Support, and Mechanical, Packaging, and Orderable Information......................................................................................... 1 • Changed SON to WSON throughout the document............................................................................................................... 1 • Changed From: "the bq2430x CE pin." To: "the bq2438x CE pin." in Selection of R(BAT) ................................................... 13 • Moved Figures 1 through 8 from Typical Characteristics to Application Curves section ..................................................... 13 Changes from Revision A (May 2008) to Revision B Page • Added device bq24382 to the datasheet................................................................................................................................ 1 • Added the bq24382 option to IDD in the Electrical Characteristics. ........................................................................................ 5 • Added the bq24382 option to VO(REG) in the Electrical Characteristics................................................................................... 5 • Added the bq24382 option to VOVP in the Electrical Characteristics ...................................................................................... 5 • Added the bq24382 option to Vhys(OVP) in the Electrical Characteristics ................................................................................. 5 Changes from Original (April 2008) to Revision A Page • Changed Figure 4 .................................................................................................................................................................. 7 • Changed Figure 5 .................................................................................................................................................................. 7 • Added Figure 9 ...................................................................................................................................................................... 7 2 Submit Documentation Feedback Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 bq24380, bq24381, bq24382 www.ti.com SLUS805C – APRIL 2008 – REVISED AUGUST 2015 5 Pin Configuration and Functions DSG Package 8-Pin WSON With Exposed Thermal Pad Top View IN 1 8 OUT VSS 2 7 NC NC 3 6 VBAT FAULT 4 5 CE Pin Functions PIN NAME NO. I/O DESCRIPTION CE 5 I Active-low chip enable input. Connect CE = HI to turn the input pass FET off. Connect CE = LOW to turn the internal pass FET on and connect the input to the charging circuitry. CE is Internally pulled down, approximately 200 kΩ. FAULT 4 O Open-drain device status output. FAULT is pulled to VSS internally when the input pass FET has been turned off due to input overvoltage or output short-circuit conditions, an overtemperature condition, or because the battery voltage is outside safe limits. FAULT is high impedance during normal operation. IN 1 I Input power, connected to external DC supply. Bypass IN to VSS with a ceramic capacitor (1 μF minimum) NC 3, 7 Output terminal to the charging system. Bypass OUT to VSS with a ceramic capacitor (1 μF minimum) 6 I Battery voltage sense input. Connected to pack positive terminal through a 100-kΩ resistor. 2 – Ground terminal. Connect to the thermal pad and to the ground rail of the circuit. 8 VBAT VSS Thermal PAD Do not connect to any external circuits. These pins may have internal connections used for test purposes. O OUT There is an internal electrical connection between the exposed thermal pad and the VSS pin of the device. The thermal pad must be connected to the same potential as the VSS pin on the printed-circuit board. Do not use the thermal pad as the primary ground input for the device. VSS pin must be connected to ground at all times. Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 Submit Documentation Feedback 3 bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 www.ti.com 6 Specifications 6.1 Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted) All voltage values are with respect to the network ground terminal unless otherwise noted. (1) VI Input voltage IOUTmax MIN MAX IN (with respect to VSS) –0.3 30 OUT (with respect to VSS) –0.3 12 FAULT, CE, VBAT (with respect to VSS) –0.3 7 UNIT V Output source current OUT 2 A Output sink current FAULT 15 mA TJ Junction temperature –40 150 °C Tstg Storage temperature –65 150 °C (1) 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. 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 JESD22C101 (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 MIN VI IN voltage range IO Output current, OUT pin TJ Junction temperature NOM MAX UNIT 3.3 30 V 1.7 A –40 125 °C 6.4 Thermal Information bq2438x THERMAL METRIC (1) DSG (WSON) UNIT 8 PINS RθJA Junction-to-ambient thermal resistance 64 °C/W RθJC(top) Junction-to-case (top) thermal resistance 84.1 °C/W RθJB Junction-to-board thermal resistance 33.9 °C/W ψJT Junction-to-top characterization parameter 1.9 °C/W ψJB Junction-to-board characterization parameter 34.3 °C/W RθJC(bot) Junction-to-case (bottom) thermal resistance 5.8 °C/W (1) 4 For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953. Submit Documentation Feedback Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 bq24380, bq24381, bq24382 www.ti.com SLUS805C – APRIL 2008 – REVISED AUGUST 2015 6.5 Electrical Characteristics Over junction temperature range –40°C ≤ TJ ≤ 125°C and recommended supply voltage (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT IN UVLO Undervoltage lock-out, input power detected threshold CE = LO or HI, VIN: 0 V → 3 V Vhys(UVLO) Hysteresis on UVLO CE = LO or HI, VIN: 3 V → 0 V IDD ISTDBY CE = LO, no load on OUT pin, VIN = 5 V Operating current Standby current 2.5 2.8 V 200 300 mV bq24380 250 bq24381 300 bq24382 300 μA CE = HI, VIN = 5.5 V 100 μA 280 mV 10 μA INPUT-TO-OUTPUT CHARACTERISTICS VDO Dropout voltage IN to OUT CE = LO, VIN = 5 V, I(OUT) = 1 A IOFF Q1 off-state leakage current CE = HI, VIN = 5.5 V INPUT OVERVOLTAGE PROTECTION VO(REG) VOVP Output voltage CE = LO, VIN = 6 V Input overvoltage protection threshold CE = LO, VIN: 5 V → 8 V CE = LO or HI, VIN: 7 V → 5 V Vhys(OVP) Hysteresis on OVP CE = LO or HI, VIN: 8 V → 5 V bq24380 5.3 5.5 5.7 bq24381 4.8 5 5.2 bq24382 4.8 5 5.2 bq24380 6.1 6.3 6.5 bq24831 6.88 7.1 7.31 bq24382 10.17 10.5 10.83 bq24380 25 110 bq24831 25 120 bq24382 150 300 V V mV OUTPUT SHORT-CIRCUIT PROTECTION (ONLY at START-UP) IO(SC) Short-circuit detection threshold tREC(SC) Retry interval if short-circuit detected 3 V < VIN < VOVP - Vhys(OVP) 1.3 1.5 1.7 64 A ms BATTERY OVERVOLTAGE PROTECTION BVOVP Battery overvoltage protection threshold VIN > 4.5 V, CE = LO 4.3 Vhys(BVovp) Hysteresis on BV(OVP) VIN > 4.5 V, CE = LO 200 I(VBAT) Input bias current on VBAT pin TJ = 25°C 4.35 4.4 V 320 mV 10 nA 150 °C THERMAL PROTECTION TJ(OFF) Thermal shutdown temperature TJ(OFF-HYS) Thermal shutdown hysteresis 140 20 °C LOGIC LEVELS ON CE VIL Logic LOW input voltage 0 VIH Logic HIGH input voltage 1.4 0.4 V 1 μA V CE = 1.8 V 15 μA IIL IIH V LOGIC LEVELS ON FAULT VOL Output LOW voltage ISINK = 5 mA 0.2 V Ilkg Off-state leakage current, HI-Z V FAULT = 5 V 10 μA Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 Submit Documentation Feedback 5 bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 www.ti.com 6.6 Timing Requirements MIN NOM MAX UNIT IN CE = LO or HI. Time measured from VIN 0 V → 5 V 1-μs rise-time Deglitch time, input power detected status tDGL(PGOOD) 8 ms 200 ns 8 ms 176 μs INPUT OVERVOLTAGE PROTECTION tPD(OVP) (1) tREC(OVP) Input OV propagation delay VIN: 5 V → 10 V Recovery time from input overvoltage condition CE = LO. Time measured from V IN: 7 V → 5 V, 1-μs fall-time BATTERY OVERVOLTAGE PROTECTION (1) VIN > 4.5 V, CE = LO, Time measured from VVSAT rising from 4.1 V to 4.4 V to FAULT going low. Deglitch time, battery overvoltage detected tDGL(BVovp) Not tested. Specified by design tSStart tCHK(SC) t tSStopREC(SC) tSStart tPD(OVP) tDGL(BVOVP) tDGL(PGOOD) tREC(OVP) 5 VOVP VOVP-Vhys(OVP) VO(REG) Input Voltage UVLO 2 4 2 2 4 6 VO(REG) 1 Output Voltage 7 IO(SC) Output Current CE FAULT 3 BV(OVP) BV(OVP)-Vhys(BVOVP) Battery Voltage 1. Short-circuit during start-up 2. Normal start-up condition 3. Battery overvoltage event 4. VUVLO < VIN < V(OREG) – VOUT tracks VIN 5. Input overvoltage event 6. Input below UVLO 7. High-current event during normal operation Figure 1. Timing Diagram 6 Submit Documentation Feedback Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 bq24380, bq24381, bq24382 www.ti.com SLUS805C – APRIL 2008 – REVISED AUGUST 2015 6.7 Typical Characteristics 250 2.75 IOUT = 1 A 210 VIN Rising DROPOUT VOLTAGE - mV UVLO - Undervoltage Lockout - V 2.70 2.65 2.60 2.55 2.50 VIN Falling VIN = 4 V 170 VIN = 5 V 130 90 2.45 2.40 -40 -15 10 35 60 85 TA - Free-Air Temperature - °C 110 50 -40 135 -15 10 35 60 85 110 135 TA - Free-Air Temperature - °C Figure 2. UVLO vs Free-Air Temperature Figure 3. Dropout Voltage vs Free-Air Temperature 5.60 7.4 bq24381 VIN Rising 7.2 bq24380 5.40 VOVP – Threshold – V VOUT(REG) – Output Voltage – V 5.50 5.30 5.20 5.10 7.0 VIN Falling 6.8 6.6 VIN Rising 6.4 bq24381 6.2 5.00 4.90 –40 –15 10 35 60 85 110 bq24380 6.0 –40 135 –15 TA – Free-Air Temperature – °C VIN Falling 10 35 60 85 TA – Free-Air Temperature – °C 110 135 Figure 5. OVP Threshold vs Free-Air Temperature Figure 4. Output Voltage Regulation, VO(REG) vs Free-Air Temperature 4.40 25 4.35 IIkg - Bat Leakage Current - nA VBOVP - Threshold - V VBAT Rising 4.30 4.25 4.20 4.15 15 10 5 VBAT Falling 4.10 4.05 -40 20 -15 10 35 60 85 TA - Free-Air Temperature - °C 110 135 Figure 6. OVP Threshold, VBOVP vs Free-Air Temperature 0 -40 -15 10 35 60 85 TA - Free-Air Temperature - °C 110 135 Figure 7. Leakage Current (VBAT PIN) vs Free-Air Temperature Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 Submit Documentation Feedback 7 bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 www.ti.com Typical Characteristics (continued) 1000 1000 900 900 VO(REG) 700 IC Enabled 600 500 400 300 IC Disabled 200 IC Enabled 600 500 400 300 IC Disabled 100 0 5 10 15 20 VIN – Input Voltage – V 25 30 Figure 8. Supply Current vs Input Voltage (bq24380) 8 700 200 100 0 VO(REG) 800 ICC – Supply Current – mA ICC – Supply Current – mA 800 Submit Documentation Feedback 0 0 5 10 15 20 VIN – Input Voltage – V 25 30 Figure 9. Supply Current vs Input Voltage (bq24381) Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 bq24380, bq24381, bq24382 www.ti.com SLUS805C – APRIL 2008 – REVISED AUGUST 2015 7 Detailed Description 7.1 Overview The bq2438x is a highly integrated circuit designed to provide protection to Li-ion batteries from failures of the charging circuit and the input source. The device continuously monitors the input voltage and the battery voltage. The device operates like a linear regulator, maintaining a 5.5-V (bq24380) or 5-V (bq24381, bq24382) output with input voltages up to the input overvoltage threshold (VOVP). If the input voltage exceeds VOVP, the device shuts off the pass FET and disconnects the system from input power. Additionally, if the battery voltage rises above 4.35 V, the device switches off the pass FET, removing the power from the system until the battery voltage falls to safe levels. The device also monitors its die temperature and switches the pass FET off if it exceeds 140°C. The device can be controlled by a processor, and also provides status information about fault conditions to the host. 7.2 Functional Block Diagram Q1 IN OUT Output Regulation Loop VO(REG) 1.5A Short Circuit protection Disabled after startup Chargepump Supply FAULT VOVP COUNTERS, CONTROL, AND STATUS OVP CE tDGL(PGOOD) VBAT VIN VBG VBG UVLO THERMAL SHUTDOWN tDGL(BOVP) VSS Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 Submit Documentation Feedback 9 bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 www.ti.com 7.3 Feature Description 7.3.1 Input Overvoltage Protection The OUT output of the bq2438x operates similar to a linear regulator. While the input voltage is less than VO(REG) and above the UVLO, the output voltage tracks the input voltage (less the drop caused by RDS(on) of the pass FET). When the input voltage is greater than VO(REG) (plus the RDS(on) drop) and less than VOVP, the output voltage is regulated to VO(REG). VO(REG) is 5.5 V for the bq24380 and 5 V for both the bq24381 and bq24382. If the input voltage is increased above VOVP, the internal pass FET is turned off, removing power from the charging circuitry connected to OUT. The FAULT output is then asserted low. When the input voltage drops below VOVP – Vhys(OVP) (but is still above UVLO), the pass FET is turned on after a deglitch time of tREC(OVP) to ensure that the input supply has stabilized. The condition 5 in Figure 1 illustrates an input overvoltage event. 7.3.2 Battery Overvoltage Protection The battery overvoltage threshold BVOVP is internally set to 4.35 V for the bq2438x. Condition 3 in Figure 1 illustrates a battery overvoltage event. If the battery voltage exceeds the BVOVP threshold for longer than tDGL(BVovp), the pass FET is turned off (using soft-stop), and FAULT is asserted low. The pass FET is turned on (using the soft-start sequence) once the battery voltage drops to BVOVP – Vhys(BVovp). 7.3.3 Thermal Protection If the junction temperature of the device exceeds TJ(OFF), the pass FET is turned off and the FAULT output is asserted low. The FET is turned back on when the junction temperature falls below TJ(OFF) – TJ(OFF-HYS). 7.3.4 Start-Up Short-Circuit Protection The bq2438x features overload current protection during start-up. The condition 1 in Figure 1 illustrates start-up into an overload condition. If after the eight soft-start steps are complete and the current limit is exceeded, the device initiates a short-circuit check timer (tCHK(SC)). During this check, the current is clamped to IO(SC). If the 5-ms tCHK(SC) timer expires and the current remains clamped by the current limit, the internal pass FET is turned off using the soft-stop method, FAULT is pulled low, and the tREC(SC) timer begins. Once the tREC(SC) timer expires, FAULT becomes high impedance and the soft-start sequence restarts. The device repeats the start/fail sequence until the overload condition is removed. Once the overload condition is removed, the current-limit circuitry is disabled and the device enters normal operation. Additionally, if the current is not limited after the completion of the soft-start sequence, the tCHK(SC) timer does not start and the current limit circuitry is disabled for normal operation. 7.3.5 Enable Function The device has an enable pin which is used to enable and disable the device. Connect the CE pin high to turn off the internal pass FET. Connect the CE pin low to turn on the internal pass FET and enter the start-up routine. The CE pin has an internal pulldown resistor and can be left unconnected. The FAULT pin is high impedance when the CE pin is high. 7.3.6 Fault Indication The FAULT pin is an active-low, open-drain output. It is in a high-impedance state when operating conditions are safe, or when the device is disabled by setting CE high. With CE low, the FAULT pin goes low whenever any of these events occurs: 1. Output short-circuit at power-on 2. Input overvoltage 3. Battery overvoltage 4. IC overtemperature See Figure 1 for an example of FAULT conditions during these events. Connect the FAULT pin to the desired logic-level voltage rail through a resistor between 1 kΩ and 50 kΩ. 10 Submit Documentation Feedback Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 bq24380, bq24381, bq24382 www.ti.com SLUS805C – APRIL 2008 – REVISED AUGUST 2015 7.4 Device Functional Modes 7.4.1 OPERATION Mode The bq2438x device continuously monitors the input voltage and the battery voltage. As long as the input voltage is less than VOVP, the output voltage tracks the input voltage (less the drop caused by RDSON of Q1). During fault conditions, the internal FET is turned off and the output is isolated from the input source. 7.4.2 POWER-DOWN Mode The device remains in POWER-DOWN mode when the input voltage at the IN pin is below the undervoltage threshold (UVLO) of 2.8 V. The FET connected between the IN and OUT pins is off, and the status output, FAULT, is set to HI-Z. 7.4.3 POWER-ON RESET Mode The device resets when the input voltage at the IN pin exceeds the UVLO threshold. During power-on reset, the device waits for duration tDGL(PGOOD) for the input voltage to stabilize. If, after tDGL(PGOOD), the input voltage and battery voltage are within operation limits, the pass FET is turned ON. The device has a soft-start feature to control the inrush current. The soft-start minimizes the ringing at the input due to the resonant circuit formed by the parasitic inductance of the adapter cable and the input bypass capacitor. During the soft-start time, tSStart, the current limit is stepped up in 8 equal steps every 625 μs. Each step is one-eighth of the IO(SC). After the soft-start sequence is over, the device samples the load current. If the load current exceeds IO(SC), the device initiates short circuit protection. See the Startup Short-Circuit Protection section for details. If no overcurrent event is measured, the current-monitoring circuitry is disabled for normal operation. In the event a short-circuit is detected at power-on, to prevent the input voltage from spiking up when the pass FET is switched off (due to the inductance of the input cable), The pass FET is turned off by gradually reducing its gate-drive, resulting in a soft-stop (tSStop). Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 Submit Documentation Feedback 11 bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 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 bq2438x device protects against overvoltage and battery overvoltage events that occur due to faulty adapter or incorrect input sources. If either of these faults occur, the bq2438x device isolates the downstream devices from the input source and alerts the host controller with the FAULT open-drain output. 8.2 Typical Application AC Adapter OUT 8 1 IN VDC GND 1 mF 1 mF Charging Circuit RBAT VBAT 6 100 kW SYSTEM bq24380 FAULT 4 VSS 2 RPU 47 kW RFAULT 47 kW RCE 47 kW CE 5 Figure 10. Typical Application Circuit 8.2.1 Design Requirements For this design example, use the parameters shown in Table 1. Table 1. Design Parameters PARAMETER VALUE Voltage 5V Current < 1.5 A 8.2.2 Detailed Design Procedure 8.2.2.1 Selection of R(BAT) It is strongly recommended that the battery not be tied directly to the VBAT pin of the device, as under some failure modes of the device, the voltage at the IN pin may appear on the VBAT pin. This voltage can be as high as 30 V, and applying 30 V to the battery may cause failure of the device and can be hazardous. Connecting the VBAT pin through R(BAT) prevents a large current from flowing into the battery in the event of failure of the device. For safety, R(BAT) must have a high value. The problem with a large R(BAT) is that the voltage drop across this resistor because of the VBAT bias current, I(VBAT), causes an error in the BVOVP threshold. This error is over and above the tolerance on the nominal 4.35-V BVOVP threshold. 12 Submit Documentation Feedback Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 bq24380, bq24381, bq24382 www.ti.com SLUS805C – APRIL 2008 – REVISED AUGUST 2015 Choosing R(BAT) in the range from 100 kΩ to 470 kΩ is a good compromise. If the device fails with R(BAT) equal to 100 kΩ, the maximum current flowing into the battery would be (30 V – 3 V) ÷ 100 kΩ = 246 μA, which is low enough to be absorbed by the bias currents of the system components. R(BAT) equal to 100 kΩ results in a worstcase voltage drop of R(BAT) × I(VBAT) = 1 mV. This is negligible compared to the internal tolerance of 50 mV on the BVOVP threshold. If the Bat-OVP function is not required, the VBAT pin must be connected to VSS. 8.2.2.2 Selection of R(CE) The CE pin can be used to enable and disable the device. If host control is not required, the CE pin can be tied to ground or left unconnected, permanently enabling the device. In applications where external control is required, the CE pin can be controlled by a host processor. As with the VBAT pin (see previous discussion), the CE pin must be connected to the host GPIO pin through as large a resistor as possible. The limitation on the resistor value is that the minimum VOH of the host GPIO pin less the drop across the resistor must be greater than VIH of the bq2438x CE pin. The drop across the resistor is given by R(CE) × IIH. 8.2.2.3 Selection of Input and Output Bypass Capacitors The input capacitor CIN in Figure 10 is for decoupling and serves an important purpose. Whenever there is a step change downwards in the system load current, the inductance of the input cable causes the input voltage to spike up. CIN prevents the input voltage from overshooting to dangerous levels. It is recommended that a ceramic capacitor of at least 1 μF be used at the input of the device. It must be located in close proximity to the IN pin. COUT in Figure 10 is also important. During an overvoltage transient, this capacitance limits the output overshoot until the power FET is turned off by the overvoltage protection circuitry. COUT must be a ceramic capacitor of at least 1 μF, located close to the OUT pin. COUT also serves as the input decoupling capacitor for the charging circuit downstream of the protection device. 8.2.3 Application Curves ROUT = 6.6 W VIN 5 V/div VIN 2 V/div VOUT 500 mV/div VOUT 2 V/div IOUT 500 mA/div t - Time - 2 ms/div Figure 11. Normal Power-On vs Showing Soft-Start (bq24380) VFAULT 2 V/div t - Time - 2 ms/div Figure 12. OVP at Power-On Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 Submit Documentation Feedback 13 bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 www.ti.com VIN = 6 V to 9 V step VFAULT 2 V/div VFAULT 2 V/div VIN 2 V/div VIN 2 V/div VOUT 2 V/div VOUT 2 V/div t - Time - 5 ms/div Figure 13. OVP Response for Input Step (bq24380) t - Time - 200 ms/div Figure 14. Slow Input Ramp into OVP Event (bq24380) VIN = 10 V to 6 V step VIN 5 V/div VIN 5 V/div VOUT 5 V/div VFAULT 2 V/div VOUT 2 V/div IOUT 1 A/div VFAULT 2 V/div t - Time - 2 ms/div Figure 15. Recovery from OVP (bq24380) t - Time - 5 ms/div Figure 16. Power Up into Short Circuit VBAT 1 V/div VIN 5 V/div VOUT 2 V/div VOUT 500 mV/div VFAULT 2 V/div IOUT 1 A/div VBAT = 3.8 V to 4.5 V step t - Time - 50 ms/div t - Time - 20 ms/div Figure 17. Soft-Stop During OCP Event (bq24380) 14 Submit Documentation Feedback Figure 18. Battery OVP Event (bq24380) Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 bq24380, bq24381, bq24382 www.ti.com SLUS805C – APRIL 2008 – REVISED AUGUST 2015 9 Power Supply Recommendations The intention is for the bq2438x device to operate with 5-V adapters with a maximum current rating of 1.5 A. The device operates from sources from 3 V to 5.7 V. Outside of this range, the output is disconnected due to either UVLO or the OVP function. 10 Layout 10.1 Layout Guidelines • • • This device is a protection device and is meant to protect down-stream circuitry from hazardous voltages. Potentially, high voltages may be applied to this device. It has to be ensured that the edge-to-edge clearances of PCB traces satisfy the design rules for the maximum voltages expected to be seen in the system. See Figure 19. The device uses WSON packages with a thermal pad. For good thermal performance, the thermal pad must be thermally coupled with the PCB ground plane (GND). In most applications, this requires a copper pad directly under the device. This copper pad must be connected to the ground plane with an array of thermal vias. CIN and COUT should be located close to the device. Other components like R(BAT) should also be located close to the device. 10.2 Layout Example GND VOUT /FAULT GND GND BAT+ VBAT VIN Figure 19. Layout Example Recommendation Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 Submit Documentation Feedback 15 bq24380, bq24381, bq24382 SLUS805C – APRIL 2008 – REVISED AUGUST 2015 www.ti.com 11 Device and Documentation Support 11.1 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 2. Related Links PARTS PRODUCT FOLDER SAMPLE & BUY TECHNICAL DOCUMENTS TOOLS & SOFTWARE SUPPORT & COMMUNITY bq24380 Click here Click here Click here Click here Click here bq24381 Click here Click here Click here Click here Click here bq24382 Click here Click here Click here Click here Click here 11.2 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. 11.3 Trademarks E2E is a trademark of Texas Instruments. All other trademarks are the property of their respective owners. 11.4 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. 11.5 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. 16 Submit Documentation Feedback Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: bq24380 bq24381 bq24382 PACKAGE OPTION ADDENDUM www.ti.com 14-Oct-2022 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) Samples (4/5) (6) BQ24380DSGR ACTIVE WSON DSG 8 3000 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 125 CFE Samples BQ24380DSGT ACTIVE WSON DSG 8 250 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 125 CFE Samples BQ24381DSGR ACTIVE WSON DSG 8 3000 RoHS & Green NIPDAUAG Level-2-260C-1 YEAR -40 to 125 CFW Samples BQ24381DSGT ACTIVE WSON DSG 8 250 RoHS & Green NIPDAUAG Level-2-260C-1 YEAR -40 to 125 CFW Samples BQ24382DSGR ACTIVE WSON DSG 8 3000 RoHS & Green NIPDAUAG Level-2-260C-1 YEAR -40 to 125 OBE Samples BQ24382DSGT ACTIVE WSON DSG 8 250 RoHS & Green NIPDAUAG Level-2-260C-1 YEAR -40 to 125 OBE Samples (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