ZHCSNY0B May 2020 – January 2023 BQ25798
PRODUCTION DATA
PIN | I/O | DESCRIPTION | |
---|---|---|---|
NAME | NO. | ||
STAT | 1 | DO | Open Drain Charge Status Output – It indicates various charger operations. Connect to the pull up rail via a 10kΩ resistor. LOW indicates charging in progress. HIGH indicates charging completed or charging disabled. When any fault condition occurs, STAT pin blinks at 1Hz. The STAT pin function can be disabled when DIS_STAT bit is set to 1. |
VBUS | 2-3 | P | Charger Input Voltage – The power input terminal of the charger. An input current sensing circuit is connected between VBUS and PMID. The recommended capacitors at VBUS are 2 pieces of 10μF and one piece of 0.1μF ceramic capacitors. Place the 0.1μF ceramic capacitor as close as possible to the charger IC. |
BTST1 | 4 | P | Input High Side Power MOSFET Gate Driver Power Supply – Connect a 10V or higher rating, 47nF ceramic capacitor between SW1 and BTST1 as the bootstrap capacitor for driving high side switching MOSFET (Q1). |
REGN | 5 | P | The Charger Internal Linear Regulator Output – It is supplied from either VBUS or BAT dependent on which voltage is higher. Connect a 10V, 4.7μF ceramic capacitor from REGN to power ground. The REGN LDO output is used for the internal MOSFETs gate driving voltage and the voltage bias for TS pin resistor divider. |
D+ | 6 | AIO | Positive Line of the USB Data Line Pair – D+/D- based USB host/charging port detection for VIN1 input. The detection includes data contact detection (DCD), primary and secondary detection in BC1.2, and the adjustable high voltage adapter. |
D- | 7 | AIO | Negative Line of the USB Data Line Pair – D+/D- based USB host/charging port detection for VIN1 input. The detection includes data contact detection (DCD), primary and secondary detection in BC1.2, and the adjustable high voltage adapter. |
VAC2 | 8 | P | VAC2 Input Detection – When a voltage between 3.6V and 24V is applied on VAC2, it represents a valid input being plugged into port #2. Connect to VBUS if the ACFET2 and RBFET2 are not installed. |
VAC1 | 9 | P | VAC1 Input Detection – When a voltage between 3.6V and 24V is applied on VAC1, it represents a valid input being plugged into port #1. Connect to VBUS if the ACFET1 and RBFET1 are not installed. |
ACDRV2 | 10 | P | Input FETs Driver Pin 2 – The charge pump output to drive the port #2 input N-channel MOSFET (ACFET2) and the reverse blocking N-channel MOSFET (RBFET2). The charger turns on the back-to-back MOSFETs by increasing the ACDRV2 voltage 5V above the common source connection of the ACFET2 and RBFET2 when the turn-on condition is met. Tie ACDRV2 to GND if no ACFET2 and RBFET2 installed. |
ACDRV1 | 11 | P | Input FETs Driver Pin 1 – The charge pump output to drive the port #1 input N-channel MOSFET (ACFET1) and the reverse blocking N-channel MOSFET (RBFET1). The charger turns on the back-to-back MOSFETs by increasing the ACDRV1 voltage 5V above the common source connection of the ACFET1 and RBFET1 when the turn-on condition is met. Tie ACDRV1 to GND if no ACFET1 and RBFET1 installed. |
QON | 12 | DI | Ship FET Enable or System Power Reset Control Input – When the device is in ship mode or in the shutdown mode, the SDRV turns off the external ship FET to minimize the battery leakage current. A logic low on this pin with tSM_EXIT duration turns on ship FET to force the device to exit the ship mode. A logic low on this pin with tRST duration resets system power by turning off the ship FET for tRST_SFET (also setting the charger in HIZ mode when VBUS is high) and then turning on ship FET (also disabling the charger HIZ mode) to provide full system power reset. During tRST_SFET when the ship FET is off, the charger applies a 30mA discharging current on SYS to discharge system voltage. The pin contains an internal pull-up through a RQON resistor. The typical output voltage is 3.6 V-3.8 V with VBUS and VBAT > 5V. |
CE | 13 | DI | Active Low Charge Enable Pin – Battery charging is enabled when EN_CHG bit is 1 and CE pin is LOW. CE pin must be pulled HIGH or LOW, do not leave floating. |
SCL | 14 | DI | I2C Interface Clock – Connect SCL to the logic rail through a 10 kΩ resistor. |
SDA | 15 | DIO | I2C Interface Data – Connect SDA to the logic rail through a 10 kΩ resistor. |
TS | 16 | AI | Temperature Qualification Voltage Input – Connect a negative temperature coefficient thermistor. Program temperature window with a resistor divider from REGN to TS to GND. Charge suspends when TS pin voltage is out of range. Recommend a 103AT-2 10kΩ thermistor. |
ILIM_HIZ | 17 | AI | Input Current Limit Setting and HIZ Mode Control Pin – Program ILIM_HIZ voltage by connecting a resistor divider from pull up rail to ILIM_HIZ pin to ground. The pin voltage is calculated as: VILIM_HIZ = 1V + 800mΩ × IINDPM, in which IINDPM is the target input current. The input current limit used by the charger is the lower setting of ILIM_HIZ pin and the IINDPM register. When the pin voltage is below 0.75V, the buck-boost converter enters non-switching mode, similar to HiZ mode using EN_HIZ bit, but with REGN on. When the pin voltage is above 1V, the converter resumes switching. Connect ILIM_HIZ to REGN to set the maximum input current limit. |
BATP | 18 | P | Positive Input for Battery Voltage Sensing – Connect to the positive terminal of battery pack. Place 100Ω series resistance between this pin and the battery positive terminal. |
BTST2 | 19 | P | Output High Side Power MOSFET Gate Driver Power Supply – Connect a 10V or higher rating, 47nF ceramic capacitor between SW2 and BTST2 as the bootstrap capacitor for driving high side switching MOSFET (Q4). |
PROG | 20 | AI | Charger POR Default Settings Program – At power up, the charger detects the resistance tied to PROG pin to determine the default switching frequency and the default battery charging profile. The surface mount resistor with ±1% or ±2% tolerance is recommended. Please refer to more details in the section of PROG Pin Configuration. |
INT | 21 | DO | Open Drain Interrupt Output. – Connect the INT pin to a logic rail via a 10kΩ resistor. The INT pin sends an active low, 256μs pulse to the host to report the charger device status and faults. |
BAT | 22-23 | P | The Battery Charging Power Connection – Connect to the positive terminal of the battery pack. The internal charging current sensing circuit is connected between SYS and BAT. The recommended capacitors at BAT are 2 pieces of 10μF ceramic capacitors. |
SDRV | 24 | P | External N-channel Ship FET (SFET) Gate Driver Output – The driver pin of the external ship FET. The ship FET is always turned on when the ship mode is disabled, and it keeps off when the charger is in ship mode or shutdown mode. Connect a 1nF, 50V rated, 0402 package, ceramic capacitor from SDRV to GND or SDRV to BAT when the ship FET is not used. |
SYS | 25 | P | The Charger Output Voltage to System – The internal N-channel high side MOSFET (Q4) is connected between SYS and SW2 with drain on SYS and source on SW2. The recommended capacitors at SYS are 5 pieces of 10μF and one piece of 0.1μF ceramic capacitors. Place the 0.1μF ceramic capacitor as close as possible to the charger IC. |
SW2 | 26 | P | Boost Side Half Bridge Switching Node Inductor connection to mid point of Q3 and Q4 switches. |
GND | 27 | P | Ground Return |
SW1 | 28 | P | Buck Side Half Bridge Switching Node Inductor connection to mid point of Q1 and Q2 switches. |
PMID | 29 | P | Q1 MOSFET Drain Connection – An internal N-channel high side MOSFET (Q1) is connected between PMID and SW1 with drain on PMID and source on SW1. The recommended capacitors at PMID are 3 pieces of 10μF and one piece of 0.1μF ceramic capacitors. Place the 0.1μF ceramic capacitor as close as possible to the charger IC. If backup mode will be used, an additional 2 pieces of 33 uF POSCAP are recommended to hold up PMID during the switchover from adapter to battery backup. |