TIDT247 February   2022

 

  1.   Description
  2. 1Board Connections, Jumpers, and Test Points
  3. 2Pin Functions
  4. 3Quick Start Guide
  5. 4Testing and Results
    1. 4.1 Thermal Image
    2. 4.2 Control Loop
    3. 4.3 Efficiency - Output Voltage 8.5 V
  6. 5Waveforms

2 Pin Functions

Table 2-1 describes the pin functions of the individual connectors.

Table 2-1 Pin Functions
Connector Pin Description
J2 1 GND
2 I²C – SCL
3 I²C – SDA
4 Vpu – 3.3-V pullup voltage for open drain IOs and I²C interface
J4 1 10-kΩ resistor – connect to pin 2 if no external NTC is used
2 BQ25171-Q1 NTC connection
3 GND
J6 1 10-kΩ resistor – connect to pin 2 if no external NTC is used
2 BQ25171-Q1 NTC connection
3 GND
J5 2 BQ25171-Q1 Charge Enable. 10-k pulldown – pull high to disable charger
4 BQ34210-Q1 Alert output. 10-k pullup to Vpu
6 Learning load EN. FET input. 10-k pulldown – pullup to enable learning load
8 BQ25171-Q1 STAT2 output. 22-k pullup to Vpu
10 BQ25171-Q1 STAT1 output. 22-k pullup to Vpu
12 LM5152-Q1 enable. Pull high to enable boost converter
14 LM5152-Q1 status output. 22k pullup to Vpu
18 LM74800-Q1 enable input. Pull high to connect main power input to boost converter
20 Backup battery enable. 4.7-k pullup to Vpu. Pull low for normal operation, pull high or leave open with applied pullup voltage for backup battery operation
All others No connection
J7 All uneven GND
20 Connect to GND to disable charge timer
22 Connect to GND to set charge timer to 10 h
24 Connect to GND to set charge timer to 5 h
2 Connect to GND to set charging voltage to 3.5 V
4 Connect to GND to set charging voltage to 3.6 V
6 Connect to GND to set charging voltage to 3.7 V
8 Connect to GND to set charging voltage to 3.8 V
10 Connect to GND to set charging voltage to 3.9 V
12 Connect to GND to set charging voltage to 4.05 V
14 Connect to GND to set charging voltage to 4.1 V
16 Connect to GND to set charging voltage to 4.2 V
18 Connect to GND to set charging voltage to 4.35 V
J12 1 LM5152-Q1 internal VCC. For frequency response analysis, connect 5.5 V to this pin and pin 2 and populate R37 with 49.9 Ω. For normal operation, remove external voltage source and populate R37 with 0 Ω.
2 LM5152-Q1 MODE pin. Connect to pin 1 for FPWM operation, to pin 3 for Diode Emulation or leave open for skip mode
3 LM5152-Q1 AGND
J15 1 GND
2 Voltage sense output of resistive voltage divider. Divider can be disconnected by LM74800-Q1 to avoid leakage current.