A1 |
GND |
Ground |
Ground |
A2 |
IN |
Power |
Input voltage connection. Connect IN to the input supply and bypass to GND with a 10-µF or larger ceramic capacitor. |
A3 |
SDA |
I/O |
Serial data input/output in the I2C Mode on LM3644. |
B1 |
SW |
Power |
Drain Connection for Internal NMOS and Synchronous PMOS Switches. |
B2 |
STROBE |
I/O |
Active high hardware flash enable. Drive STROBE high to turn on Flash pulse. Internal pulldown resistor of 300 kΩ between STROBE and GND. |
B3 |
SCL |
I/O |
Serial clock input for LM3644. |
C1 |
OUT |
Power |
Step-up DC-DC converter output. Connect a 10-µF ceramic capacitor between this pin and GND. |
C2 |
HWEN |
I/O |
Active high enable pin. High = Standby, Low = Shutdown/Reset. Internal pulldown resistor of 300 kΩ between HWEN and GND. |
C3 |
TORCH/TEMP |
I/O |
Torch terminal input or threshold detector for NTC temperature sensing and current scale back. |
D1 |
LED2 |
Power |
High-side current source output for flash LED. |
D2 |
TX |
I/O |
Configurable dual polarity power amplifier synchronization input. Internal pulldown resistor of 300 kΩ between TX and GND. |
D3 |
LED1 |
Power |
High-side current source output for flash LED. |