User's Guide

11
GPIOs
16 pins connector"
Pins
Name
Type
Description
1
Ground
P
Ground reference for logic and I/O pins
2
PPR
O
Power present state&
0V when power present at CHG_IN [open drain]
3
Ground
P
Ground reference for logic and I/O pins
4
TX2
I/O"
O
I/O pin (0-3.3V)"
UART TX (0-3.3V)
5
BAT+
P
Positive supply (3.4 to 5.5Vdc)
6
RX2
I/O"
I
I/O pin (0-3.3V)"
UART RX (0-3.3V)
7
TX
I/O"
O"
I/O
I/O pin (0-3.3V)"
UART TX (0-3.3V)"
I2C SDA pin
8
AN1
I/O "
I
I/O pin (0-3.3V)"
Analog input (0-3.3V)
9
AN2
I/O"
I
I/O pin (0-3.3V)"
Analog input (0-3.3V)
10
RX
I/O"
I"
I/O
I/O pin (0-3.3V)"
UART RX (0-3.3V)"
I2C SCL pin
11
SDI
I
SPI data input
12
PWM2
I/O
I/O pin (0-3.3V)
13
CHG_IN
P
LI-ION or LI-Po battery charger input power (4.2-10Vdc)
14
SDO
O
SPI serial data output
15
3.3V
P
3.3V DC output (max 200mA)
16
SCK
O
SPI serial data clock