Connector and support area

The connector area contains holes for three pin headers with 1x2, 1x5 and 2x12 pins, to give access to several signals and device pins as shown in tables below. Pin headers with 2.54mm spacing or wires can be soldered in here. A connector for in-circuit programming is surface mounted. Lastly the area contains a board ID system, which is described in more details in the next subsections.

Table 1. Signals that can be found on the 1x2 pin header holes
Name Description
PACK+(J1) Battery-pack positive input/output. Also connected to BATT pin
PACK-(J2) Battery-pack negative input/output (ground)
Table 2. Signals that can be found on the 1x5 pin header holes.
Name Description
CELL+/ PV4 (J3) Cells stack positive terminal. / Cell4 positive input
PV3 (J4) Cell3 positive input
PV2 (J5) Cell2 positive input
PV1 (J6) Cell1 positive input
CELL- / NV (J7) Cells stack negative terminal
Table 3. Signals that can be found on the 2x12 pin header holes.
Name Description
VREF (J32) Voltage reference positive pin
VREF Gnd (J33) Voltage reference ground pin
VFET (J21) VFET pin. Supply voltage to the device
VREG (J19) Voltage regulator output pin
Reset (J18) Reset pin
Ground (J20) Ground pin
PA3 (J31) Button switch input pin
PA2 (J30) Not used
PA1 (J29) External NTC 2 ADC input
PA0 (J28) External NTC 1 ADC input
PB7 (J17) SPI MISO pin
PB6 (J16) SPI MOSI pin
PB5 (J15) SPI SCK pin
PB4 (J14) LED 1 output pin
PB3 (J13) LED 2 output pin
PB2 (J12) LED 3 output pin
PB1 (J11) LED 4 output pin
PB0 (J10) LED 5 output pin
PC5 (J27) Not used
PC4 (J26) SMBus/TWI Clock pin
PC3 (J25) SMBus/TWI Data pin
PC2 (J24) 1-wire USART pin (not used)
PC1 (J23) Secondary protection blow input (not used)
PC0 (J22) External protection input pin

ISP via the SPI interface. Table 2-4 shows connections. Alternative pin names are also noted.

Table 4. ISP connector (J2) signals
Name Pin no. Description
MISO 1 Serial data out (PB7)
VCC 2 Supply voltage
SCK 3 Serial clock (PB5)
MOSI 4 Serial data in (PB6)
RESET 5 Reset signal (active low)
GND 6 Ground