Datasheet

Pin Functions
MC68HC908AP Family Data Sheet, Rev. 4
Freescale Semiconductor 25
1.5 Pin Functions
Description of the pin functions are provided in Table 1-2.
Table 1-2. Pin Functions
PIN NAME PIN DESCRIPTION IN/OUT
VOLTAGE
LEVEL
V
DD
Power supply.
In
4.5 to 5.5
or
2.7 to 3.3
V
SS
Power supply ground.
Out 0 V
V
DDA
Power supply for analog circuits.
In
V
DD
V
SSA
Power supply ground for analog circuits.
Out
V
SS
V
REFH
ADC input reference high.
In
V
DDA
V
REFL
ADC input reference low.
Out
V
SSA
V
REG
Internal (2.5V) regulator output.
Require external capacitors for decoupling.
Out
2.5V
(1)
RST
Reset input, active low; with internal pullup and schmitt
trigger input.
In
V
DD
IRQ1
External IRQ1 pin; with internal pullup and schmitt trigger
input.
In
V
DD
Used for mode entry selection.
In
V
DD
to V
TST
OSC1
Crystal or RC oscillator input.
In
V
REG
OSC2
Crystal OSC option: crystal oscillator output; inverted
OSC1.
Out
V
REG
RC OSC option: bus clock output.
Out
V
REG
Internal OSC option: bus clock output.
Out
V
REG
CGMXFC
CGM external filter capacitor connection.
In/Out Analog
PTA0/ADC0
:
PTA7/ADC7
8-bit general purpose I/O port.
In/Out
V
DD
Pins as ADC inputs, ADC0–ADC7.
In
V
REFH
Each pin has high current sink for LED.
Out
V
DD