MC68HC68 MOTOROLA [Motorola, Inc], MC68HC68 Datasheet - Page 22

• Manufacturer Part Number: MC68HC68
• Description: Real-Time Clock plus RAM with Serial Interface
• Manufacturer: MOTOROLA [Motorola, Inc]

MC68HC68T1
22
NOTES:
12 V
1. The V SYS and Line inputs can be used to sense the ignition turning on and off. An external switch is included to activate the
2. If an MC68HC11 MCU is used, delete the capacitor at the RESET pin.
3. Voltage at pin must not exceed absolute maximum V in specification.
+
–
system without turning on the ignition. Also, the CMOS CPU is not powered down with the system V DD , but is held in a low
power reset mode during power–down. When restoring power, the MC68HC68T1 enables the CLKOUT pin and sets the
PSE and CPUR pins high.
0.1
100 k
m
REG
F
5 V
W
NOTE 1
BUTTON
CLOCK
IGNITION
13
10
14
15
11
V BATT
POR
XTAL
2 MHz
LINE
MC68HC68T1
8
V SS
V DD
Figure 21. Automotive System
CLKOUT
16
CPUR
V SYS
PSE
INT
SPI
SS
12
9
2
1
3
7
3
NOTE 2
ENABLED POWER
39
27
1
2
RESET
OSC 1
IRQ
SPI
PORT
MC68HC05C4
40
20
V DD
V SS
PORT
MOTOROLA
28