Motorola Commercial Series Service Information page 25

Troubleshooting Table for Board and IC Signals
IC Designator
U251
VCO / Buffer
U310
5V Regulator
U320
3.3V Regulator
U330
3V Regulator
U401
Microprocessor
Pin Pin Function
12 Prescaler output
13 TX switch output (NU)
14 Vcc_BUFFERS
15 TX VCO emitter
16 TX VCO base
17 GND_LOGIC
18 Vcc_LOGIC
19 TRB input
20 FLIP input
1 Vin
2 Ground
3 Control input
4 Bypass capacitor
5 Vout
1 Ground
2 Feedback
3 Tap (NU)
4 Vin
5 Vout
6 Sense (NU)
7 Error (reset output)
8 Shutdown input
1 Vin
2 Ground
3 Control input
4 Bypass capacitor
5 Vout
1 PD4_SCK serial clock input
2 PD5_SS
3 PD6_VLIN
4 PG7_R_W
5 PG6_AS
6 PG0_XA13
7 PB7_ADDR15
8 PB6_ADDR14
9 PB3_ADDR11
DC Voltage Comments (Condition)
2.26
0.06
3.00
0 (RX mode)
0 (RX mode)
GND
3.00
0.03 From U201-2 (RX mode)
GND
7.48
GND
7.48
1.26
4.96
GND
1.23
0
7.48
3.23
0
3.20
7.48
7.48
GND
7.48
1.26
3.00
0
3.23 ASFIC chip select
3.23 EEPROM chip select
3.21
3.23
3.23
0.026
0.028
3.06
3-9