Motorola Pr400 Detailed 6881096c25 B Manual

6881096C25-BJune, 2005
VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals 6-7
6.4 Troubleshooting Table for Board and IC Signals
Table 6-4.  Troubleshooting Table for Board and IC Signals 
IC Designator Pin Pin Function DC Voltage Comments (Condition)
U51
IFIC1RF input 44.85 MHz1.20
2 RF input decoupling 1.20
32nd LO osc output4.02
4 2nd LO osc input 4.60
5RSSI output0.74(no received signal)
6 Vcc 4.70
7Audio feedback0.89
8 Audio output 1.44 DEMOD to stage U510
9RSSI...

June, 20056881096C25-B
6-8VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals
U110
RF Power Amp
1RF input0(TX mode)
2 Vgg (gate bias) 2.65 (typ) (TX mode) (4.25 V typ at VHF)
3Vdd 6.59(TX mode)
4 RF output -- Do not measure
5GroundGND
U150
Dual Opamp1 Unit 1 output 4.20 (typ) (TX mode) (5.8 V typ at VHF)
2Unit 1 (-) input2.39 (typ)(TX mode)
3 Unit 1 (+) input 2.39 (typ) (TX mode)
4GroundGND
5 Unit 2 (+) input 3.30 (typ) (TX mode)
6Unit 2 (-) input3.35 (typ)(TX mode)
7 Unit 2 output...

6881096C25-BJune, 2005
VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals 6-9
U201
Freq Synthesizer
24Ref osc XTAL20
25 Ref osc warp output 3.00
26Superfilter cap4.48
27 Superfilter base (NU) 3.76
28Superfilter output4.52
29 NC2 0
30Superfilter input4.96
31 NC3 0
32Prescaler input1.97
33 Prescaler ground GND
34Prescaler Vdd2.99
35 Prescaler Vref (NU) 1.97
36Digital Vdd2.99
37 TEST1 (NU) 0.01
38TEST2 (NU)0
39 Bias 2 3.38 (typ) (1.34 V in TX mode)
40Bias 11.50 (typ)(3.20 V in TX...

June, 20056881096C25-B
6-10VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals
U251
VCO / Buffer
12Prescaler output2.26
13 TX switch output (NU) 0.06
14Vcc_BUFFERS3.00
15 TX VCO emitter 0 (RX mode)
16TX VCO base0(RX mode)
17 GND_LOGIC GND
18Vcc_LOGIC3.00
19 TRB input 0.03 From U201-2 (RX mode)
20FLIP inputGND
U310
5 V Regulator1 Vin 7.48
2GroundGND
3 Control input 7.48
4Bypass capacitor1.26
5Vout 4.96
U320
3.3 V Regulator
1GroundGND
2 Feedback 1.23
3Tap (NU)0
4 Vin 7.48
5Vo u...

6881096C25-BJune, 2005
VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals 6-11
U401
Microprocessor
10PB1_ADDR93.05
11 PB2_ADDR10 0.16
12VDD3.23
13 VSS GND
14PBO_ADDR83.05
15 PB5_ADDR13 0.13
16PG1_XA140.20
17 PG4_XA17 3.17
18PG5_XA180
19 PG3_XA16 3.21
20PG2_XA150.30
21 PB4_ADDR12 0.22
22PF7_ADDR73.03
23 PF6_ADDR6 3.08
24PF5_ADDR53.06
25 PF4_ADDR4 0.16
26PF3_ADDR30.26
27 PF2_ADDR2 3.06
28PF1_ADDR13.06
29 PFO_ADDR0 3.05
30PC0_DATA00.69
31 PC1_DATA1 0.96
32PC2_DATA21.10
33 PC3_DATA3...

June, 20056881096C25-B
6-12VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals
U401
Microprocessor
46PH1_PW23.00
47 PH0_PW1 3.23 Synth chip select
48XIRQ3.00
49 PI7 1.48 RX enable
50PI60.01TX enable
51 PI5 3.23
52PI40Green LED enable
53 PI3 0 Red LED enable
54PI20
55 PI1 0
56PI02.98Lock detect from U201-4
57 MODB_VSTBY 3.22 Boot mode enable
58MODA_LIR3.12
59 AVDD 3.23
60PE7_AN73.20
61 PE6_AN6 3.20
62PE5_AN52.91VOX threshold detect
63 PE4_AN4 0.73 RSSI input
64PE3_AN30.14
65 PE2_AN2...

6881096C25-BJune, 2005
VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals 6-13
U401
Microprocessor
82PA3_IC4_OC5_OC13.00
83 PA4_OC4_OC1 0 Squelch detect input
84PA 5 _ O C 3 _ O C 10Channel activity input
85 PA6_OC2_OC1 0
86PA 7 _ PA 1 _ O C 10
87 VSSR GND
88VDDR3.23
89 ECLK (NU) 1.60
90EXTAL1.70Clock from U451-28
91 XTAL 1.40 Not used
92VDDSYN0
93 XFC (NU) 0
94RESET3.20From U320
95 LVOUT 0
96IRQ3.20
97 PD0_RXD 3.23
98PD1_TXD1.9
99 PD2_MISO 0
100PD3_MOSI3.23
U402
EEPROM1 Chip...

June, 20056881096C25-B
6-14VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals
U404
Flash ROM
10A163.17
11 A 1 5 0 . 3 0
12A120.22
13 A7 3.03
14A63.08
15 A5 3.06
16A40
17 A3 0.24
18A23.08
19 A1 3.05
20A03.05
21 D0 0.69
22D10.94
23 D2 1.08
24GNDGND
25 D3 0.78
26D40.59
27 D5 0.66
28D60.67
29 D7 0.75
30EN_CE3.01From U401-38
31 A10 0.16
32EN_OE0From U401-86
U451
ASFIC_CMP1 VDD for analog circuits 3.00
2DISC audio input1.34From U510
3 Ground for analog circuits GND
4DACU output0
5 DACR...

6881096C25-BJune, 2005
VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals 6-15
U451
ASFIC_CMP
14GCB1 general purpose output0
15 GCB0 general purpose output3.00 BW select (25 kHz mode)
16Squelch channel activity output0To U401-84
17 Squelch detect digital output 0 To U401-83
18PL/low speed data I/O1.50
19 High speed data I/O 3.00
20Chip select3.23From U401-2
21 Serial clock input 0
22Serial data input3.23
23 Ground for clock synthesizer GND
24Loop filter cap for clock syn0.74
25...

June, 20056881096C25-B
6-16VHF Troubleshooting Tables: Troubleshooting Table for Board and IC Signals
Notes:
U480
Dual Opamp1 Unit 1 output 2.48
2Unit 1 (-) input2.48
3 Unit 1 (+) input 2.46
4GroundGND
5 Unit 2 (+) input 0.28
6Unit 2 (-) input0.29
7 Unit 2 output 0
8Vcc4.96
U490
Audio Power Amp1 Enable/shutdown 0.12 (Unsquelched)
2Bias reference3.26(Unsquelched)
3 (+) input 3.26 (Unsquelched)
4(-) input3.27(Unsquelched)
5 (-) output 3.25 (Unsquelched)
6Vcc7.48(Unsquelched)
7Ground GND
8(+)...