User's Manual

68P81093C75-A 11-5
Figure 18. PDR 3500 Schematic—Part I (Sheet 2 of 2)
DNP
DNP
DNP
DNP
DNP
DNP
LN+5
1%
10K
R48
1%
5.62K
R10
20K
R89
LN+5
MC74HC132AD
U16
4
5
6
C37
470pF
470pF
LN+5
LN+5
0.1uF
C90
X3
11
Y
3
Y0
1
Y1
5
Y2
2
Y3
4
C89
ENABLE*
6
GND
8
16
VCCVEE
7
X
13
X0
12
X1
14
X2
15
0
U1
MC74HC4052
8
A
10
B
9
100pF
R58
C19
20K
R65
R53
20K
20K
R29
R28
1K
X3
11
Y
3
Y0
1
5
Y1
Y2
2
Y3
4
6
ENABLE* GND
8
16
VCC
7
VEE
X
13
X0
12
X1
14
X2
15
U1
MC74HC4052
1
A
10
B
9
C35
C66
470pF
100pF 100pF
C65
L3
C43
0.22uF
220nH
16.2K
R37
1%
LN+5
LN+5
C70
100pF
100pF
C71
100pF
C72
1%
R34
27.4K
C91
470pF
220nH
L7
220nH
L6
L5
L4
220nH
100pF
220nH
LN+5
C23
C80
100pF
0.1uF
C34
0
R27
20K
R25
1%
MC33074
U3
13
12
14
C64
0.22uF10K
R47
1%
R36
10K
18.2K
R19
1%
470pF
C93C92
470pF
470pF
C94
220nH
L11
0
20K
R30
R26
C62
470pF
470pF
LN+5
C61
470pF
C44
470pF
C36
R20
10K
1%
R22
10.5K
1%
A+
0.1uF
C14
C17
100pF
4
Y3
12
X0
14
X1
15
X2
11
X3
3
Y
1
Y0
5
Y1
2
Y2
10
A
9
B
ENABLE*
6 8
GND
VCC
167
VEE
13
X
LN+5
U2
MC74HC4052
X3
11
Y
3
Y0
1
Y1
5
Y2
2
Y3
4
ENABLE*
6
GND
8
16
VCCVEE
7
X
13
X0
12
X1
14
X2
15
C18
U1
MC74HC4052
A
10
B
9
1%
100pF
10.5K
R49
16.2K
R21
1%
C47C46
470pF
3
Y
1
Y0
5
Y1
2
Y2
4
Y3
0.1uF
8
GND
VCC
167
VEE
13
X
12
X0
14
X1
15
X2
11
X3
U1
MC74HC4052
3
10
A
9
B
6
ENABLE*
100pF
C16
MC33074
U3
6
5
7
LN+5
LN+5
C79
0.1uF
14
X1
15
X2
11
X3
3
Y
1
Y0
Y1
5
2
Y2
4
Y3
10
A
9
B
ENABLE*
6 8
GND
VCC
16
VEE
7
13
X
12
X0
100pF
C24
U1
MC74HC4052
7
C63
100pF
470pF
C88
MC33074
U3
9
10
8
L10
220nH
1%
1%
R46
10K
R90
15K
33.2K
R24
1uF
C107
C86
470pF
470pF
C87
470pF
C22
470pF
C15
0.1uF
C21
R69
15K
470pF
LN+5
C84
100pF
C40
1%
R75
10K
LN+5LN+5LN+5
LN+5
R92
20K
R93
1K
R91
1.5K
LN+5
R76
L12
220nH
C78
27.4K
1%
LN+5
470pF
2.7K
R67
LN+5
2.2K
R66
1%
R35
16.2K
R13
5.62K
1%
LN+5
1%
R12
16.2K
LN+5LN+5
100pF
C81
1%
R11
32.4K
R54 R55
20K
U16
MC74HC132AD
1
2
3
20K
C108
22.1K
R97
2
3
1
100pF MC33074
U3
C25
470pF
R73R71
1.5K
R72
1.5K
15K
R70
15K
LN+5
220nH
L9
LN+5
L8
220nH
18K
R68
1%
R95
18.2K
LN+5
R94
1%
20K
PTT_SWITCH
1%
R96
33.2K
PTT_REQ_INV
PATEMP
VFINALFORWARD
Y2MUX
X2MUX
Y3MUX
X3MUX
BMUXCTRL
AMUXCTRL
SW3
SW2
SW1
SW3INV
VTEMP_FROM_PA
SW3INV
SW1
SW2
SW3
PTT_REQ_SC
PTT_REQ_EX
12
11
8
VFWD_XLATED
These op-amps are part of the forward voltage
translation. They subtract 0.6V from the forward
voltage and serve as buffers.
PA Identification. U11 and U17 select the PA ID
resistors read by the Exciter to determine the
frequency band of the PA and the backplane DIP
switch settings. Do-not-place resistors are
included for possible future use and should not be
placed in normal applications.
Temperature Voltage Translation: U13, U18, U3,
and peripheral circuitry translate the Temperature
Voltage (V
temp
) from the PA to the Exciter. The
appropriate translation circuit is selected by the
positions of switches 1, 2, and 3 of S1. The
equations implemented are as follows:
R98 prevents the op-amp U15 pin 8 from railing
high when not in use and impairing the proper
function of U12.
Temperature Voltage Translation Equations
Range DIP Settings Equation
VHF R1 & R2 000x/100x V
o
= -0.55 • V
i
+ 3.05
UHF R1 & R2 010x/110x V
o
= -V
i
+ 5.12
UHF R3 & R4 001x/101x V
o
= -1.69 • V
i
+ 8.32
800 MHz 011x V
o
= -0.67 • V
i
+ 3.97
10
11
12
13