VOLTAGE-TO-FREQUENCY/
FREQUENCY-TO-VOLTAGECONVERTERS
1
2
3
4
5
6
7
8
TC9400
TC9401
TC9402
+
V
= 8V TO 15V (FIXED)
R
2
14
10kΩ
V
2
0.9
2
6
5V
R
1
8
f
OUT
0.01
µF
8.2
kΩ
GAIN
ADJUST
10kΩ
7
10
f
/2
V
2
kΩ
OUT
REF
11
0.01
µF
OFFSET
ADJUST
0.2
TC9400
12
5
R
1
R
820
pF
IN
180
pF
1MΩ
3
I
V
IN
IN
0V–10V
I
1
4
9
IN
100 kΩ
+
1
R
R
2
V
1
f
= I
×
OUT IN
–
10V
12V 1.4 MΩ 14kΩ
15V 2 MΩ 20kΩ
1 MΩ 10kΩ
(V V ) (C
)
2
7
REF
+
(V –V )
IN
(V –V )
2
2
+
=
I
IN
R
(0.9 R +0.2 R )
1 1
IN
Figure 4 . Fixed Voltage — Single Supply Operation
+12 to +15V
1.2k*
14
V
DD
1µF
11 THRESHOLD
DETECT
R1
910k
R4
100k
C
INT
12
10k
10k
AMP OUT
D2
5.1VZ
C
5
C
REF
REF
R3
GAIN
TC9400
3
2
6
I
8
IN
ZERO
f
OUT
ADJUST
100k
10
9
OUTPUT
FREQUENCY
GND
f
/2
OUT
R2
910k
R5
91k
D1
5.1VZ
0.1µ
OUTPUT
COMMON
7
1
V
I
REF
Rp
OFFSET
20k
INPUT
VOLTAGE
(0 to 10V)
BIAS
100k
V
SS
4
DIGITAL
GROUND
ANALOG GROUND
COMPONENT SELECTION
F/S FREQ.
1 kHz
CREF
2200pF 4700pF
CINT
10 kHz
100 kHz
180pF
27pF
470pF
75pF
Figure 5. Voltage to Frequency
TELCOM SEMICONDUCTOR, INC.
3-295
TELCOM [ TELCOM SEMICONDUCTOR, INC ]
