Speedometer/Odometer or Tachometer Application
R3
R4
CP+
CP- 20
1
2
3
4
5
6
7
8
C4
C
T
R
T
Speedo
Input
+
SQOUT
FREQIN
F/VOUT
19
18
17
16
15
14
VREG
NC
R2
C3
BIAS
Gnd
Gnd
NC
Gnd
Gnd
NC
SIN+ 13
COS+
COS-
VCC
SINE-
FGEN
9
12
11
Battery
10
D1 R1
D2
C1
C2
COSINE
SINE
Speedometer
Air Core
Gauge
200W
Figure 6
R1 - 3.9, 500mW
R2 - 10k½
C4 - 0.47µF
C
T - 0.0033µF, +/- 30 PPM/¡C
R3 - 3k½
R4 - 1k½
D1 - 1A, 600 PIV
D2 - 50V, 500mW Zener
R
T - Trim Resistor +/- 20 PPM/DEG. C
C1 - 0.1µF
C2 - 1. Stand alone Speedo or Tach "0" µF
Note 1: For 58% Speed Input TMAX ² 5/fMAX where
TMAX = CT(R3+R4)
fMAX = maximum speed input frequency
2. Stand alone Speedo or Tach with return to Zero, 2000µF
3. With CS-8441 application, 10µF
C3 - 0.1µF
R3
C3
R4
CP+
CP- 20
1
2
3
4
5
6
7
8
C4
C
T
R
Speedo
Input
+
T
SQOUT
F/VOUT
19
18
17
16
15
14
VREG
NC
FREQIN
R2
BIAS
Gnd
Gnd
NC
Gnd
Gnd
NC
SIN+ 13
COS+
COS-
VCC
SINE-
FGEN
9
12
11
Battery
10
D1 R1
D2
C1
COSINE
SINE
Speedometer
Air Core
Gauge
200W
C2
1
CS8441
Air Core
Stepper Motor
200W
Odometer
Figure 7
Note 1: The product of CT and RT have a direct effect on
Note 4: The IC must be protected from transients above
60V and reverse battery conditions
Note 5: Additional filtering on the FREQIN lead may be
required
gain and therefore directly effect temperature
compensation
Note 2: C4 Range; 20pF to .2µF
Note 3: R4 Range; 100k½ to 500k½
7
CHERRY [ CHERRY SEMICONDUCTOR CORPORATION ]
