Fairchild AN-7511 - Manual (Page 3)

©2002 Fairchild Semiconductor Corporation Application Note 7511 Rev. A1
FIGURE 5A. YIELDING 4-kV ISOLATION, A PIEZOELECTRIC COUPLER PROVIDES TRANSFORMER-LIKE PERFORMANCE AND AN
ISOLATED POWER SUPPLY.
FIGURE 5B. THIS CIRCUIT PROVIDES THE DRIVE FOR THIS ARTICLE’S MOTOR-CONTROL CIRCUIT.
CONTROL
INPUT
ON
OFF
GFOE1A1
EMITTER
(DISCONNECTED)
DETECTOR
(CONNECTED)
10M (30FT)
QSF2000C
(W/CONNECTORS)
GFOD1A1
1N914
R
1
2N5354
C
Q
1
R
2
R
3
IGT
+
-
FIGURE 4. ELIMINATE EMI IN HIGH-FLUX OR NOISE ENVI-
RONMENTS BY USING FIBER-OPTIC COMPO-
NENTS. THESE PARTS ALSO ALLEVIATE
PROBLEMS ARISING FROM CAPACITIVE COU-
PLING IN ISOLATION ELEMENTS.
Piezos Pare Prices
OUTPUT
VOLTAGE
ACOUSTIC WAVE
OSCILLATOR
IGT
4.7k
1N914
1N914
PZ61343
D33D21
18V
2.5k
3.3k
2.7k
0.001
µ F
0.001
µ F
1k
NE555
Application Note 7511