CM3842/3843

2001/06/27

Advanced

Champion Microelectronic Corporation

Page 6

APPLICATION INFORMATION

Fig. 1. Current Sense Circuit

Fig. 3. Oscillator Section

1.72

Fig. 2. Error Amplifier Configuration - the

amplifier can source or sink up to 0.5mA

Fig. 4. Open-loop laboratory test fixture: Careful grounding techniques are necessary for high peak

currents associated with capacitive loads. Timing and bypass capacitors should be connected to

GND pin in a single point ground. The transistor and 5K potentiometer are used to sample the

GND

COMP

Error

Amp

R

2R

1V

Current

Sense

Comparator

4.7K

1K

Error AMP

Adjust

4.7K

2N2222

100K

5K

Adjust

COMP

GND

Output

0.1

µµµµF

Output

1K,

1W

0.1

µµµµF

GND

2.5V

0.5mA

COMP

Error

Amp

GND