HSMC3842 Hi-Sincerity Mocroelectronics, HSMC3842 Datasheet - Page 6

• Manufacturer Part Number: HSMC3842
• Description: HIGH PERFORMANCE CURRENT MODE CONTROLERS
• Manufacturer: Hi-Sincerity Mocroelectronics

Application Information
High peak currents associated with capacitive loads necessitate careful grounding techniques. Timing and
bypass capacitors should be connected close to pin5 in a single point ground. The transistor and 5KΩ
potentiometerare used to samplethe oscillator waveform and apply an adjustable ramp to pin3.
H3842P
Open Loop Test Circuit
Oscillator and Output Waveforms
Error Amp Configuration
CT
Zi
RT
Error Amp.
Adjust
8
4
Zf
4.7KΩ
1KΩ
4.7KΩ
PWM
HI-SINCERITY
MICROELECTRONICS CORP.
Id
COMP
100KΩ
V
HPN2222A
FB
Clock
Oscillator
I
Adjust
1
2
SENSE
2.5V
5V REG
1
2
5
Vcc
+
-
7
GND
5KΩ
RT
3
COMP
RT/CT
I
SENSE
V
FB
6
1mA
1
2
3
4
Output
V
REF
H3842
CT
8
Under Voltage Lockout
Vi
7
6
5
7
Output
Output
Vcc
Output
Ground
CT
CT
ON/OFF Command
To Rest Of IC
Von
Voff
0.1uF
0.1uF
H3842
16V
10V
Large RT / Small CT
Small RT / Large CT
1W
1KΩ
A
<0.5mA
<17mA
Spec. No. : HP200202
Issued Date : 1998.08.01
Revised Date : 2002.12.03
Page No. : 6/10
HSMC Product Specification
Icc
Output
Ground
Vref
Vcc
Voff Von
Vcc