LA7995M Datasheet, PDF (2/5 Pages) Sanyo Semicon Device – Charge Pump Type DC-DC Converter

LA7995M
Operating Conditions at Ta = 25°C
Parameter
Recommended supply voltage
Operating supply voltage range
Symbol
V_CC
V_CCop
Conditions
Ratings
Unit
5
V
4.75 to 5.25
V
Operating Characteristics at Ta = 25°C
Parameter
Symbol
Conditions
Ratings
min
typ
max
Unit
Current drain
I_IN
I_O=1 mA, V_CC=5V
19
24
29 mA
Output voltage
V_OUT
I_O=1 mA, V_CC=5V
29
30.7
32
V
Output voltage fluctuation
˚V_OUT
I_O=1 mA, V_IN=4.75 to 5.25V
1.0
1.5
V
Output current
I_OUT
V_O=29V
1.5
1.7
mA
Oscillation frequency
f
C_OSC=150pF
35
50
65 KHz
Note: The above specifications are measured with external capacitance provided by three 0.33 µF chip capacitors(C1,
C2, C3).
Charge Pump Principle
Figure 1 shows a charge pump circuit. Driving S1 and S2 with opposite phase produces a doubled voltage
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In order to supply 30V from 5V, the LA7995M uses three charge pump circuits in series to produce a step-up factor of 2
x 2 x 2 = 8.
71598RM(KI) No. 5920-2/5