71598RM(KI) No. 5920-3/5

Block Diagram

The LA7995M incorporates the following functions for controlling the 3-stage charge pump circuit:

• Oscillator

• Switching circuit

Figure 2 Block diagram

1

2

3

4

5

6

7

＋

＋

＋

8

9

10

11

12

13

14

0.33μF

0.33μF

0.33μF

4.7μF

4.7μF

150pF

47μF

0.01μF

VCC=5V

Vout=30V

NC

NC

NC

A11011

Discharge：200μA

Charge：6μA

6μA

100μA

200μA

1kΩ

1kΩ

VCC

200Ω

7.5kΩ

1kΩ

Equivalent Internal Circuit and Recommended Peripheral Circuitry

1

2

3

4

5

6

7

＋

＋

＋

8

9

10

11

12

13

14

C1

D1

C2

C3

Creg

Cout

Cosc

Cvcc1

Cvcc2

VCC=5V

NC

NC

NC

Charge pump

1

Charge pump

2

Charge pump

3

Oscillator

Switching

circuit

30V zener

diode circuit

A11010

LA7995M