ICL7660S, ICL7660A

FN3179 Rev 7.01

Page 7 of 14

Feb 10, 2020

FIGURE 11. OUTPUT SOURCE RESISTANCE AS A FUNCTION OF OSCILLATOR FREQUENCY

NOTE:

14. These curves include, in the supply current, that current fed directly into the load RL from the V+ (see Figure 12). Thus, approximately half the

supply current goes directly to the positive side of the load, and the other half, through the ICL7660S and ICL7660A, goes to the negative side

of the load. Ideally, VOUT 2VIN, IS  2IL, so VIN x IS  VOUT x IL.

Typical Performance Curves

See Figure 12 on page 7, “ICL7660S Test Circuit”) and Figure 13 on page 7 “ICL7660A Test Circuit” (Continued)

400

300

200

100

0

100

1k

10k

100k

OSCILLATOR FREQUENCY (Hz)

V+ = 5V

TA = +25°C

I = 10mA

C1 = C2 = 10mF

C1 = C2 = 1mF

C1 = C2 = 100mF

1

2

3

4

8

7

6

5

+

-

C1

10µF

IS V+

(+5V)

IL

RL

-VOUT

C2

10µF

ICL7660S

V+

+

-

NOTE: For large values of COSC (>1000pF), the values of C1 and C2

should be increased to 100µF.

FIGURE 12. ICL7660S TEST CIRCUIT

NOTE: For large values of COSC (>1000pF) the values of C1 and C2

should be increased to 100µF.

FIGURE 13. ICL7660A TEST CIRCUIT

1

2

3

4

8

7

6

5

+

-

C1

10µF

IS V+

(+5V)

IL

RL

-VOUT

C2

10µF

ICL7660A

COSC

+

-

(NOTE)