the overvoltage value (for instance

∆V = 60V ±

4.2V).

Disable function

The zero current detector (ZCD) pin can be used

for device disabling as well. By grounding the

ZCD voltage the device is disabled reducing the

supply current consumption at 1.4mA typical (@

14.5V supply voltage).

Releasing the ZCD pin the internal start-up timer

will restart the device.

+Vo

D97IN591

-

+

2

R1

R2

Ccomp.

E/A

1

2.5V

∆I

-

+

X

PWM

DRIVER

2.25V

40

µA

∆I

Figure 2. Overvoltage Protection Circuit

40

µA

E/A OUTPUT

2.25V

DYNAMIC OVP

STATIC OVP

D97IN592A

OVER VOLTAGE

10

µA

Figure 1.

L6561

5/11