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dently from the average output voltage. The precision in setting the overvoltage threshold is 7% of the ov-

ervoltage value (for instance

∆V = 60V ± 4.2V).

3.1 Disable function

The zero current detector (ZCD) pin can be used for device disabling as well. By grounding the ZCD volt-

age the device is disabled reducing the supply current consumption at 1.4mA typical (@ 14.5V supply volt-

age).

Releasing the ZCD pin the internal start-up timer will restart the device.

Figure 4.

Figure 5. Overvoltage Protection Circuit

40

µA

E/A OUTPUT

2.25V

DYNAMIC OVP

STATIC OVP

D97IN592A

OVER VOLTAGE

10

µA

+Vo

D97IN591

-

+

2

R1

R2

Ccomp.

E/A

1

2.5V

∆I

-

+

X

PWM

DRIVER

2.25V

40

µA

∆I