L6561
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.
OVER VOLTAGE
V
OUT nominal
I
SC
40µA
10µA
E/A OUTPUT
2.25V
DYNAMIC OVP
STATIC OVP
D97IN592A
Figure 5. Overvoltage Protection Circuit
Ccomp.
+Vo
R1
1
R2
-
+
2.5V
-
2.25V
∆I
+
E/A
∆I
2
X
PWM
DRIVER
40µA
D97IN591
5/13
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