ISL6742 Datasheet, PDF (17/18 Pages) Intersil Corporation – Advanced Double-Ended PWM Controller

ISL6742
Fault Conditions
A fault condition occurs if VREF or VDD fall below their
undervoltage lockout (UVLO) thresholds or if the thermal
protection is triggered. When a fault is detected, the soft-start
capacitor is quickly discharged, and the outputs are disabled
low. When the fault condition clears and the soft-start voltage
is below the reset threshold, a soft-start cycle begins.
An overcurrent condition is not considered a fault and does
not result in a shutdown.
Thermal Protection
Internal die over temperature protection is provided. An
integrated temperature sensor protects the device should
the junction temperature exceed +140°C. There is
approximately +15°C of hysteresis.
Ground Plane Requirements
Careful layout is essential for satisfactory operation of the
device. A good ground plane must be employed. VDD and
VREF should be bypassed directly to GND with good high
frequency capacitance.
References
[1] Ridley, R., “A New Continuous-Time Model for Current
Mode Control”, IEEE Transactions on Power
Electronics, Vol. 6, No. 2, April 1991.
17
FN9183.2
October 31, 2008