FAN2110 Datasheet, PDF (13/17 Pages) Fairchild Semiconductor – TinyBuck™, 3-24V Input, 10A, High-Efficiency, Integrated Synchronous Buck Regulator

Over-Temperature Protection (OTP)
The chip incorporates an over-temperature protection
circuit that sets the fault latch when a die temperature of
about 150°C is reached. The IC restarts when the die
temperature falls below 125°C.
Auto-Restart
After a fault, EN pin is discharged by a 1µA current sink
to a 1.1V threshold before the internal 800KΩ pull-up is
restored. A new soft-start cycle begins when EN
charges above 1.35V.
Depending on the external circuit, the FAN2110 can be
configured to remain latched-off or to automatically
restart after a fault.
If auto-restart is not desired, tie the EN pin to the VCC
pin or pull it HIGH after VCC comes up with a logic gate
to keep the 1µA current sink from discharging EN to
1.1V. Figure 32 shows one method to pull up EN to VCC
for a latch configuration.
Table 1. Fault / Restart Configurations
EN Pin
Controller / Restart State
Pull to GND
OFF (Disabled)
Pull-up to VCC with 100K
No Restart – Latched OFF
(After VCC Comes Up)
Open
Immediate Restart After Fault
Cap. to GND
New Soft-Start Cycle After:
tDELAY (ms)=3.9 • C(nf)
When EN is left open, restart is immediate.
Figure 32. Enable Control with Latch Option
Power-Good (PGOOD) Signal
PGOOD is an open-drain output that asserts LOW
when VOUT is out of regulation, as measured at the FB
pin. Thresholds are specified in the Electrical
Specifications section. PGOOD does not assert HIGH
until the fault latch is enabled (T1.0) (see Figure 31).
© 2008 Fairchild Semiconductor Corporation
FAN2110 • Rev. 1.0.2
13
www.fairchildsemi.com