TDA16846.pdf

The TDA 16846 is optimized to control free running or fixed frequency flyback converters
with or without Power Factor Correction (Current Pump). To provide low power
consumption at light loads, this device reduces the switching frequency continuously
with load, towards an adjustable minimum (e. g. 20 kHz in standby mode). Additionally,
the start up current is very low. To avoid switching stresses of the power devices, the
power transistor is always switched on at minimum voltage. A special circuit is
implemented to avoid jitter. The device has several protection functions: VCC over- and
undervoltage, mains undervoltage, current limiting and 2 free usable fault comparators.
Regulation can be done by using the internal error amplifier or an opto coupler feedback
(additional input). The output driver is ideally suited for driving a power MOSFET, but it
can also be used for a bipolar transistor. Fixed frequency and synchronized operation
are also possible.