Philips Semiconductors
Zero-voltage-switching
resonant converter controller
Product speciļ¬cation
TEA1610P; TEA1610T
FUNCTIONAL DESCRIPTION
Start-up
When the applied voltage at VDD reaches VDD(initial) (see
Fig.5), the low side power switch is turned-on while the
high side power switch remains in the non-conducting
state. This start-up output state guarantees the initial
charging of the bootstrap capacitor (Cboot) used for the
floating supply of the high side driver.
During start-up, the voltage on the frequency capacitor (Cf)
is zero and defines the start-up state. The output voltage
of the error amplifier is kept constant (typ. 2.5 V) and
switching starts at about 80% of the maximum frequency
at the moment pin VDD reaches the start level.
The start-up state is maintained until VDD reaches the start
level (13.5 V), the oscillator is activated and the converter
starts operating.
handbook, full pagewidth
VDD
0
GH - SH
0
GL
0
VDD(start)
VDD(initial)
Fig.5 Start-up.
t
MGT998
2001 Apr 25
5