HA16150T Datasheet, PDF (12/25 Pages) Renesas Technology Corp – High-Speed Current Mode Push-Pull PWM Control IC

HA16150T/P
Functional Description
1. UVL Circuit
The UVL circuit monitors the Vcc voltage and halts operation of the IC in the event of a low voltage.
The voltage for detecting Vcc has a hysteresis characteristic, with 9.3 V as the start threshold and 8.3 V as the shutdown
threshold.
When the IC has been halted by the UVL circuit, control is performed to fix driver circuit output low, halt VREF output
and the oscillator, and reset the soft start circuit.
VCC
9.3V
8.3V
VREF
V_CT
4.5V
3V
2V
4.5V
V_SS
OUT1
OUT2
Figure 1
2. Remote ON/OFF Circuit
A remote on/off control function is incorporated, enabling the IC to be halted without cutting the supply voltage by
pulling the REMOTE pin up to 3.0 V or higher.
This function halts VREF output and driver output.
At this time the IC enters Remote-OFF mode and IC current dissipation can be decreased. This function can thus be
used for power management, etc.
When remote off control is performed, the soft start circuit is also reset, and therefore a soft start is effected when
restarting, preventing overshoot.
However, when restarting by the remote on control function before the SS pin is completely discharged, soft start
operation may not be performed normally. In such a case, add a circuit to pull the SS pin out in conjunction with a
remote off signal.
SS
REMOTE
100kΩ
Figure 2 Example of Circuit to Pull out SS Pin
Rev.3.00 Jan 30, 2007 page 12 of 24