HA16150T Datasheet, PDF (18/25 Pages) Renesas Technology Corp – High-Speed Current Mode Push-Pull PWM Control IC

HA16150T/P
9. Usage on Half-bridge Power Supply
The HA16150 is operated in the current mode. However, the half-bridge power supply becomes unstable in principle
by using current mode control. The HA16150, therefore, cannot be used basically. In order to use the HA16150 with
the half-bridge power supply, add a circuit as shown below and operate the HA16150 in the voltage mode.
OUT1
R1
C1
Q1 OUT2
R2
C2
VREF
Q2
CS input filter
Vslope
R3
Dead Band Time
OUT1
1/fosc
OUT2
CS
(CSLIM – 2VF)
3
Figure 10 Example of Circuit for Voltage Mode Operation
Design the charging circuits for R1 (R2), C1 (C2), Q1 (Q2) and R3 so that the peak voltage of CS is lower than
(CSLIM-2VF)/3 at the maximum ON pulse width of OUT1 and OUT2.
Furthermore, set the input filter values between R3 and CS pin so that the CS voltage is discharged assuredly while both
of the OUT1 and OUT2 are at low level.
Rev.3.00 Jan 30, 2007 page 18 of 24