ZHCSQK6 May 2022 TPS92643-Q1
PRODUCTION DATA
TI recommends a simple integral compensator to achieve stable operation across the wide operating range. The buck converter behaves as a single pole system with additional phase lag caused by the switching behavior. The gain and phase margin are, consequently determined by the choice of the switching frequency and are independent of other design parameters. TI recommends a 1-nF to 10-nF capacitor to achieve bandwidth between 4 kHz and 40 kHz. The choice of compensation capacitor impacts the transient response and PWM dimming performance. TI recommends a larger compensation capacitor (lower bandwidth) to limit the LED current overshoot on the rising edge of internal or external PWM signal.
BANDWIDTH (kHz) | BOOTSTRAP CAPACITOR (nF) |
---|---|
40 | 1 |
18 | 2.2 |
12 | 3.3 |
8.5 | 4.7 |
5.8 | 6.8 |
4.8 | 8.2 |
4 | 10 |