Other Parts Discussed in Thread: TIDA-01457
Hello,
I'm trying to figure out the PSM/PWM crossover frequency of the TPS82140 when used in an inverting buck/boost configuration similar to TIDA-01457.
My design parameters are: VIN = 3.3V (fixed), VOUT = -6V. Using equations 2/3 from TIDA-01457, I calculated a duty cycle of 64.5% and a inductor ripple current of ~1.06A. Per page 8 of the TPS82140 datasheet, the device enters PSM mode when the output current is equal to half of the inductor ripple current; which in this case is ~500mA.
This seems to line up with figure 14 in TIDA-01457; however, I'd like a second opinion on this.
Don