SLVSAF1E October 2010 – May 2019 TPS54388-Q1
The TPS54388-Q1 device uses an adjustable fixed-frequency, peak-current-mode control. An error amplifier, which drives the COMP pin, compares the output voltage through external resistors on the VSENSE pin to an internal voltage reference. An internal oscillator initiates the turnon of the high-side power switch. The device compares the error-amplifier output to the high-side power-switch current. When the sensed voltage derived from the power-switch current reaches the COMP voltage level, the high-side power switch turns off and the low-side power switch turns on. The COMP pin voltage increases and decreases as the output current increases and decreases. The device implements a current limit by clamping the COMP pin voltage to a maximum level, and also implements a minimum clamp for improved transient-response performance.