ZHCSG12 February 2017 TPS54540B-Q1
PRODUCTION DATA.
PIN | I/O | DESCRIPTION | ||
---|---|---|---|---|
NAME | NO. | |||
BOOT | 1 | I | A bootstrap capacitor is required between BOOT and SW. If the voltage on this capacitor is below the minimum required to operate the high side MOSFET, the MOSFET stops switching until the capacitor is refreshed. | |
COMP | 6 | I | Error amplifier output and input to the output switch current (PWM) comparator. Connect frequency compensation components to this pin. | |
EN | 3 | I | Enable pin, with internal pullup current source. Pull below 1.2 V to disable. Float to enable. Adjust the input undervoltage lockout with two resistors. See the Enable and Adjusting Undervoltage Lockout section. | |
FB | 5 | I | Inverting input of the transconductance (gm) error amplifier. | |
GND | 7 | — | Ground | |
RT/CLK | 4 | I | Resistor Timing and External Clock. An internal amplifier holds this pin at a fixed voltage when using an external resistor to ground to set the switching frequency. If the pin is pulled above the PLL upper threshold, a mode change occurs and the pin becomes a synchronization input. The internal amplifier is disabled and the pin is a high impedance clock input to the internal PLL. If clocking edges stop, the internal amplifier is reenabled and the operating mode returns to resistor frequency programming. | |
SW | 8 | O | The source of the internal high-side power MOSFET and switching node of the converter. | |
VIN | 2 | I | Input supply voltage is connected to this pin with a 4.5-V to 42-V operating range. | |
PowerPAD | 9 | — | GND pin must be electrically connected to the exposed pad on the printed-circuit-board for proper operation. |