ZHCSCT5A September 2014 – January 2017 TPS54561-Q1
PRODUCTION DATA.
PIN | I/O | DESCRIPTION | ||
---|---|---|---|---|
NAME | NO. | |||
BOOT | 1 | O | The device requires a bootstrap capacitor between BOOT and SW. If the voltage on this capacitor is below the minimum required voltage to operate the high-side MOSFET, the gate driver switches off until the bootstrap capacitor recharges. | |
COMP | 7 | O | Error amplifier output, and input to the output switch-current comparator (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 Adjust Undervoltage Lockout section. | |
FB | 6 | I | Inverting input of the transconductance (gm) error amplifier. | |
GND | 8 | — | Ground | |
PWRGD | 10 | O | Power-good is an open-drain output that asserts if the output voltage is low because of thermal shutdown, dropout, overvoltage, or EN shutdown. | |
RT/CLK | 5 | 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. When pulled above the PLL upper threshold, a mode change occurs, and the pin becomes a synchronization input. This change disables the internal amplifier, and the pin is a high-impedance clock input to the internal PLL. Stopping the clocking edges re-enables the internal amplifier, and the operating mode returns to resistor programmed mode. | |
SS/TR | 4 | I | Soft-start and tracking input pin. An external capacitor connected to this pin sets the output rise time. A voltage on this pin overrides the internal reference, which allows use of the pin for tracking and sequencing. | |
SW | 9 | I | The source of the internal high-side power MOSFET, and switching node of the converter. | |
VDD | 2 | I | Input supply pin with 4.5-V to 60-V operating range. | |
Thermal pad | — | — | To ensure proper operation, electrically connect the GND pin to the copper pad under the IC on the printed circuit board. |