JAJSOD0A April 2022 – July 2022 TPS22811
PRODUCTION DATA
For all applications, TI recommends a ceramic decoupling capacitor of 0.1 μF or greater between the IN terminal and GND terminal.
The optimal placement of the decoupling capacitor is closest to the IN and GND terminals of the device. Care must be taken to minimize the loop area formed by the bypass-capacitor connection, the IN terminal, and the GND terminal of the IC.
High current-carrying power-path connections must be as short as possible and must be sized to carry at least twice the full-load current.
The GND terminal must be tied to the PCB ground plane at the terminal of the IC with the shortest possible trace. The PCB ground must be a copper plane or island on the board. TI recommends to have a separate ground plane island for the eFuse. This plane does not carry any high currents and serves as a quiet ground reference for all the critical analog signals of the eFuse. The device ground plane must be connected to the system power ground plane using a star connection.
The IN and OUT pins are used for heat dissipation. Connect to as much copper area on top and bottom PCB layers using as possible with thermal vias. The vias under the device also help to minimize the voltage gradient across the IN and OUT pads and distribute current uniformly through the device, which is essential to achieve the best on-resistance and current sense accuracy.
Locate the following support components close to their connection pins:
RIMON
CdVdT
Resistors for the EN/UVLO, EN/OVLO pins
Connect the other end of the component to the GND pin of the device with shortest trace length. The trace routing for the RIMON and CdVdt components to the device must be as short as possible to reduce parasitic effects on the current monitor and soft start timing. These traces must not have any coupling to switching signals on the board.
Protection devices such as TVS, snubbers, capacitors, or diodes must be placed physically close to the device they are intended to protect. These protection devices must be routed with short traces to reduce inductance. For example, TI recommends a protection Schottky diode to address negative transients due to switching of inductive loads. TI also recommends to add a ceramic decoupling capacitor of 1 μF or greater between OUT and GND. These components must be physically close to the OUT pins. Care must be taken to minimize the loop area formed by the Schottky diode/bypass-capacitor connection, the OUT pin and the GND terminal of the IC.