User Guide
19 of 46
Rev. 1.0
2022-03-09
48V Battery Switch Reference Design
R 48V BATT Switch10
System and functional description
Table 6
Button functionality
Button
Function
Description
RESET
Reset
Microcontroller reset
BUTTON2
Safestate
Pull SAFESTATEN pin low to initiate the 2ED4820-EM safe state
BUTTON1
ON/OFF
Switch on or off, including initialisation and precharge
If failure occurred (error LED on): clear failure flag
Switching on
When the switch is off and button 1 is pressed, the driver is enabled and initialized with the configuration
settings. Then the precharge path (channel B) is switched on for the configured precharge time to charge up the
load capacitor. When the precharge time is expired, the power switch (channel A) is activated and the
precharge path is switched off.
The status of the 2ED4820-EM outputs channel A (power switch) and channel B (precharge path) is displayed by
the respective status LEDs on the adaptor board. LED1 next to button 1 on the XMC Relax Lite Kit shows the
status of channel A.
Switching off
When the switch is on and button 1 is pressed, both channels are switched off and the driver is disabled.
Clearing failures
In case of a failure the error LED will light up. The failure flag can be cleared by pressing button 1.
Safestate
Pressing button 2 will initiate the safe state functionality of the gate driver 2ED4820-EM. Safe state is indicated
by LED2 next to this button.
Figure 20
Location of Status LEDs
