SLUUC72A September 2020 – October 2021 TPS542A50
To enter programming mode, the SYNC pin (TP12_2) must be brought high while keeping the EN pin (J3_2-2 or TP14_2) low. The device is then programmed via the I2C pins (SCL and SDA). In this circuit, the SCL pin is connected to TP10_2, and the SDA pin is connected to TP11_2. After the device is enabled, all registers are read-only. Details on the valid I2C registers and instructions are provided in the TPS542A50 data sheet.
An external signal (recommended 0-V to 3.3-V) can be used as an external clock synchronization source. To use this feature, the TPS542A50 must be enabled by bringing the EN pin (J3_2-2 or TP14_2) high, or leaving it floating. The external clock synchronization signal should be applied to the SYNC (TP12_2) pin, referenced to AGND. The external clock synchronization source must also be within -10% to +10% of the set switching frequency. This is true whether the switching frequency is selected using a resistor from FSEL to AGND (R6_2), or selected via I2C.