JAJSMY6 April 2022 TPSM63604
PRODUCTION DATA
Synchronize the internal oscillator of the TPSM63604 by AC coupling a positive clock edge to EN/SYNC, as shown in Figure 8-1. The synchronization frequency range is 200 kHz to 2.2 MHz.
It is recommended to keep the parallel combination value of RENT and RENB in the 100-kΩ range. RENT is required for synchronization, but RENB can be left open. The external clock must be off before start-up to allow proper start-up sequencing. After a valid synchronization signal is applied for 2048 cycles, the clock frequency changes to that of the applied signal.
Referring to Figure 8-2, the AC-coupled voltage edge at the EN/SYNC pin must exceed the SYNC amplitude threshold, VEN_SYNC, of 2.4 V to trip the internal synchronization pulse detector. In addition, the minimum EN/SYNC rising and falling pulse durations must be longer than the SYNC signal hold time, tSYNC_EDGE, of 100 ns and shorter than the minimum blanking time, tB. Use a 3.3-V or higher amplitude pulse signal coupled through a 1-nF capacitor, designated as CSYNC in Figure 8-1.