Set The Operating Frequency - Murata Psemi Pe25203 User Manual
Evaluation kit divide-by-2 and -3, 4a charge pump, capacitor divider
Table of Contents
PE25203
EVK User's Manual
Set the Operating Frequency
Use the FREQ pin to set the PE25203 operating frequency. To save a resistor, you can also connect the FREQ
pin to GND to oscillate at a nominal 200 kHz. This is the oscillation frequency at the VX pin and the charge pump
frequency per phase switches at 50% of this value.
To adjust the frequency, connect a resistor between 82.5 KΩ and 505 KΩ between the FREQ pin and GND. Use
the following equation to find the required VX switching period in µs:
VX switching period = (0.0093 * resistance value in kΩ) + 0.2254
Using a resistor value of 499 KΩ in the equation above,
VX switching period = (0.0093 * 499) +0.2254 = 4.87µs (205 kHz)
Figure 7 shows the VX switching period vs. the resistance value set at the FREQ pin.
Figure 7. VX Switching Period vs. Resistance Value on the FREQ Pin
©2023–2025, pSemi Corporation. All rights reserved. • Headquarters: 9369 Carroll Park Drive, San Diego, CA, 92121
Page 12 of 31
DOC-111189-2 – (02/2025)
www.psemi.com
Table of Contents
Need help?
Do you have a question about the pSemi PE25203 and is the answer not in the manual?