Be careful when choosing ICs with strange crystal frequencies.

It seems quite simple when one thinks of choosing a frequency to operate ones crystal oscillator for timing, PLLs etc. However, apart from the obvious issues associated with the actual operation of the circuit it becomes important to select a crystal frequency that is relatively easy to source. For instance we have a RF transmitter and a RF receiver. This time we chose these off the shelf instead of developing our own chip. The transmitter has a crystal frequency of 14.3 Mhz. This is an easy one to source. Digikey has a number of these crystals for immediate delivery. However, the receiver crystal frequency is specified as 14.464063 Mhz. This is a killer. We cannot source this crystal easily. There is a long wait for it and many dollars for development. So we are now in a predicament. After much deliberation we are going with a crystal oscillator dissipating 32 mA for our first demo system. The issue is that the battery will be discharged very quickly. The search for the correct crystal continues…

We design and deliver analog and RF/wireless ASICs and modules using state of the art semiconductor, PCB and assembly technologies. Please contact us at for a quote and a proposal.

Leave a Reply