KEELOQ®数据编码器振荡器校准

Several KEELOQ Encoders of recent introduction, offer
the ability to calibrate the internal RC clock oscillator,
upon which all the device timings are based. At the time
of writing this Application Note, there are five KEEL OQ
devices offering this feature:
• HCS101 - fixed code encoder
• HCS201 - low cost hopping code encoder
• HCS362 - advanced hopping code encoder
• HCS410 - hopping code transcoder
• HCS412 - hopping code transcoder
While the respective Encoder Data Sheets show
“where” the calibration value is stored in the device
EEPROM, this Application Note will concentrate on
“how to” determine the best calibration value.
AN824
KEELOQ Encoders Oscillator Calibration
Typically, this oscillator provides the clock frequency
Author: Lucio Di Jasio with a wide tolerance (up to -30%/+50%) and that
Microchip Technology Inc. reflects in ample tolerances on the transmission baud
rate, LED flashing and, in general, on most device tim-
ings. Further, being a simple RC clock circuit, it is
affected by