Philips Semiconductors
Preliminary data
Low power, low price, low pin count (20 pin)
microcontroller with 4 kbyte OTP
87LPC764
THE OSCILLATOR MUST BE CONFIGURED IN ONE OF
THE FOLLOWING MODES:
QUARTZ CRYSTAL OR
CERAMIC RESONATOR
– LOW FREQUENCY CRYSTAL
– MEDIUM FREQUENCY CRYSTAL
– HIGH FREQUENCY CRYSTAL
87LPC764
X1
X2
CAPACITOR VALUES MAY BE OPTIMIZED FOR
DIFFERENT OSCILLATOR FREQUENCIES (SEE TEXT)
*
A SERIES RESISTOR MAY BE REQUIRED IN ORDER TO
LIMIT CRYSTAL DRIVE LEVELS. THIS IS PARTICULARLY
IMPORTANT FOR LOW FREQUENCY CRYSTALS (SEE TEXT).
SU01165
Figure 16. Using the Crystal Oscillator
87LPC764
CMOS COMPATIBLE EXTERNAL
OSCILLATOR SIGNAL
X1
X2
THE OSCILLATOR MUST BE CONFIGURED IN
THE EXTERNAL CLOCK INPUT MODE.
A CLOCK OUTPUT MAY BE OBTAINED ON
THE X2 PIN BY SETTING THE ENCLK BIT IN
THE P2M1 REGISTER.
SU01166
Figure 17. Using an External Clock Input
22
2001 Oct 26
NXP [ NXP ]
