RFPIC12C509AG Microchip Technology Inc., RFPIC12C509AG Datasheet - Page 37

• Manufacturer Part Number: RFPIC12C509AG
• Description: 18/20-pin 8-bit Cmos Microcontroller With Uhf Ask/fsk Transmitter
• Manufacturer: Microchip Technology Inc.

7.3.1
The rfPIC12C509AG or 509AF crystal oscillator can be
configured for ASK operation. Figure 7-2 shows an
example ASK circuit.
Capacitor C1 trims the crystal load capacitance to the
circuit load capacitance and places the crystal on the
desired frequency.
TABLE 7-2:
©
2001 Microchip Technology Inc.
Note 1: Standard Operating Conditions (unless otherwise stated) T
1000 pF
100 pF
150 pF
470 pF
22 pF
39 pF
CRYSTAL OSCILLATOR ASK
OPERATION
C1
f
XTAL
XTAL OSC APPROXIMATE FREQ. VS. CAPACITANCE (ASK MODE)
= 13.55 MHz
Predicted Frequency
13.551438
13.550563
13.549844
13.549672
13.549548
13.549344
(MHz)
Preliminary
PPM from 13.55 MHz
rfPIC12C509AG/509AF
FIGURE 7-2:
+106
+42
-12
-24
-33
-48
A
= 25°C, RF
X1
C1
CRYSTAL CIRCUIT
EXAMPLE ASK EXTERNAL
Transmit Frequency (MHz) (32 *
EN
= 1, V
XTAL
rfPIC12C509AG/
DDRF
433.5895
433.5856
433.646
433.618
433.595
433.579
f
XTAL
509AF
(1)
= 3V,
DS70031A-page 35
)