APGRD001 Microchip Technology, APGRD001 Datasheet - Page 4

• Manufacturer Part Number: APGRD001
• Description: REF DESIGN PKE PIC16F639
• Manufacturer: Microchip Technology
• Type: PKE, RKEr

Specifications of APGRD001

• Frequency: 125kHz
• Processor To Be Evaluated: PIC16F639
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PIC16F639, PIC16F636, PIC18F2680
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

AN1024
Wake-up Filter and Signal Detection
Users can program one of the nine possible Output
Enable filters using the Configuration registers. Refer to
the PIC12F635/PIC16F636/639 Device Data Sheet
(DS41232) for more details (see “References”).
Figures 3 and 4
demodulated outputs. The input signal is applied to one
of the three input pins or on all pins (LCX, LCY, LCZ) at
the same time. The outputs are available on the
LFDATA pin of the device. The figures show the
differences in output pins depending on the setting of
the output enable (wake-up) filter option. For the cases
shown in Figure 3 and Figure 4, the minimum
FIGURE 3:
FIGURE 4:
DS01024B-page 4
show
INPUT SIGNAL AND DEMODULATED OUTPUT WHEN OUTPUT ENABLE FILTER IS
ENABLED AND INPUT MEETS THE FILTER TIMING REQUIREMENT
INPUT SIGNAL AND DEMODULATED OUTPUT WHEN OUTPUT ENABLE FILTER IS
ENABLED AND INPUT DOES NOT MEET THE FILTER TIMING REQUIREMENT
examples
of
inputs
and
modulation depth requirement is set to 8% and the
Output Enable Filter is set to (T
The input signal amplitude is 2.7 mV
modulation depth of about 9%. Figure 3 shows the
input signal and the demodulated data output after the
wake-up filter is matched. The demodulated output of
the correct (wanted) input signal wakes up the digital
section, and will respond if the command is valid.
Figure 4 shows the case when the input does not meet
the programmed filter requirement. The demodulated
output is not available at the output pin since the input
does not meet the programmed filter requirement. This
ensures that the digital section will not wake-up due to
unwanted input signals.
© 2007 Microchip Technology Inc.
OEH
: 2 ms, T
OEL
PP
= 2 ms).
with a