HCS473 Datasheet, PDF (54/68 Pages) Microchip Technology – Code Hopping Encoder and Transponder

HCS473
TABLE 7-3: AC CHARACTERISTICS, FOSC = 4 MHz⁽¹⁾
AC Characteristics
FOSC = 4 MHz⁽¹⁾
The min and max values below are due to HCS473 algorithm tolerances,
not variations due to supply voltage and temperature.
Symbol
Min
Typ
Max
Description
General HCS473 Timing
TDB
—
10 ms
—
TQUE
—
2s
—
TPU
—
10.9 ms
—
TPLL
—
19 ms
—
TLEDON
—
100 ms
—
TLEDOFF
—
500 ms
—
Communication from Transponder Reader to HCS473
TCMD
1LFTE+100 µs
—
10.2 ms
TTSCMD
1LFTE+100 µs
—
10.2 ms
TFINH
100 µs
1LFTE
—
Response from HCS473 to Transponder Reader
TSF
1ms+1LFTE
3.5ms+1LFTE
10ms+1LFTE
TTSACK
1LFTE+16 µs
1LFTE-11 µs
1LFTE+30 µs
1 LFTE
1LFTE+44 µs
1LFTE+11 µs
TTPACK
157 µs
179 µs
212 µs
TWRT
—
4 ms
10 ms
TAOACK
67 µs
89 µs
122 µs
TIFF
—
5.64ms
—
TREAD
205 µs
227 µs
260 µs
THOP
—
19 ms
—
TDAMP
—
1.2 LFTE
—
TDEMOD
—
16.4 ms
—
Debounce Time
Que Window
Power-up Delay Time (includes button debounce)
Encoder Mode PLL activation to first code word
LED ON Time
LED OFF Time
Delay from Transponder Select ACK to next command
Time to leave LF on after last data bit’s rising edge
Delay to wake-up Acknowledge sequence
Delay from TID pulse rising edge to TID Acknowledge
TID = 0
TID > 0
Delay to Transport Code Acknowledge
Delay to Write Acknowledge
Delay to anticollision off Acknowledge
Delay to IFF response - RF or LF response
Delay to read response - RF or LF response
Delay to hopping code response - RF or LF response
Delay from detecting LC rising edge to first damp pulse
Demodulator mode window looking for edge on LC pin
Timing Element TE
TE
RFTE or LFTE
90
100
110
RFBSL = LFBSL = 00₂
180
200
220
RFBSL = LFBSL = 01₂
360
400
440
RFBSL = LFBSL = 10₂
720
800
880
RFBSL = LFBSL = 11₂
Analog delays
TFILTR
—
15 µs
—
HCS473 analog LF filter charge time
TFILTF
—
70 µs
—
HCS473 analog LF filter discharge time
TANTR
Hardware design dependent
Cumulative LF antenna delay when field is turned on
TANTF
Hardware design dependent
Cumulative LF antenna delay when field is turned off
Note 1: FOSC = 4 MHz may be centered at the designer’s choice of supply voltage (VDD) and temperature.
2: LFTE is based on the HCS473’s timing, not the timing of the transponder reader. Therefore LFTE is subject to HCS473
oscillator variation.
3: Response timing accounts for TFILTR but not for TANTR or TANTF, as they are design dependent. The system designer
must compensate communication accordingly for TANTR and TANTF.
4: Timing parameters are characterized but not tested.
DS40035C-page 52
Preliminary
 2002 Microchip Technology Inc.