HCS500 Datasheet, PDF (13/24 Pages) Microchip Technology – KEELOQ CODE HOPPING ENCODER

HCS500
FIGURE 4-9: ERASE ALL
TERA
CLK
µC DATA
LSB
MSB LSB
MSB LSB
MSB
Decoder DATA
Start Command
A
B
Command Byte
Subcommand Byte
Dummy Byte
C
D
E
FIGURE 4-10: STAND-ALONE MODE LEARN/ERASE-ALL TIMING
TPP1
TPP2
TPP3
TACK
TRESP
TACK2
Acknowledge
F
TPP4
CLK
DATA
A
Learn Activation
B
C
Erase-All Activation
FIGURE 4-11: TYPICAL STAND-ALONE APPLICATION CIRCUIT
VCC
RF
Receiver
U2
XXX1234
A0
A1
A2
VSS
VCC
WP
SCL
SDA
8
7
6
5
24LC02B
1K
1
2
3
4
U1
VDD
EECLK
EEDAT
MCLR
VSS
RFIN
SCLK
SDAT
8
7
6
5
HCS500
22 µF
VCC
U3
POWER SUPPLY
SUPERVISOR 4.5V
VI _G VO
N
D
Vcc
S1
LEARN
R1
10K
R3
R2
10K
10K
D1
LED
Successful
D
E
OUTPUT
Vcc
K1
RELAY SPST
Q1
NPN
In-circuit
Programming
Probe Pads
Note: Because each HCS500 is individually matched to its EEPROM, in-circuit programming is
strongly recommended.
© 1997 Microchip Technology Inc.
Preliminary
DS40153B-page 13