HCS500

© 1997 Microchip Technology Inc.

Preliminary

DS40153B-page 13

FIGURE 4-9:

ERASE ALL

FIGURE 4-10: STAND-ALONE MODE LEARN/ERASE-ALL TIMING

FIGURE 4-11: TYPICAL STAND-ALONE APPLICATION CIRCUIT

Decoder DATA

MSB

A

Command Byte

Start Command

B

C

LSB

D

E

Subcommand Byte

Dummy Byte

CLK

µC DATA

F

Acknowledge

MSB

LSB

MSB

LSB

DATA

A

Erase-All Activation

CLK

B

C

D

Learn Activation

Successful

E

OUTPUT

K1

RELAY SPST

Vcc

Vcc

S1

LEARN

1K

A0

1

A1

2

A2

3

4

SDA 5

SCL 6

WP 7

U2

24LC02B

1

EECLK

2

EEDAT

3

MCLR

4

SDAT 5

SCLK 6

RFIN 7

8

U1

HCS500

Q1

NPN

R1

10K

D1

LED

R2

10K

R3

10K

VI

G

N

D

VO

U3

POWER SUPPLY

X

X

X

RF

Receiver

SUPERVISOR 4.5V

22

µF

Note:

Because each HCS500 is individually matched to its EEPROM, in-circuit programming is

strongly recommended.

In-circuit

Programming

Probe Pads