SC23M28

HANGZHOU SILAN MICROELECTRONICS CO.,LTD

REV:1.0

2006.07.21

Http: www.silan.com.cn

Page 3 of 10

PIN CONFIGURATION

1

2

3

4

8

7

6

5

RST

CLK

NC

NC

NC

I/O

GND

(Contact of the card)

PIN DESCRIPTIONS

Pin No.

Symbol

I/O

Description

1

--

Power supply voltage is 5V

2

RST

I

Reset signal

3

CLK

I

Clock signal

4

NC

--

No connect

5

GND

--

Ground

6

NC

--

No connect

7

I/O

I/O

Data bus(open-drain output)

8

NC

--

No connect

FUNCTION DESCRIPTIONS

SC23M28 provides 1024×8 bits EEPROM memory units with write-protect for each bit. Except PSC

(Programmable Security Code) memory unit, all units are readable. The unit can be erased and written before the

write-protect is active, or else the unit is only readable. The bit with write-protection can be programmed only

once, and cannot be erased. The chip has one 8-bit error register which provides 8 times continuous PSC

authentication, after 8 times the chip cannot be erased and written.

1. Reset and reset acknowledge

The chip enters the power on reset state when it is power on, and this state will end by the reset signal. The

reset signal begins when RST changed from “0”to “1”, and end when CLK changed from “0”to“1”. The reset

signal can stop any active instruction. Read operation must be carried out first after power on reset, then the

other operations.

The reset acknowledge complies to ISO7816-3 synchronous propagation. The address counter is set to “0”

automatically and will send the first data to the I/O port. As the clock signal, the address data can be read serially.

The details refer to the figure 1.