24LCS21_13 Datasheet, PDF (1/24 Pages) Microchip Technology – 1K 2.5V Dual Mode I2C™ Serial EEPROM

Not recommended for new designs –
Please use 24LCS21A.
24LCS21
1K 2.5V Dual Mode I²C^™ Serial EEPROM
Features:
• Completely implements DDC1^™/DDC2^™ interface
for monitor identification
• Hardware write-protect pin
• Single supply with operation down to 2.5V
• Low-power CMOS technology:
- 1 mA active current, typical
- 10 A standby current, typical at 5.5V
• 2-wire serial interface bus, I²C^™ compatible (SCL)
• Self-timed write cycle (including auto-erase)
• Page-write buffer for up to 8 bytes
• 100 kHz (2.5V) and 400 kHz (5V) compatibility
(SCL)
• 1,000,000 erase/write cycles ensured
• Data retention > 200 years
• 8-pin PDIP and SOIC package
• Available for extended temperature ranges:
- Commercial (C):
- Industrial (I)
0°C to +70°C
-40°C to +85°C
Description:
The Microchip Technology Inc. 24LCS21 is a 128 x 8-bit
dual-mode Electrically Erasable PROM. This device is
designed for use in applications requiring storage and
serial transmission of configuration and control informa-
tion. Two modes of operation have been implemented:
Transmit-Only mode and Bidirectional mode. Upon
power-up, the device will be in the Transmit-Only mode,
sending a serial bit stream of the entire memory array
contents, clocked by the VCLK pin. A valid high-to-low
transition on the SCL pin will cause the device to enter
the Bidirectional mode, with byte selectable read/write
capability of the memory array in standard I²C protocol.
The 24LCS21 also enables the user to write-protect the
entire memory contents using its write-protect pin. The
24LCS21 is available in a standard 8-pin PDIP and
SOIC package in both commercial and industrial
temperature ranges.
Package Types
PDIP
NC 1
NC 2
WP 3
VSS 4
SOIC
NC ¹
NC ²
WP ³
VSS ⁴
8 VCC
7 VCLK
6 _SCL
5 SDA
8 _VCC
7 _VCLK
6 _SCL
5 _SDA
Block Diagram
WP
I/O
Control
Logic
Memory
Control
Logic
XDEC
SDA SCL
VCC
VSS
VCLK
HV Generator
EEPROM
Array
Page Latches
YDEC
Sense Amp
R/W Control
 1995-2012 Microchip Technology Inc.
DS21127G-page 1