24LCS22A
2K VESA® E-EDID™ Serial EEPROM
Features:
Package Types
PDIP/SOIC
• Single Supply with Operation Down to 2.5V
• Supports Enhanced EDID™ (E-EDID™) 1.3
• Completely Implements DDC1™/DDC2™ Inter-
face for Monitor Identification, including Recovery
to DDC1
*NC
*NC
1
2
8
7
VCC
VCLK
• 2 Kbit Serial EEPROM Low-Power CMOS
Technology:
WP
VSS
3
4
6
5
SCL
SDA
- 1 mA active current, typical
- 10 μA standby current, typical at 5.5V
• 2-Wire Serial Interface Bus, I2C™ Compatible
• 100 kHz (2.5V) and 400 kHz (5V) Compatibility
• Self-Timed Write Cycle (including Auto-Erase)
• Hardware Write-Protect Pin
* Pins labeled ‘NC’ have no internal connection
• Page Write Buffer for up to Eight Bytes
• 1,000,000 Erase Write Cycles
Block Diagram
• Data Retention >200 years
WP
• ESD Protection >4000V
HV Generator
• 8-pin PDIP and SOIC Packages
• Available Temperature Ranges:
I/O
Control
Logic
Memory
Control
Logic
- Industrial (I)
-40°C to +85°C
EEPROM
Array
XDEC
• Pb-Free and RoHS Compliant
Page Latches
Description:
SDA
SCL
The Microchip Technology Inc. 24LCS22A is a 256 x 8-bit
dual-mode Electrically Erasable PROM (EEPROM). This
device is designed for use in applications requiring
storage and serial transmission of configuration and
control information. Two modes of operation have been
implemented: Transmit-Only mode (1 Kbit) and
Bidirectional mode (2 Kbit). Upon power-up, the device
will be in the Transmit-Only mode, sending a serial bit
stream of the memory array from 00h to 7Fh, clocked by
the VCLK pin. A valid high-to-low transition on the SCL pin
will cause the device to enter the Transition mode, and
look for a valid control byte on the I2C bus. If it detects a
valid control byte from the master, it will switch into
Bidirectional mode, with byte selectable read/write
capability of the entire 2K memory array using SCL. If no
control byte is received, the device will revert to the Trans-
mit-Only mode after it receives 128 consecutive VCLK
pulses while the SCL pin is idle. The 24LCS22A is avail-
able in standard 8-pin PDIP and SOIC packages. The
24LCS22A features a flexible write-protect pin which is
enabled by writing to address 7Fh (usually the checksum
in VESA® applications.
YDEC
VCLK
Sense Amp.
R/W Control
Vcc
Vss
© 2008 Microchip Technology Inc.
DS21682D-page 1