Microchip logo
  • All
  • Products
  • Documents
  • Applications Notes
  • product video
  • product video
product primary image

24LC21A

1Kb I2C Serial EEPROM for DDC1™/DDC2™ Monitor Identification

Status: In Production

Features:

  • Single Supply with Operation Down to 2.5V
  • Completely Implements DDC1™/DDC2™ Interface for Monitor Identification, Including Recovery to DDC1
  • Pin and Function Compatible with 24LC21
  • Low-Power CMOS Technology
  • 2-Wire Serial Interface Bus, I2C™ Compatible
  • 100 kHz (2.5V) and 400 kHz (5V) Compatibility
  • Self-Timed Write Cycle (including auto-erase)
  • Page Write Buffer for up to Eight Bytes
  • 1,000,000 Erase/Write Cycles Ensured
  • Data Retention > 200 years
View More
Overview
Documents
Development Environment
Similar Devices
RoHS Information
Add To Cart

Device Overview

Summary

The Microchip Technology Inc. 24LC21A 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 information. 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 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™Compatible 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 memory array using SCL. If no control byte is received, the device will revert to the Transmit-Only mode after it receives 128 consecutive VCLK pulses while the SCL pin is idle. The 24LC21A is available in a standard 8-pin PDIP and SOIC package in industrial temperature range.

Additional Features
  • Single Supply with Operation Down to 2.5V
  • Completely Implements DDC1™/DDC2™Interface for Monitor Identification, IncludingRecovery to DDC1
  • Pin and Function Compatible with 24LC21
  • Low-Power CMOS Technology
  • 2-Wire Serial Interface Bus, I2C™ Compatible
  • 100 kHz (2.5V) and 400 kHz (5V) Compatibility
  • Self-Timed Write Cycle (including auto-erase)
  • Page Write Buffer for up to Eight Bytes
  • 1,000,000 Erase/Write Cycles Ensured
  • Data Retention > 200 years
Parametrics
Name
Value
Density
1K bits (x8)
Op. Volt Range (V)
2.5 to 5.5
Max. Clock Freq.
400 kHz
Page Size (bytes)
8
Temp Range (°C)
-40°C to +85°C
Endurance
1,000,000

Documents

Jump to:

Data Sheets

  
337KB

Supporting Collateral

Development Environment

  • Production Programmers
  • Demo & Evaluation Boards
Production Programmers
Softlog SEC-DS Secure Programming Upgrade for ICP2 Programmers
Softlog SEC-DS Secure Programming Upgrade for ICP2 Programmers ( SW500090 )

The Softlog SEC-DS Secure Programming Upgrade is a "Secure Programming" extension for the ICP2 and ICP2(HC) programmers that provides several layers of protection--utilizing breakthrough technology--dramatically reducing the risk of unauthorized reconstruction of hex data and limiting how many times a hex file can be programmed. Secure programming operates on two levels: the ADMIN level and the...

Learn More
Add To Cart
Softlog SEC4CH-DS Secure Programming Upgrade for ICP2GANG Programmers
Softlog SEC4CH-DS Secure Programming Upgrade for ICP2GANG Programmers ( SW500091 )

The Softlog SEC4CH-DS Secure Programming Upgrade is a "Secure Programming" extension for the ICP2GANG programmer that provides several layers of protection--utilizing breakthrough technology--dramatically reducing the risk of unauthorized reconstruction of hex data and also limiting how many times a hex file can be programmed. Secure programming operates on two levels: the ADMIN level and the USER...

Learn More
Add To Cart
Softlog ICP2(G3) ICSP Production Programmer
Softlog ICP2(G3) ICSP Production Programmer ( TPG100001-G3 )

The ICP2(G3) Production Quality In-Circuit Programmer is a cost-effective programmer that operates with a PC or as a standalone unit. It programs 8-bit PIC® / AVR® MCUs and Serial EEPROMs & Flash ICs. ICP2(G3) hardware is designed to support popular programming interfaces (ICSP™, JTAG, SWD, UPDI, SPI, QSPI, etc.)

Learn More
Add To Cart
Softlog ICP2(G3)-DP ICSP Production Programmer
Softlog ICP2(G3)-DP ICSP Production Programmer ( TPG100002-G3 )

The ICP2(G3)-DP Production Quality In-Circuit Programmer is a cost-effective programmer that operates with a PC or as a standalone unit. It programs 8-bit PIC® & AVR® MCUs, 16-bit PIC MCUs & dsPIC® DSCs and Serial EEPROMs & Flash ICs. ICP2(G3)-DP hardware is designed to support popular programming interfaces (ICSP™, JTAG, SWD, UPDI, SPI, QSPI,

...

Learn More
Add To Cart
Softlog ICP2GANG(G3)-DP 4-Channel ICSP Production Gang Programmer
Softlog ICP2GANG(G3)-DP 4-Channel ICSP Production Gang Programmer ( TPG100004-G3 )

The ICP2GANG(G3)-DP Production Quality In-Circuit 4-channel (expandable to 64 channels) GANG programmer is a cost-effective programmer that operates with a PC or as a standalone unit and simultaneously programs 8-bit PIC® & AVR® MCUs, 16-bit PIC MCUs & dsPIC® DSCs, and serial EEPROMs & Flash ICs. ICP2GANG(G3)-DP hardware is designed to support popular programming

...

Learn More
Add To Cart
Softlog ICP2GANG(G3) 4-Channel ICSP Production Gang Programmer
Softlog ICP2GANG(G3) 4-Channel ICSP Production Gang Programmer ( TPG100005-G3 )

The ICP2GANG(G3) Production Quality In-Circuit 4-channel (expandable to 64 channels) GANG programmer is a cost-effective programmer that operates with a PC or as a standalone unit and simultaneously programs 8-bit PIC® & AVR® MCUs and serial EEPROMs & Flash ICs. ICP2GANG(G3) hardware is designed to support popular programming interfaces (ICSP™, JTAG, SWD, UPDI, SPI, QSPI,

...

Learn More
Add To Cart
Softlog ICP2GANG(G3)-DS ICSP Secure Production Gang Programmer
Softlog ICP2GANG(G3)-DS ICSP Secure Production Gang Programmer ( TPG100006-G3 )

The ICP2GANG(G3)-DS Production Quality ICSP Secure GANG Programmer is a 4-channel in-circuit programmer (expandable up to 64 channels) that operates with a PC or as a standalone unit and simultaneously programs 8-bit PIC® & AVR® MCUs and serial EEPROMs & Flash ICs. The secure programming feature dramatically reduces the risk of unauthorized

...

Learn More
Add To Cart
Softlog ICP2(G3)-DS ICSP Secure Production Programmer
Softlog ICP2(G3)-DS ICSP Secure Production Programmer ( TPG100007-G3 )

The ICP2(G3)-DS Production Quality Secure Programmer is an in-circuit programmer that operates with a PC or as a standalone unit, and programs 8-bit PIC® & AVR® MCUs and serial EEPROMs & Flash ICs. The secure programming feature dramatically reduces the risk of unauthorized reconstruction of hex files, and also limits how many times the hex file can be programmed. ICP2(G3)-DS

...

Learn More
Add To Cart
Softlog ICP2(HC) ICSP High-Current Production Programmer
Softlog ICP2(HC) ICSP High-Current Production Programmer ( TPG100008 )

The Softlog ICP2(HC) Production Quality In-Circuit High Current Programmer is a cost-effective programmer that operates with a PC or as a standalone unit.

Note: All technical support and warranty service will be provided by Softlog. You can contact them at support@softlog.com.

Learn More
Add To Cart
Softlog ICP2PORT(G3) Portable In-Circuit Production Programmer
Softlog ICP2PORT(G3) Portable In-Circuit Production Programmer ( TPG100009-G3 )

A member of the ICP(G3) family of high-speed, production-grade in-circuit programmers. This compact, battery-powered device supports up to six different programming environments, making it an ideal, low-cost solution for field upgrades. ICP2PORT(G3) programs Microchip 8-bit PIC® & AVR® MCUs and Serial EEPROMs & Flash ICs. ICP2PORT(G3) hardware is designed to support popular

...

Learn More
Add To Cart
Softlog ICP2PORT(G3)-P Portable In-Circuit Production Programmer
Softlog ICP2PORT(G3)-P Portable In-Circuit Production Programmer ( TPG100010-G3 )

A member of the ICP(G3) family of high-speed, production-grade in-circuit programmers. This compact, battery-powered device supports up to six different programming environments, making it an ideal, low-cost solution for field upgrades. ICP2PORT(G3)-P programs Microchip 8-bit PIC® & AVR® MCUs, 16-bit PIC MCUs & dsPIC® DSCs and Serial EEPROMs & Flash ICs. ICP2PORT(G3)-P

...

Learn More
Add To Cart
Softlog ICP2PORT(G3)-PX Portable In-Circuit Production Programmer
Softlog ICP2PORT(G3)-PX Portable In-Circuit Production Programmer ( TPG100011-G3 )

A member of the ICP(G3) family of high-speed, production-grade in-circuit programmers. This compact, battery-powered device supports up to six different programming environments, making it an ideal, low-cost solution for field

...

Learn More
Add To Cart
Softlog ICP2(G3)-DPX ICSP Production Programmer
Softlog ICP2(G3)-DPX ICSP Production Programmer ( TPG100012-G3 )

The ICP2(G3)-DPX Production Quality In-Circuit Programmer is a cost-effective programmer that operates with a PC or as a standalone unit. It programs 8-bit PIC® & AVR® MCUs, 16-bit PIC MCUs & dsPIC® DSCs, 32-bit PIC & ARM Cortex M0/0+/23/3/4/7 MCUs and Serial EEPROMs & Flash ICs. ICP2(G3)-DPX hardware is designed to support popular programming interfaces

...

Learn More
Add To Cart
Softlog ICP2GANG(G3)-DPX ICSP 4-Channel Gang Programmer
Softlog ICP2GANG(G3)-DPX ICSP 4-Channel Gang Programmer ( TPG100013-G3 )

The ICP2GANG(G3)-DPX Production Quality In-Circuit 4-channel (expandable to 64 channels) GANG programmer is a cost-effective programmer that operates with a PC or as a standalone unit and simultaneously programs 8-bit PIC® & AVR® MCUs, 16-bit PIC MCUs & dsPIC® DSCs, 32-bit PIC & ARM Cortex M0/0+/23/3/4/7 MCUs and Serial EEPROMs & Flash ICs. ICP2GANG(G3)-DPX

...

Learn More
Add To Cart
Softlog ICP2COMBO(G3)-DPX-8 8-Channel Gang Programmer
Softlog ICP2COMBO(G3)-DPX-8 8-Channel Gang Programmer ( TPG100015-G3 )

The ICP2COMBO(G3)-DPX-8 Production Quality In-Circuit (ICSP) 8-channel (expandable up to 64 channels) GANG Programmer is a cost-effective programmer that operates with a PC or as a standalone unit and simultaneously programs 8-bit PIC® & AVR® MCUs, 16-bit PIC MCUs & dsPIC® DSCs, 32-bit PIC & ARM Cortex M0/0+/23/3/4/7 MCUs and Serial EEPROMs & Flash

...

Learn More
Add To Cart
Softlog ICP2COMBO(G3)-12 12-Channel Gang Programmer
Softlog ICP2COMBO(G3)-12 12-Channel Gang Programmer ( TPG100016-G3 )

The ICP2COMBO(G3)-12 Production Quality In-Circuit (ICSP) 12-channel (expandable up to 60 channels) GANG Programmer is a cost-effective programmer that operates with a PC or as a standalone unit and simultaneously programs 8-bit PIC® & AVR® MCUs and serial EEPROMs & Flash ICs. ICP2COMBO(G3)-12 hardware is designed to support popular programming interfaces (ICSP™, JTAG,

...

Learn More
Add To Cart
Softlog ICP2COMBO(G3)-8 8-Channel Gang Programmer
Softlog ICP2COMBO(G3)-8 8-Channel Gang Programmer ( TPG100017-G3 )

The ICP2COMBO(G3)-8 Production Quality In-Circuit (ICSP) 8-channel (expandable up to 64 channels) GANG Programmer is a cost-effective programmer that operates with a PC or as a standalone unit and simultaneously programs 8-bit PIC® & AVR® MCUs and serial EEPROMs & Flash ICs. ICP2COMBO(G3)-8 hardware is designed to support popular programming interfaces (ICSP™, JTAG,

...

Learn More
Add To Cart
Demo & Evaluation Boards
Serial EEPROM PIM PICtail Pack
Serial EEPROM PIM PICtail Pack ( AC243003 )

The Serial EEPROM PIM PICtail™ Modules are a series of boards designed around Microchip Serial EEPROM devices. The boards are designed to interface with the PICtail Plus connector as well as the MPLAB® Starter Kit for Serial Memory Products and the PICkit™ 2, allowing you to get started right out of the box.

Learn More
Add To Cart
MPLAB Starter Kit for Memory Products
MPLAB Starter Kit for Memory Products ( DV243003 )

Designers of Serial EEPROM applications can enjoy the increased productivity, reduced time to market and rock-solid design that only a well thought out development system can provide. Microchip's MPLAB® Starter Kit for Serial Memory Products includes everything necessary to quickly develop a robust and reliable Serial EEPROM design, and greatly reduces the time required for system

...

Learn More
Add To Cart

Similar Devices

Product
Memory Size
Memory Speed
Package
Price 5K
1K
400 kHz
DFN-8, MSOP-8, PDIP-8, SC70-5, SOIC-8, SOT-23-5, TDFN-8, TSSOP-8
$0.14
1K
400 kHz
DFN-8, MSOP-8, PDIP-8, SOIC-8, SOT-23-6, TDFN-8, TSSOP-8
$0.19
1K
400 kHz
MSOP-8, PDIP-8, SOIC-8, TDFN-8, TSSOP-8
$0.20
1K
400 kHz
MSOP-8, PDIP-8, SC70-5, SOIC-8, SOT-23-5, TDFN-8, TSSOP-8
$0.14
1K
400 kHz
DFN-8, MSOP-8, PDIP-8, SOIC-8, SOT-23-6, TDFN-8, TSSOP-8
$0.19
1K
1 MHz
MSOP-8, PDIP-8, SOIC-8, SOT-23-5, UDFN-8
$0.08
1K
400 kHz
DFN-8, MSOP-8, PDIP-8, SOIC-8, SOT-23-6, TDFN-8, TSSOP-8
$0.19
1K
1000 kHz
MSOP-8, PDIP-8, SOIC-8, TDFN-8, TSSOP-8
$0.20
1K
400 kHz
DFN-8, MSOP-8, PDIP-8, SC70-5, SOIC-8, SOT-23-5, TDFN-8, TSSOP-8
$0.14
1K
400 kHz
MSOP-8, PDIP-8, SC70-5, SOIC-8, SOT-23-5, TDFN-8, TSSOP-8
$0.14
1K
400 kHz
PDIP-8, SOIC-8
$0.29
1K
400 kHz
PDIP-8, SOIC-8
$0.29
1K
400 kHz
MSOP-8, PDIP-8, SOIC-8, SOT-23-6, TDFN-8, TSSOP-8
 
1K
400 kHz
MSOP-8, PDIP-8, SOIC-8, TDFN-8, TSSOP-8
 
 
1 MHz
WLCSP-4
$0.15

RoHS Information

Part Number
Device Weight (g)
Shipping Weight (Kg)
Lead Count
Package Type
Package Width
Solder Composition
JEDEC Indicator
RoHS
China EFUP
24LC21A/SN
0.078000
0.250000
8
SOIC
.1China RoHs 50.pngIn(3.90mm)
Matte Tin
e3
24LC21A-I/SN
0.078000
0.250000
8
SOIC
.1China RoHs 50.pngIn(3.90mm)
Matte Tin
e3
24LC21A-I/SN100
0.078000
0.250000
8
SOIC
.1China RoHs 50.pngIn(3.90mm)
Matte Tin
e3
24LC21AT/SN
0.078000
0.230303
8
SOIC
.1China RoHs 50.pngIn(3.90mm)
Matte Tin
e3
24LC21AT-I/SN
0.078000
0.230303
8
SOIC
.1China RoHs 50.pngIn(3.90mm)
Matte Tin
e3
24LC21AT-I/SN100
0.078000
0.230303
8
SOIC
.1China RoHs 50.pngIn(3.90mm)
Matte Tin
e3
24LC21A-I/P
0.486700
0.900000
8
PDIP
.300in
Matte Tin
e3
24LC21A-I/PREL
0.486700
0.900000
8
PDIP
.300in
Matte Tin
e3
24LC21A/P
0.486700
0.900000
8
PDIP
.300in
Matte Tin
e3
To see a complete listing of RoHS data for this device, please Click here
Shipping Weight = Device Weight + Packing Material weight. Please contact sales office if device weight is not available.

Buy from Microchip

Grid
View
Table
View
Filter:
Apply
Clear
Only show products with samples
Product
Leads
Package Type
Temp Range
Packing Media
5K Pricing
Buy