ST24LC21

ST24LC21 1Kb (x8) DUAL MODE SERIAL EEPROM for VESA Plug&Play NOT FOR NEW DESIGN 1 MILLION ERASE/WRITE CYCLES 40 YEARS DATA RETENTION 2.5V to 5.5V SINGLE SUPPLY VOLTAGE 400k Hz COMPATIBILITY OVER the FULL RANGE of SUPPLY VOLTAGE TWO WIRE SERIAL INTERFACE I2C BUS COMPATIBLE PAGE WRITE (up to 8 BYTES) BYTE, RANDOM and SEQUENTIAL READ MODES SELF TIMED PROGRAMMING CYCLE AUTOMATIC ADDRESS INCREMENTING ENHANCED ESD/LATCH UP PERFORMANCES ST24LC21 is replaced by the ST24LC21B 8 1 PSDIP8 (B) 0.25mm Frame 8 1 SO8 (M) Figure 1. Logic Diagram DESCRIPTION The ST24LC21 is a 1K bit electrically erasable programmable memory (EEPROM), organized by 8 bits.This device can operate in two modes: Transmit Only mode and I2C bidirectional mode. When powered, the device is in Transmit Only mode with EEPROM data clocked out from the rising edge of the signal applied on VCLK. The device will switch to the I2C bidirectional mode upon the falling edge of the signal applied on SCL pin. The ST24LC21 cannot switch from the I2C bidirectional mode to the Transmit Only mode (except when the power supply is removed). The device operates with a power supply value as low as 2.5V. Both Plastic Dual-in-Line and Plastic Small Outline packages are available. VCC SCL ST24LC21 VCLK SDA Table 1. Signal Names SDA SCL VCC VSS VCLK Serial Data Address Input/Output Serial Clock (I C mode) Supply Voltage Ground Clock Transmit only mode 2 VSS AI01489 June 1997 This is information on a product still in production but ...