Document
128K
X24128
400KHz 2-Wire Serial E2PROM with Block LockTM
DESCRIPTION
16K x 8 Bit
FEATURES
•
• •
•
• • • • • • • • •
Save Critical Data with Programmable Block Lock Protection —Block Lock (0, 1/4, 1/2, or all of E2PROM Array) —Software Write Protection —Programmable Hardware Write Protect In Circuit Programmable ROM Mode 400KHz 2-Wire Serial Interface —Schmitt Trigger Input Noise Suppression —Output Slope Control for Ground Bounce Noise Elimination Longer Battery Life With Lower Power —Active Read Current Less Than 1mA —Active Write Current Less Than 3mA —Standby Current Less Than 1µA 1.8V to 3.6V, 2.5V to 5.5V and 4.5V to 5.5V Power Supply Versions 32 Word Page Write Mode —Minimizes Total Write Time Per Word Internally Organized 16K x 8 Bidirectional Data Transfer Protocol Self-Timed Write Cycle —Typical Write Cycle Time of 5ms High Reliability —Endurance: 100,000 Cycles —Data Retention: 100 Years 14-Lead SOIC 16-Lead SOIC 8-Lead PDIP
The X24128 is a CMOS Serial E2PROM, internally organized 16K x 8. The device features a serial interface and software protocol allowing operation on a simple two wire bus. Three device select inputs (S0–S2) allow up to eight devices to share a common two wire bus. A Write Protect Register at the highest address location, FFFFh, provides three write protection features: Software Write Protect, Block Lock Protect, and Programmable Hardware Write Protect. The Software Write Protect feature prevents any nonvolatile writes to the device until the WEL bit in the Write Protect Register is set. The Block Lock Protection feature gives the user four array block protect options, set by programming two bits in the Write Protect Register. The Programmable Hardware Write Protect feature allows the user to install the device with WP tied to VCC, write to and Block Lock the desired portions of the memory array in circuit, and then enable the In Circuit Programmable ROM Mode by programming the WPEN bit HIGH in the Write Protect Register. After this, the Block Locked portions of the array, including the Write Protect Register itself, are permanently protected from being erased.
FUNCTIONAL DIAGRAM
SERIAL E2PROM DATA AND ADDRESS (SDA) DATA REGISTER Y DECODE LOGIC COMMAND DECODE AND CONTROL LOGIC BLOCK LOCK AND WRITE PROTECT CONTROL LOGIC S2 S1 S0 DEVICE SELECT LOGIC WRITE PROTECT REGISTER 8K x 8 SERIAL E2PROM ARRAY 16K x 8 4K x 8
SCL
PAGE DECODE LOGIC
4K x 8
WP
©Xicor, 1995, 1996 Patents Pending 7027-1.3 5/14/97 T2/C0/D2 SH
WRITE VOLTAGE CONTROL
7027 FM 01
1
Characteristics subject to change without notice
X24128
Xicor E2PROMs are designed and tested for applications requiring extended endurance. Inherent data retention is greater than 100 years. PIN DESCRIPTIONS Serial Clock (SCL) The SCL input is used to clock all data into and out of the device. Serial Data (SDA) SDA is a bidirectional pin used to transfer data into and out of the device. It is an open drain output and may be wire-ORed with any number of open dra.