DS1211

DS1211 Nonvolatile Controller x 8 Chip www.dalsemi.com FEATURES Converts full CMOS RAMs into nonvolatile memories Unconditionally write protects when VCC is out of tolerance Automatically switches to battery when power-fail occurs 3 to 8 decoder provides control for up to eight CMOS RAMs Consumes less than 100 nA of battery current Tests battery condition on power-up Provides for redundant batteries Power-fail signal can be used to interrupt processor on power failure Optional 5% or 10% power-fail detection Optional 20-pin SOIC surface mount package Optional industrial temperature range of -40°C to +85°C PIN ASSIGNMENT VBAT1 VCCO TOL PF CE7 CE6 C B A GND 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 VCCI VBAT2 CE CE0 CE1 CE2 CE3 NC CE4 CE5 VBAT1 VCCO TOL PF CE7 CE6 C B A GND 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 VCCI VBAT2 CE CE0 CE1 CE2 CE3 NC CE4 CE5 20-Pin DIP (300-mil) See Mech. Drawings Section 20-Pin SOIC (300-mil) See Mech. Drawings Section PIN DESCRIPTION A, B, C CE CE0 - Address Inputs - Chip Enable Input - Chip Enable Outputs - Ground - + Battery 1 - + Battery 2 - Power Supply Tolerance - +5V Supply - RAM Supply - Power-fail - No Connection - CE7 GND VBAT1 VBAT2 TOL VCCI VCC0 PF NC DESCRIPTION The DS1211 Nonvolatile Controller x 8 Chip is a CMOS circuit which solves the application problem of converting CMOS RAMs into nonvolatile memories. Incoming power is monitored for an out-oftolerance condition. When such a condition is detected, th...