FEATURES
® Data retention in the absence of power ® Automatic write-protection during power-up/power-down cycles ® Industry-standard 40-pin 128K x 16 pinout ® Conventional SRAM operation; unlimited write cycles ® 10-year minimum data retention in absence of power ® Battery internally isolated until power is applied GENERAL DESCRIPTION
The CMOS When VCC falls out of tolerance, the SRAM is unconditionally writeprotected to prevent an inadvertent write operation. At this time the integral energy source is switched on to sustain the memory until after VCC returns valid. The bq4024 uses extremely low standby current CMOS SRAMs, coupled with small lithium coin cells to provide nonvolatility without long write-cycle times and the write-cycle limitations associated with EEPROM. The bq4024 requires no external circuitry and is compatible with the industry-standard 2Mb SRAM pinout. Pin Connections NC CE DQ15 DQ14 DQ13 DQ12 DQ11 DQ10 DQ9 DQ8 VSS DQ7 DQ6 DQ5 DQ4 DQ3 DQ2 DQ1 DQ0 OE 1 2 3 4 5 6 7 8...