HMN4M8D

Features:

· Access time : 70, 85, 120, 150 ns
· High-density design : 32Mbit Design
· Battery internally isolated until power is applied
· Industry-standard 40-pin 4,096K x 8 pinout
· Unlimited write cycles
· Data retention in the absence of V_CC
· 5-years minimum data retention in absence of power
· Automatic write-protection during power-up/power-down cycles
· Data is automatically protected during power loss
· Industrial temperature operation






Pinout




Specifications

PARAMETER	SYMBOL	RATING	CONDITIONS
DC voltage applied on VCC relative to VSS	VCC	-0.5V to 7.0V
DC Voltage applied on any pin excluding VCC relative to VSS	VT	-0.3V to 7.0V
Operating temperature	TOPR	0 to 70	Commercial
		-40 to 85	Industrial
Storage temperature	TSTG	-55 to 125
Temperature under bias	TBIAS	-40 to 85
Soldering temperature	TSOLDER	260	For 10 second

NOTE: Permanent device damage may occur if Absolute Maximum Ratings are exceeded.
           Functional operation should be restricted to the Recommended DC Operating Conditions detailed in this
          data sheet.
          Exposure to higher than recommended voltage for extended periods of time could affect device reliability.


Description

The HMN4M8D Nonvolatile SRAM is a 33,554,432-bit static RAM organized as 4,194,304 bytes by 8 bits.

The HMN4M8D has a self-contained lithium energy source provide reliable non-volatility coupled with the unlimited write cycles of standard SRAM and integral control circuitry which constantly monitors the single 5V supply for an out-oftolerance condition. When such a condition occurs, the lithium energy source is automatically switched on to sustain the memory until after V_CC returns valid and write protection is unconditionally enabled to prevent garbled data. In addition the SRAM is unconditionally write-protected to prevent an inadvertent write operation. At this time the integral energy source is switched on to sustain the memory until after V_CC returns valid.

The HMN4M8D uses extremely low standby current CMOS SRAM's, coupled with small lithium coin cells to provide nonvolatility without long write-cycle times and the write-cycle limitations associated with EEPROM.