View 274001 datasheet:

M27C4001 4 Megabit (512K x 8) UV EPROM and OTP ROM VERY FAST ACCESS TIME: 70ns COMPATIBLE with HIGH SPEED MICROPROCESSORS, ZERO WAIT STATE LOW POWER ”CMOS” CONSUMPTION: – Active Current 30mA at 5MHz 28 – Standby Current 100µA 1 PROGRAMMING VOLTAGE: 12.75V ELECTRONIC SIGNATURE for AUTOMATED FDIP32W (F) LCCC32W (L) PROGRAMMING PROGRAMMING TIMES of AROUND 48sec. (PRESTO II ALGORITHM) DESCRIPTION The M27C4001 is a high speed 4 Megabit UV erasable and programmable memory (EPROM) PLCC32 (C) TSOP32 (N) ideally suited for microprocessor systems requiring 8 x 20mm largeprograms.It isorganised as524,288by 8bits. The 32 pin Window Ceramic Frit-Seal Dual-in-Line and Leadless Chip Carrier packages have trans- Figure 1. Logic Diagram parent lids which allow the user to expose the