M27W400

M27W400 4 Mbit (512Kb x8 or 256Kb x16) Low Voltage UV EPROM and OTP EPROM s 2.7 to 3.6V LOW VOLTAGE in READ OPERATION READ ACCESS TIME: – 80ns at VCC = 3.0 to 3.6V – 100ns at VCC = 2.7 to 3.6V 40 40 s s BYTE-WIDE or WORD-WIDE CONFIGURABLE 4 Mbit MASK ROM REPLACEMENT LOW POWER CONSUMPTION – Active Current 20mA at 8MHz – Stand-by Current 15µA 1 1 FDIP40W (F) PDIP40 (B) s s s s s PROGRAMMING VOLTAGE: 12.5V ± 0.25V PROGRAMMING TIME: 50µs/word ELECTRONIC SIGNATURE – Manufacturer Code: 20h – Device Code: B8h Figure 1. Logic Diagram PLCC44 (K) DESCRIPTION The M27W400 is a low voltage 4 Mbit EPROM offered in the two range UV (Ultra Violet Erase) and OTP (one time programmable). It is ideally suited for microprocessor systems requiring large data or program storage. It is organised as either 512 Kwords of 8 bit or 256 Kwords of 16 bit. The pinout is compatible with the most common 4 Mbit Mask ROM. The M27W400 operates in the read mode with a supply voltage as low as 2.7V at –40 to 85°C temperature range. The decrease in operating power allows either a reduction of the size of the battery or an increase in the time between battery recharges. The FDIP40W (window ceramic frit-seal package) has a transparent lid which allows the user to expose the chip to ultraviolet light to erase the bit pattern. A new pattern can then be written to the device by following the programming procedure. For application where the content is programmed only one time and erasure is not required, th...