M27V320 datasheet(11/15 Pages) STMICROELECTRONICS

11 / 15 page

11/15

M27V320

Electronic Signature

The Electronic Signature (ES) mode allows the

reading out of a binary code from an EPROM that

will identify its manufacturer and type. This mode

is intended for use by programming equipment to

automatically match the device to be programmed

with its corresponding programming algorithm.

The ES mode is functional in the 25°C ± 5°C am-

bient temperature range that is required when pro-

gramming the M27V320. To activate the ES mode,

the programming equipment must force 11.5V to

12.5V on address line A9 of the M27V320, with

VPP = VCC = 5V. Two identifier bytes may then be

sequenced from the device outputs by toggling ad-

dress line A0 from VIL to VIH. All other address

lines must be held at VIL during Electronic Signa-

ture mode.

Byte 0 (A0 = VIL) represents the manufacturer

code and byte 1 (A0 = VIH) the device identifier

code. For the STMicroelectronics M27V320, these

two identifier bytes are given in Table 4 and can be

read-out on outputs Q7 to Q0.

M27V320 Datasheet(PDF) 11 Page - STMicroelectronics