參數(shù)資料
型號(hào): M27W256-200F6TR
廠商: 意法半導(dǎo)體
英文描述: 1-of-8 Data Selectors/Multiplexers 16-PDIP 0 to 70
中文描述: 256千位的32KB × 8低壓紫外線可擦寫可編程只讀存儲(chǔ)器和OTP存儲(chǔ)器
文件頁(yè)數(shù): 9/15頁(yè)
文件大?。?/td> 101K
代理商: M27W256-200F6TR
9/15
M27W256
On-Board Programming
The M27W256 can be directly programmed in the
application circuit. See the relevant Application
Note AN620.
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 matchthe device to be programmed
with its corresponding programming algorithm.
The ES mode is functional in the 25
°
C
±
5
°
C am-
bient temperaturerange that is required when pro-
gramming the M27W256. To activate the ES
mode, the programming equipment must force
11.5V to 12.5V on address line A9 of the
M27W256, with V
CC
= V
PP
= 5V. Two identifier
bytes maythen be sequenced fromthe device out-
puts bytoggling address line A0from V
IL
toV
IH
. All
other address lines must be held at V
IL
during
Electronic Signature mode. Byte 0 (A0 = V
IL
) rep-
resents the manufacturer code and byte 1 (A0 =
V
IH
)
the
device
identifier
STMicroelectronics M27W256,these two identifier
bytes are given in Table 4 and can be read-out on
outputs Q7 to Q0. Note that the M27W256 and
M27C256B have the same identifier bytes.
code.
For
the
ERASURE OPERATION (applies for UV EPROM)
The erasure characteristics of the M27W256 is
such that erasure begins when the cells are ex-
posed to light with wavelengths shorter than ap-
proximately 4000 . It should be noted that
sunlight and some type of fluorescent lamps have
wavelengths in the 3000-4000 range. Research
shows that constant exposure to room level fluo-
rescent lighting could erase a typical M27W256 in
about 3 years, while it would takeapproximately 1
week to cause erasure when exposed to direct
sunlight. If the M27W256 is to beexposed tothese
types of lighting conditions for extended periods of
time, it is suggested that opaque labelsbeput over
the M27W256 window to prevent unintentional
erasure. The recommended erasure procedure for
the M27W256is exposureto shortwave ultraviolet
light which has wavelength 2537. The integrated
dose (i.e. UV intensityx exposure time) for erasure
should be a minimum of 15 W-sec/cm
2
. The era-
sure time with this dosage is approximately 15 to
20 minutes using an ultraviolet lamp with 12000
μ
W/cm
2
power rating. The M27W256 should be
placed within 2.5 cm (1 inch) of the lamp tubes
during the erasure. Some lamps have a filter on
their tubes which should be removed before era-
sure.
相關(guān)PDF資料
PDF描述
M27W256-200K6TR 1-of-8 Data Selectors/Multiplexers 16-PDIP 0 to 70
M27W256-200N6TR 1-of-8 Data Selectors/Multiplexers 16-SO 0 to 70
M27W256-80B6TR 1-of-8 Data Selectors/Multiplexers 16-SO 0 to 70
M27W256-80F6TR 1-of-8 Data Selectors/Multiplexers 16-SO 0 to 70
M27W256-80K6TR Dual 1-of-4 Data Selectors/Multiplexers 16-SOIC 0 to 70
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
M27W256-200K6TR 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:256 Kbit 32Kb x 8 Low Voltage UV EPROM and OTP EPROM
M27W256-200N6TR 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:256 Kbit 32Kb x 8 Low Voltage UV EPROM and OTP EPROM
M27W256-80B6TR 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:256 Kbit 32Kb x 8 Low Voltage UV EPROM and OTP EPROM
M27W256-80F6TR 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:256 Kbit 32Kb x 8 Low Voltage UV EPROM and OTP EPROM
M27W256-80K6TR 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:256 Kbit 32Kb x 8 Low Voltage UV EPROM and OTP EPROM