M87C257 STMICROELECTRONICS [STMicroelectronics], M87C257 Datasheet
M87C257
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M87C257 Summary of contents
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... ELECTRONIC SIGNATURE for AUTOMATED PROGRAMMING PROGRAMMING TIMES of AROUND 3sec. (PRESTO II ALGORITHM) DESCRIPTION The M87C257 is a high speed 262,144 bit UV erasable and electrically programmable EPROM. The M87C257 incorporates latches for all address inputs to minimize chip count, reduce cost, and simplify the design of multiplexed bus systems. ...
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... Minimum DC voltage on Input or Output is –0.5V with possible undershoot to –2.0V for a period less than 20ns. Maximum DC voltage on Output is V +0.5V with possible overshoot DEVICE OPERATION The modes of operation of the M87C257 are listed in the Operating Modes. A single power supply is required in the read mode. All inputs are TTL levels except for V and 12V on A9 for Electronic Signa- PP ture ...
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... Standby Mode The M87C257 has a standby mode which reduces the active current from 30mA to 100 A (Address Stable). The M87C257 is placed in the standby mode by applying a CMOS high signal to the E input. When in the standby mode, the outputs are in a high impedance state, independent of the G input ...
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... M87C257 Table 5. AC Measurement Conditions Input Rise and Fall Times Input Pulse Voltages Input and Output Timing Ref. Voltages Figure 3. AC Testing Input Output Waveform High Speed 3V 0V Standard 2.4V 0.4V (1) Table 6. Capacitance (T A Symbol Parameter C Input Capacitance IN C Output Capacitance OUT Note: 1. Sampled only, not 100% tested. ...
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... V PP M87C257 = 10 Min Max 100 100 –0.3 0 0.4 V – M87C257 -60 -70 - ...
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... and removed simultaneously or after V PP VALID tASLAX tAVASL tASHASL tASLGL tAVQV tGLQV tELQV = 10 M87C257 -10 -12 -15/-20 90 100 120 100 120 ...
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... CC Programming When delivered (and after each erasure for UV EPROM), all bits of the M87C257 are in the "1" state. Data is introduced by selectively program- ming "0"s into the desired bit locations. Although only "0"s will be programmed, both "1"s and "0"s can be present in the data word ...
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... Except for E, all like inputs including G of the parallel M87C257 may be common. A TTL low level pulse applied to a M87C257’s E input, with V will program that M87C257. A high level E input inhibits the other M87C257s from being pro- grammed. Program Verify ...
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... Research shows that constant exposure to room level fluorescent lighting could 5 C ambient erase a typical M87C257 in about 3 years, while it would take approximately 1 week to cause erasure when exposed to direct sunlight. If the M87C257 exposed to these types of lighting conditions for extended periods of time suggested that = 5V ...
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... M87C257 ORDERING INFORMATION SCHEME Example: M87C257 Speed V Tolerance CC ( blank - - - -10 100 ns -12 120 ns -15 150 ns -20 200 ns Note: 1. High Speed, see AC Characteristics section for further information. For a list of available options (Speed, V catalogue. For further information on any aspect of this device, please contact the SGS-THOMSON Sales Office nearest to you ...
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... M87C257 inches Typ Min 0.225 0.020 0.070 0.154 0.200 0.016 0.022 0.046 0.056 0.009 0.012 1.500 0.606 0.622 0.514 0.526 0.100 – 1.300 – 0.637 0.721 0.125 0.161 0.060 ...
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... M87C257 PLCC32 - 32 lead Plastic Leaded Chip Carrier, rectangular Symb Typ 1. PLCC32 Ne PLCC Drawing is not to scale 12/13 mm Min Max 2.54 3.56 1.52 2.41 0.33 0.53 0.66 0.81 12.32 12.57 11.35 11.56 9.91 10.92 14.86 15.11 13.89 14.10 12.45 13.46 – – 0. D2/E2 Nd inches Typ Min 0.100 0.140 0.060 0.095 0.013 0.021 0.026 ...
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... SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics. © 1996 SGS-THOMSON Microelectronics - All Rights Reserved SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A. M87C257 13/13 ...