25AA640 MICROCHIP [Microchip Technology], 25AA640 Datasheet
25AA640
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25AA640 Summary of contents
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... While the device is paused, transi- tions on its inputs will be ignored, with the exception of chip select, allowing the host to service higher priority interrupts. *25xx640 is used in this document as a generic part number for the 25AA640/25LC640/25C640 devices. SPI is a trademark of Motorola. 1997 Microchip Technology Inc. ™ ...
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... ELECTRICAL CHARACTERISTICS 1.1 Maximum Ratings* Vcc ...................................................................................7.0V All inputs and outputs w.r.t. Vss.................. -0.6V to Vcc+1.0V Storage temperature ....................................... -65˚C to 150˚C Ambient temperature under bias..................... -65˚C to 125˚C Soldering temperature of leads (10 seconds) ............. +300˚C ESD protection on all pins.................................................4kV *Notice: Stresses above those listed under ‘Maximum ratings’ may cause permanent damage to the device ...
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... This parameter is periodically sampled and not 100% tested. 2: This parameter is not tested but guaranteed by characterization. For endurance estimates in a specific application, please consult the Total Endurance Model which can be obtained on Microchip’s BBS or website. 1997 Microchip Technology Inc. 25AA640/25LC640/25C640 Tamb = + Tamb = - +85 C ...
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... FIGURE 1-2: HOLD TIMING CS T SCK SO n+2 n+1 n+2 n+1 SI HOLD FIGURE 1-3: SERIAL INPUT TIMING CS T CSS Mode 1,1 Mode 0,0 SCK Tsu MSB in SO FIGURE 1-4: SERIAL OUTPUT TIMING SCK T V MSB out SO SI DS21223A-page high impedance n don’t care ...
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... The WP pin function is blocked when the WPEN bit in the status register is low. This allows the user to install the 25AA640/25LC640/25C640 in a system with WP pin grounded and still be able to write to the status reg- ister. The WP pin functions will be enabled when the WPEN bit is set high ...
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... FUNCTIONAL DESCRIPTION 3.1 PRINCIPLES OF OPERATION The 25xx640 is a 8192 byte Serial EEPROM designed to interface directly with the Serial Peripheral Interface (SPI) port of many of today’s popular microcontroller families, including Microchip’s PIC16C6X/7X micro- controllers. It may also interface with microcontrollers that do not have a built-in SPI port by using discrete I/O lines programmed properly with the software ...
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... SCK data byte 1997 Microchip Technology Inc. 25AA640/25LC640/25C640 bit address bit address ...
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... Write Enable (WREN) and Write Disable (WRDI) The 25xx640 contains a write enable latch. Table 3-3 for the Write Protect Functionality Matrix. This latch must be set before any write operation will be completed internally. The WREN instruction will set the latch, and the WRDI will reset the latch. ...
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... SI SO 1997 Microchip Technology Inc. 25AA640/25LC640/25C640 divided up into four segments. The user has the ability to write protect none, one, two, or all four of the seg- ments of the array. The partitioning is controlled as illustrated in Table 3-2. The Write Protect Enable (WPEN) bit is a non-volatile bit that is available as an enable bit for the WP pin ...
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... Data Protection The following protection has been implemented to pre- vent inadvertent writes to the array: • The write enable latch is reset on power-up. • A write enable instruction must be issued to set the write enable latch. • After a byte write, page write, or status register write, the write enable latch is reset. • ...
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... PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office. 25xx640 — /P Package: Temperature Range: Devices: Sales and Support Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recom- mended workarounds ...
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M W ORLDWIDE AMERICAS Corporate Office Microchip Technology Inc. 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 602-786-7200 Fax: 602-786-7277 Technical Support: 602 786-7627 Web: http://www.microchip.com Atlanta Microchip Technology Inc. 500 Sugar Mill Road, Suite 200B Atlanta, GA 30350 Tel: ...