25LC640A-M/SN Microchip Technology, 25LC640A-M/SN Datasheet
25LC640A-M/SN
Specifications of 25LC640A-M/SN
Related parts for 25LC640A-M/SN
25LC640A-M/SN Summary of contents
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... Page Size Temp. Ranges 32 Byte M Description: The Microchip Technology Inc. 25LC640A kbit Serial Electrically Erasable PROM. The memory is accessed via a simple Serial Peripheral Interface (SPI) compatible serial bus. The bus signals required are a clock input (SCK) plus separate data in (SI) and data out (SO) lines ...
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... ELECTRICAL CHARACTERISTICS (†) Absolute Maximum Ratings V .............................................................................................................................................................................6.5V CC All inputs and outputs w.r.t. V ......................................................................................................... -0. Storage temperature .................................................................................................................................-65°C to 150°C Ambient temperature under bias ...............................................................................................................-55°C to 125°C ESD protection on all pins ..........................................................................................................................................4 kV † NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device ...
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... Vcc < 4.5V 40 — ns 4.5V ≤ Vcc ≤ 5.5V(Note 1) 30 — ns 2.5V ≤ Vcc < 4.5V(Note 1) 60 — ns 4.5V ≤ Vcc ≤ 5.5V 30 — ns 2.5V ≤ Vcc < 4.5V 60 — ns — OTE 1M — E/W (N OTE Cycles 25LC640A V = 2.5V to 5.5V CC Test Conditions 3) 2) DS22144A-page 3 ...
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... TABLE 1-3: AC TEST CONDITIONS AC Waveform 100 pF L Timing Measurement Reference Level Input Output ≤ 4.0V Note 1: For For V > 4.0V CC DS22144A-page 4 — (Note 1) (Note 2) — © 2009 Microchip Technology Inc. ...
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... CS 2 Mode 1,1 Mode 0,0 SCK MSB in SO FIGURE 1-3: SERIAL OUTPUT TIMING SCK 13 MSB out SO SI © 2009 Microchip Technology Inc High-Impedance n Don’t Care High-Impedance 14 Don’t Care 25LC640A LSB in 3 Mode 1,1 Mode 0,0 15 ISB out DS22144A-page 5 ...
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... CS pin (Figure 2-1). DS22144A-page 6 2.3 Write Sequence Prior to any attempt to write data to the 25LC640A, the write enable latch must be set by issuing the WREN instruction (Figure 2-4). This is done by setting CS low ® and then clocking out the proper instruction into the 25LC640A ...
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... Read data from memory array beginning at selected address Write data to memory array beginning at selected address Reset the write enable latch (disable write operations) Set the write enable latch (enable write operations) Read STATUS register Write STATUS register 16-bit Address 25LC640A Description 0 Data Out DS22144A-page 7 ...
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... FIGURE 2-2: BYTE WRITE SEQUENCE SCK Instruction High-Impedance SO FIGURE 2-3: PAGE WRITE SEQUENCE SCK Instruction SCK Data Byte DS22144A-page 16-bit Address 16-bit Address Data Byte Twc Data Byte Data Byte Data Byte n (32 max © 2009 Microchip Technology Inc. ...
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... Write Enable (WREN) and Write Disable (WRDI) The 25LC640A contains a write enable latch. See Table 2-4 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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... X X BP1 BP0 W/R = writable/readable read-only. The Write-In-Process (WIP) bit indicates whether the 25LC640A is busy with a write operation. When set to a ‘ ’, a write is in progress, when set to a ‘ progress. This bit is read-only. FIGURE 2-6: READ STATUS REGISTER TIMING SEQUENCE (RDSR) ...
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... See Figure 2-7 for the WRSR timing sequence. TABLE 2-3: BP1 Data to STATUS Register High-Impedance ) is initiated on the rising edge of CS after a valid write STATUS register 25LC640A ARRAY PROTECTION Array Addresses BP0 Write-Protected none 0 upper 1/4 1 (1800h-1FFFh) upper 1/2 0 (1000h-1FFFh) all 1 (0000h-1FFFh ...
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... DS22144A-page 12 2.8 Power-On State The 25LC640A powers on in the following state: • The device is in low-power Standby mode ( • The write enable latch is reset • high-impedance state • A high-to-low-level transition required to enter active state Protected Blocks ...
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... CS is required prior to any sequence being initiated. 3.2 Serial Output (SO) The SO pin is used to transfer data out of the 25LC640A. During a read cycle, data is shifted out on this pin after the falling edge of the serial clock. 3.3 Write-Protect (WP) This pin is used in conjunction with the WPEN bit in the STATUS register to prohibit writes to the nonvolatile bits in the STATUS register ...
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... PACKAGING INFORMATION 4.1 Package Marking Information 8-Lead SOIC XXXXXXXT XX/XXYYWW NNN Legend: XX...X Customer-specific information Y Year code (last digit of calendar year) YY Year code (last 2 digits of calendar year) WW Week code (week of January 1 is week ‘01’) NNN Alphanumeric traceability code ...
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... Microchip Technology Inc. 25LC640A PP %RG\ >62,&@ α φ β DS22144A-page 15 ...
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... DS22144A-page 16 PP %RG\ >62,&@ © 2009 Microchip Technology Inc. ...
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... APPENDIX A: REVISION HISTORY Revision A (03/2009) Initial release of this document. © 2009 Microchip Technology Inc. 25LC640A DS22144A-page 17 ...
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... NOTES: DS22144A-page 18 © 2009 Microchip Technology Inc. ...
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... Customers representative or field application engineer (FAE) for support. Local sales offices are also available to help customers. A listing of sales offices and locations is included in the back of this document. Technical support is available through the web site at: http://support.microchip.com 25LC640A should contact their distributor, DS22144A-page 19 ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Y Device: 25LC640A Questions: 1. What are the best features of this document? 2. How does this document meet your hardware and software development needs you find the organization of this document easy to follow? If not, why? 4 ...
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... Range: Package Plastic SOIC (3.90 mm body), 8-lead © 2009 Microchip Technology Inc. /XX X Examples: Package a) b) 25LC640A . 25LC640A-M/ Kbit, 2.5V Serial EEPROM, Extended temp., SOIC package 25LC640AT-M/ Kbit, 2.5V Serial EEPROM, Extended temp., Tape and Reel, SOIC package DS22144A-page 21 ...
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... NOTES: DS22144A-page 22 © 2009 Microchip Technology Inc. ...
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... PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. ...
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... Fax: 886-3-572-6459 Taiwan - Kaohsiung Tel: 886-7-536-4818 Fax: 886-7-536-4803 Taiwan - Taipei Tel: 886-2-2500-6610 Fax: 886-2-2508-0102 Thailand - Bangkok Tel: 66-2-694-1351 Fax: 66-2-694-1350 © 2009 Microchip Technology Inc. EUROPE Austria - Wels Tel: 43-7242-2244-39 Fax: 43-7242-2244-393 Denmark - Copenhagen Tel: 45-4450-2828 Fax: 45-4485-2829 France - Paris Tel: 33-1-69-53-63-20 ...