25AA256 Microchip Technology, 25AA256 Datasheet
25AA256
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25AA256 Summary of contents
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... SI Serial Data Input SCK Serial Clock Input HOLD Hold Input V Supply Voltage CC * 25XX256 is used in this document as a generic part number for the 25AA256, 25LC256 devices. © 2007 Microchip Technology Inc. 25AA256/25LC256 256K SPI Bus Serial EEPROM V Range Page Size CC 2.5-5.5V 64 Byte 1 ...
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... ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings V .............................................................................................................................................................................6.5V CC All inputs and outputs w.r. Storage temperature .................................................................................................................................-65°C to 150°C Ambient temperature under bias ...............................................................................................................-40°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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... This parameter is not tested but ensured by characterization. For endurance estimates in a specific application, please consult the Total Endurance™ Model which can be obtained from Microchip’s web site at www.microchip.com. © 2007 Microchip Technology Inc. 25AA256/25LC256 Industrial (I -40°C to +85°C A Automotive (E -40° ...
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... TABLE 1-2: AC CHARACTERISTICS (CONTINUED) AC CHARACTERISTICS Param. Sym. Characteristic No HOLD Low to Output HZ High HOLD High to Output HV Valid 20 T Internal Write Cycle WC Time 21 — Endurance Note 1: This parameter is periodically sampled and not 100% tested begins on the rising edge of CS after a valid write sequence and ends when the internal write cycle WC is complete ...
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... SERIAL OUTPUT TIMING CS SCK MSB out SO SI © 2007 Microchip Technology Inc High-Impedance Don’t Care High-Impedance Don’t Care 25AA256/25LC256 LSB ISB out DS21822F-page Mode 1,1 Mode 0,0 ...
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... FUNCTIONAL DESCRIPTION 2.1 Principles of Operation The 25XX256 is a 32,768-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 PIC microcontrollers. It may also interface with microcon- trollers that do not have a built-in SPI port by using discrete I/O lines programmed properly in firmware to match the SPI protocol ...
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... Set the write enable latch (enable write operations) 0000 0110 0000 0101 Read STATUS register Write STATUS register 0000 0001 16-bit Address High-Impedance 25AA256/25LC256 Description Data Out DS21822F-page 7 0 ...
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... FIGURE 2-2: BYTE WRITE SEQUENCE SCK Instruction FIGURE 2-3: PAGE WRITE SEQUENCE SCK Instruction SCK Data Byte DS21822F-page ...
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... Power-up See • WRDI instruction successfully executed • WRSR instruction successfully executed • WRITE instruction successfully executed SCK High-Impedance SCK High-Impedance SO 25AA256/25LC256 DS21822F-page 9 ...
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... Read Status Register Instruction (RDSR) The Read Status Register instruction (RDSR) provides access to the STATUS register. The STATUS register may be read at any time, even during a write cycle. The STATUS register is formatted as follows: TABLE 2-2: STATUS REGISTER W W/R WPEN BP1 ...
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... See Figure 2-7 for the WRSR timing sequence. TABLE 2- Instruction High-Impedance ) is initiated on the rising edge of CS after a valid write STATUS register WC 25AA256/25LC256 ARRAY PROTECTION Array Addresses BP1 BP0 Write-Protected none upper 1/4 (6000h-7FFFh) upper 1 (4000h-7FFFh) all 1 1 ...
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... Data Protection The following protection has been implemented to prevent 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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... Serial Clock Input 1 Hold Input 2 Supply Voltage 25AA256/25LC256 The WP pin function is blocked when the WPEN bit in the STATUS register is low. This allows the user to install the 25XX256 in a system with WP pin grounded and still be able to write to the STATUS register. The WP pin functions will be enabled when the WPEN bit is set high ...
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... YYWWNNN 1L7 Example: TSSOP 1st Line Marking Codes 5LE Device I528 25AA256 1L7 25LC256 Part number or part number code Temperature (I, E) Year code (last digit of calendar year) Year code (last 2 digits of calendar year) Week code (week of January 1 is week ‘01’) ...
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... EXPOSED PAD 2 1 TOP VIEW φ NOTE 2 Units Dimension Limits MIN 0. 3. 2.16 b 0.35 L 0.50 K 0.20 φ 25AA256/25LC256 NOTE 1 D2 BOTTOM VIEW MILLIMETERS NOM MAX 8 1.27 BSC – 0.85 1.00 – 0.65 0.80 0.01 0.05 0.20 REF 4.92 BSC 4.67 BSC 4.00 4.15 5.99 BSC 5.74 BSC 2.31 2.46 0.40 0.47 0.60 0.75 – ...
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... Plastic Dual In-Line (P) – 300 mil Body [PDIP] Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging NOTE Number of Pins Pitch Top to Seating Plane Molded Package Thickness Base to Seating Plane ...
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... Microchip Technology Inc φ A2 Units Dimension Limits § φ α β 25AA256/25LC256 α β MILLIMETERS MIN NOM MAX 8 1.27 BSC – – 1.75 1.25 – – 0.10 – 0.25 6.00 BSC 3.90 BSC 4.90 BSC 0.25 – 0.50 0.40 – ...
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... Standard, Formerly called SOIC) 8-Lead Plastic Small Outline (SM) – Medium, 5.28 mm Body [SOIJ] Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging Number of Pins Pitch Overall Height Molded Package Thickness Standoff § ...
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... REF: Reference Dimension, usually without tolerance, for information purposes only. © 2007 Microchip Technology Inc Units Dimension Limits φ 25AA256/25LC256 φ L MILLIMETERS MIN NOM MAX 8 0.65 BSC – – 1.20 0.80 1.00 1.05 0.05 – 0.15 6.40 BSC 4.30 4.40 4.50 2.90 3.00 3.10 0.45 0.60 0.75 1.00 REF 0° ...
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... APPENDIX A: REVISION HISTORY Revision C (11/03) Corrections to Section 1.0, Electrical Characteristics. Revision D (06/05) Update package information Revision E (08/05) Remove Preliminary status. Revise Table 1-1, Params. D011 and D012. Revision F (05/07) Update Pb-free; Replace Package Drawings (Rev. AP); Update Product ID section. DS21822F-page 20 © 2007 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 25AA256/25LC256 should contact their distributor, DS21822F-page 21 ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Device: 25AA256/25LC256 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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... TSSOP, 8-lead = Plastic SOIC (5.28 mm body), 8-lead 25AA256/25LC256 . Examples: a) 25AA256T-I/SN = 256k-bit, 1.8V Serial EEPROM, Industrial temp., Tape & Reel, SOIC package b) 25AA256T-I/ST = 256k-bit, 1.8V Serial EEPROM, Industrial temp., Tape & Reel, TSSOP package c) 25LC256-I/P = 256k-bit, 2.5V Serial EEPROM, Industrial temp., P-DIP package d) 25LC256T-E/ST = 256k-bit, 2.5V EEPROM, Extended temp., Tape & Reel, ...
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... NOTES: DS21822F-page 24 © 2007 Microchip Technology Inc. ...
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... PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, Select Mode, Smart Serial, SmartTel, Total Endurance, UNI/O, 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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... Tel: 45-4450-2828 Fax: 45-4485-2829 France - Paris Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79 Germany - Munich Tel: 49-89-627-144-0 Fax: 49-89-627-144-44 Italy - Milan Tel: 39-0331-742611 Fax: 39-0331-466781 Netherlands - Drunen Tel: 31-416-690399 Fax: 31-416-690340 Spain - Madrid Tel: 34-91-708-08-90 Fax: 34-91-708-08- Wokingham Tel: 44-118-921-5869 Fax: 44-118-921-5820 12/08/06 © 2007 Microchip Technology Inc. ...