24LC21A-I/P Microchip Technology, 24LC21A-I/P Datasheet
24LC21A-I/P
Specifications of 24LC21A-I/P
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24LC21A-I/P Summary of contents
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... Pb-Free and RoHS Compliant Description: The Microchip Technology Inc. 24LC21A is a 128 x 8-bit dual-mode Electrically Erasable PROM. This device is designed for use in applications requiring storage and serial transmission of configuration and control informa- tion. Two modes of operation have been implemented: Transmit-Only mode and Bidirectional mode ...
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... ELECTRICAL CHARACTERISTICS (†) Absolute Maximum Ratings V .............................................................................................................................................................................7.0V CC All inputs and outputs w.r. .........................................................................................................................................- Storage temperature ...............................................................................................................................-65°C to +150°C Ambient temperature with power applied ................................................................................................-40°C to +125°C ESD protection on all pins ......................................................................................................................................................≥ † NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device ...
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... Schmitt Trigger inputs which provide noise and specification for standard operation. I 24LC21A Units Remarks kHz (Note 1) ns (Note 1) ns After this period the first clock pulse is generated ns Only relevant for repeated ...
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... FUNCTIONAL DESCRIPTION The 24LC21A is designed to comply to the DDC Standard proposed by VESA (Figure 3-3) with the exception that it is not Access.bus capable. It operates in two modes, the Transmit-Only mode and the Bidirectional mode. There is a separate 2-wire protocol to support each mode, each having a separate clock input but sharing a common data line (SDA) ...
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... Bidirectional mode clock (SCL), controls access to the bus and generates the Start and Stop conditions, while the 24LC21A acts as the slave. Both master and slave can operate as transmitter or receiver, but the master device determines which mode is activated. In the Bidirectional mode, the 24LC21A only responds to commands for device ‘ ...
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... VESA’s Display Data Channel (DDC) Standard Proposal ver. 2p rev. 0, used by permission of VESA. 2: The dash box and text “The 24LC21A and... inside dash box.” are added by Microchip Technology Inc. 3: Vsync signal is normally used to derive a signal for VCLK pin on the 24LC21A. ...
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... Note: Once switched into Bidirectional mode, the 24LC21A will remain in that mode until power is removed. Removing power is the only way to reset the 24LC21A into the Transmit-Only mode. 3.1.5 ACKNOWLEDGE Each receiving device, when addressed, is obliged to generate an acknowledge after the reception of each byte ...
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... After generating a Start condition, the bus master transmits the slave address consisting of a 7-bit device code (1010000) for the 24LC21A. The eighth bit of slave address determines whether the master device wants to read or write to the 24LC21A (Figure 3-7). The 24LC21A monitors the bus for its corresponding slave address continuously ...
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... Page Write The write control byte, word address and the first data byte are transmitted to the 24LC21A in the same way byte write. But instead of generating a Stop condition the master transmits up to eight data bytes to the 24LC21A which are temporarily stored in the on- chip page buffer and will be written into the memory after the master has transmitted a Stop condition ...
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... FIGURE 4-1: BYTE WRITE Bus Activity R Master T SDA Line S Bus Activity VCLK FIGURE 4-2: VCLK WRITE ENABLE TIMING SCL SDA IN VCLK T VHST FIGURE 4-3: PAGE WRITE S T Bus Activity A Control Master R Byte T SDA Line Bus Activity K VCLK DS21160G-page 10 Word Control ...
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... Setting VCLK high allows normal write operations, while setting VCLK low prevents writing to any location in the array. Connecting the VCLK pin to V allow the 24LC21A to operate as a serial ROM, although this configuration would prevent using the device in the Transmit-Only mode. DS21160G-page 11 ...
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... Address Pointer is set. Then the master issues the control byte again but with the R/W bit set to a one. The 24LC21A will then issue an acknowledge and transmits the 8-bit data word. The master will not acknowledge the transfer but does generate a Stop condition and the 24LC21A discontinues transmission (Figure 7-2) ...
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... T A Bus Activity Control R Master Byte T SDA Line BUS Activity FIGURE 7-3: SEQUENTIAL READ Bus Activity Master Control Data n Byte SDA Line Bus Activity © 2008 Microchip Technology Inc Word Control R Address Byte Data n+2 Data n 24LC21A S T Data Data n DS21160G-page 13 ...
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... PIN DESCRIPTIONS 8.1 SDA This pin is used to transfer addresses and data into and out of the device, when the device is in the Bidirectional mode. In the Transmit-Only mode, which only allows data to be read from the device, data is also transferred on the SDA pin. This pin is an open drain terminal, ...
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... Standard marking consists of Microchip part number, year code, week code, traceability code (facility code, mask rev#, and assembly code). © 2008 Microchip Technology Inc. 24LC21A Example: 24LC21A I/PNNN 0145 Example: 24LC21A I/SN0145 NNN DS21160G-page 15 ...
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... DS21160G-page 16 PLO %RG\ >3',3@ © 2008 Microchip Technology Inc. ...
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... Microchip Technology Inc. 24LC21A PP %RG\ >62,&@ α φ β DS21160G-page 17 ...
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... DS21160G-page 18 PP %RG\ >62,&@ © 2008 Microchip Technology Inc. ...
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... APPENDIX A: REVISION HISTORY Revision F Corrections to Section 1.0, Electrical Characteristics. Revision G (07/2008) Features Section - Deleted Commercial Temp and added Pb-free; Revised Description; Table 1-1, Deleted Commercial Temp; Added Package Drawings: Revised Product ID section. © 2008 Microchip Technology Inc. 24LC21A DS21160G-page 19 ...
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... NOTES: DS21160G-page 20 © 2008 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 24LC21A should contact their distributor, DS21160G-page 21 ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Y Device: 24LC21A 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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... Device: 24LC21A Dual Mode Serial EEPROM 24LC21AT Dual Mode Serial EEPROM (Tape and Reel) Temperature I -40°C to +85°C Range: Package Plastic DIP (300 mil Body), 8-lead SN = Plastic SOIC (3.90 mm Body), 8-lead © 2008 Microchip Technology Inc. XXX Pattern 24LC21A . DS21160G-page 23 ...
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... NOTES: DS21160G-page 24 © 2008 Microchip Technology Inc. ...
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... PowerMate, PowerTool, REAL ICE, rfLAB, Select Mode, 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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... 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 © 2008 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 ...