24lc22a Microchip Technology Inc., 24lc22a Datasheet
24lc22a
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24lc22a Summary of contents
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... SCL control byte is received, the device will revert to the Transmit-Only mode after it receives 128 consecutive VCLK pulses while the SCL pin is idle. The 24LC22A is available in standard 8-pin PDIP and SOIC packages. © 2007 Microchip Technology Inc. ...
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... ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings† V .............................................................................................................................................................................7.0V CC All inputs and outputs w.r.t. V ......................................................................................................... -0. Storage temperature ...............................................................................................................................-65°C to +150°C Ambient temp. with power applied ..........................................................................................................-40°C to +125°C Soldering temperature of leads (10 seconds) .......................................................................................................+240°C ESD protection on all pins ......................................................................................................................................................≥ †Notice: Stresses above those listed under “Maximum ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operational listings of this specification is not implied ...
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... Units Conditions 2.5V ≤ V ≤ 5.5V kHz CC 4.5V ≤ V ≤ 5.5V CC 2.5V ≤ V ≤ 5. 4.5V ≤ V ≤ 5.5V CC 2.5V ≤ V ≤ 5. 4.5V ≤ V ≤ 5.5V CC 2.5V ≤ V ≤ 5.5V (Note 1) ...
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... FUNCTIONAL DESCRIPTION The 24LC22A is designed to comply to the DDC Stan- dard 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 (1 Kbit) and the Bidirectional mode (2 Kbit). 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 Before the 24LC22A can be switched into the Bidirec- tional mode (Figure 3-1), it must enter the Transition mode, which is done by applying a valid high-to-low transition on the Bidirectional mode clock (SCL). As soon it enters the Transition mode, it looks for a control 2 byte ‘1010 000X’ on the I C™ ...
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... Yes Valid Access.bus Yes address? Yes Yes See Access.bus No specification to determine correct procedure. Yes The 24LC22A was designed to comply to the portion of flowchart inside dash box. Yes ® No Yes Receive DDC2B command Respond to DDC2B command No No © 2007 Microchip Technology Inc. ...
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... Note: Once switched into Bidirectional mode, the 24LC22A will remain in that mode until power is removed. Removing power is the only way to reset the 24LC22A 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 trans- mits the slave address consisting of a 7-bit device code (1010000) for the 24LC22A. The eighth bit of slave address determines whether the master device wants to read or write to the 24LC22A (Figure 3-7). The 24LC22A 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 24LC22A in the same way byte write. But instead of generating a Stop condition the master transmits up to eight data bytes to the 24LC22A, 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 DS21683B-page 10 Control Word Byte ...
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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 24LC22A to operate as a serial ROM, although this configuration would prevent using the device in the Transmit-Only mode. DS21683B-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 24LC22A 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 24LC22A discontinues transmission (Figure 7-2) ...
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... Serial Clock (VCLK) This pin is the clock input for the Transmit-Only mode (DDC1). In the Transmit-Only mode, each bit is clocked out on the rising edge of this signal. In the Bidirectional mode, a high logic level is required on this pin to enable write capability. 24LC22A S T Data ...
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... Standard marking consists of Microchip part number, year code, week code, traceability code (facility code, mask rev#, and assembly code). DS21683B-page 14 Example 24LC22A I/P 1L7 e 3 0145 Example 24LC22AI SN 0145 e 3 1L7 ) e 3 © 2007 Microchip Technology Inc. ...
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... N NOTE © 2007 Microchip Technology Inc 24LC22A c DS21683B-page 15 ...
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... N NOTE DS21683B-page φ α c β © 2007 Microchip Technology Inc. ...
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... Microchip Technology Inc. 24LC22A DS21683B-page 17 ...
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... APPENDIX A: REVISION HISTORY Revision A Original release of document. Revision B (10/2007) Revised Features (added Pb-free); Revised ambient temperature; Revised Table 1.1, Para. D8 and D9; Revised Packaging Information; Replaced Package Drawings; Replaced On-Line Support; Product ID System. DS21683B-page 18 Revised © 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 24LC22A should contact their distributor, DS21683B-page 19 ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Y Device: 24LC22A 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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... Package Plastic DIP (300 mil Body), 8-Lead SN = Plastic SOIC (3.90 mm Body), 8-Lead © 2007 Microchip Technology Inc. 24LC22A Examples: a) 24LC22A-I/P: Industrial temperature, PDIP package. b) 24LC22A-I/SN: Industrial temperature, SOIC package. c) 24LC22AT-I/SN: Tape and Reel, Industrial temperature, SOIC package. DS21683B-page21 ...
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... NOTES: DS21683B-page22 © 2007 Microchip Technology Inc. ...
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... Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights. © 2007 Microchip Technology Inc. Trademarks The Microchip name and logo, the Microchip logo, Accuron, dsPIC, K ...
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... 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 © 2007 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 ...