24lcs22a Microchip Technology Inc., 24lcs22a Datasheet
24lcs22a
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24lcs22a Summary of contents
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... SCL control byte is received, the device will revert to the Trans- mit-Only mode after it receives 128 consecutive VCLK pulses while the SCL pin is idle. The 24LCS22A is avail- able in standard 8-pin PDIP and SOIC packages. The 24LCS22A features a flexible Write-Protect pin which is enabled by writing to address 7Fh (usually the checksum ® ...
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... ELECTRICAL CHARACTERISTICS (†) Absolute Maximum Ratings V .............................................................................................................................................................................7.0V CC All inputs and outputs w.r.t. V ......................................................................................................... -0. Storage temperature ...............................................................................................................................- +150 C Ambient temperature with power applied ................................................................................................- +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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... Units Conditions kHz 2.5V V 5.5V CC 4. 2.5V V 5.5V CC 4. 2.5V V 5.5V CC 4. 2.5V V 5.5V (Note ...
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... FUNCTIONAL DESCRIPTION The 24LCS22A 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 oper- ates 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 clock (SCL), controls access to the bus and generates the Start and Stop conditions, while the 24LCS22A 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 24LCS22A 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 24LCS22A 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 24LCS22A. ...
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... Note: Once switched into Bidirectional mode, the 24LCS22A will remain in that mode until power is removed. Removing power is the only way to reset the 24LCS22A 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 24LCS22A. The eighth bit of slave address determines whether the master device wants to read or write to the 24LCS22A (Figure 3-7). The 24LCS22A 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 24LCS22A in the same way byte write. But instead of generating a Stop condition the master transmits up to eight data bytes to the 24LCS22A 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 DS21682C-page 10 Control Word Byte Address STA SU STO S T Data SPVL © 2005 Microchip Technology Inc. ...
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... Microchip Technology Inc. FIGURE 5-1: Write Command Initiate Write Cycle Send Control Byte Word Data Address Data ( 24LCS22A ACKNOWLEDGE POLLING FLOW Send Send Stop Condition to Send Start with R Did Device Acknowledge (ACK = 0)? Yes Next Operation ...
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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 24LCS22A 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 24LCS22A discontinues transmission (Figure 7-2) ...
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... Sequential Read Sequential reads are initiated in the same way as a random read except that after the 24LCS22A transmits the first data byte, the master issues an acknowledge as opposed to a Stop condition in a random read. This directs the 24LCS22A to transmit the next sequentially addressed 8-bit word (Figure 7-3) ...
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... Internal Connection 8.1 Write -Protect (WP) This pin is used for flexible write protection of the 24LCS22A. When memory location 7Fh is written with any data, this pin is enabled and determines the write capability of the 24LCS22A (Table 6-1). 8.2 Serial Address/Data Input/Output (SDA) This pin is used to transfer addresses and data into and out of the device, when the device is in the Bidirectional mode ...
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... Standard marking consists of Microchip part number, year code, week code, traceability code (facility code, mask rev#, and assembly code). © 2005 Microchip Technology Inc. 24LCS22A Example: 24LCS22A I/PNNN 0145 Example: 24LCS22A I/SN0145 NNN DS21682C-page 15 ...
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... Plastic Dual In-line (P) – 300 mil (PDIP Dimension Limits Number of Pins Pitch Top to Seating Plane Molded Package Thickness Base to Seating Plane Shoulder to Shoulder Width Molded Package Width Overall Length Tip to Seating Plane Lead Thickness Upper Lead Width ...
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... A1 E .228 .237 .244 E1 .146 .154 .157 D .189 .193 .197 h .010 .015 .020 L .019 .025 .030 .008 .009 .010 B .013 .017 .020 24LCS22A A2 MILLIMETERS MIN NOM MAX 8 1.27 1.35 1.55 1.75 1.32 1.42 1.55 0.10 0.18 0.25 5.79 6.02 6.20 3.71 3.91 3.99 4.80 4.90 5.00 0.25 0.38 0.51 0.48 0.62 0. 0.20 0.23 0.25 0.33 0.42 0. ...
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... APPENDIX A: REVISION HISTORY Revision B Corrections to Section 1.0, Electrical Characteristics. Revision C Revised Section 8.1. Added new package legend. DS21682C-page 18 © 2005 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 24LCS22A should contact their distributor, DS21682C-page 19 ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Y Device: 24LCS22A 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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... To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office PART NO. X /XX Device Temperature Package Range Device: 24LCS22A: 2K VESA E-EDID Serial EEPROM 24LCS22AT: 2K VESA E-EDID Serial EEPROM (Tape and Reel) Temperature Range -40°C to +85°C Package Plastic DIP (300 mil Body), 8-Lead ...
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... NOTES: DS21682C-page 22 © 2005 Microchip Technology Inc. ...
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... Use of Microchip’s products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights. © 2005 Microchip Technology Inc. Trademarks The Microchip name and logo, the Microchip logo, Accuron, dsPIC ...
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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 © 2005 Microchip Technology Inc. EUROPE Austria - Wels Tel: 43-7242-2244-399 Fax: 43-7242-2244-393 Denmark - Copenhagen Tel: 45-4450-2828 Fax: 45-4485-2829 France - Paris ...