24LC21A-IP MicrochipTechnology, 24LC21A-IP Datasheet
24LC21A-IP
Related parts for 24LC21A-IP
24LC21A-IP 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 24LC21A is available in a standard 8-pin PDIP and SOIC package in both commercial and industrial temperature ranges. ...
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... ELECTRICAL CHARACTERISTICS 1.1 Maximum Ratings* V ........................................................................7.0V CC All inputs and outputs w.r.t. V .... -0. Storage temperature ..........................- +150 C Ambient temp. with power applied .....- +125 C Soldering temperature of leads (10 seconds) .. +300 C ESD protection on all pins * Notice: Stresses above those listed under “Maximum ratings” may cause perma- nent damage to the device ...
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... Schmitt trigger inputs which provide noise and spike specification for standard operation. I Preliminary 24LC21A Units Remarks kHz (Note 1) ns (Note 1) ns After this period the first clock ...
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... FUNCTIONAL DESCRIPTION The 24LC21A 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 and the Bi-directional 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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... The bus must be con- trolled by a master device that generates the Bi-direc- tional 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 2 C bus, device determines which mode is activated ...
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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 Bi-directional 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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... 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. ...
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... 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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... FIGURE 7-3: SEQUENTIAL READ BUS ACTIVITY MASTER DATA n CONTROL BYTE SDA LINE BUS ACTIVITY 8.0 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 Bi-direc- tional Mode. In the Transmit-Only Mode, which only allows data to be read from the device, data is also transferred on the SDA pin ...
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... NOTES: 1996 Microchip Technology Inc. Preliminary 24LC21A DS21160B-page 13 ...
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... NOTES: DS21160B-page 14 Preliminary 1996 Microchip Technology Inc. ...
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... Product Identification System To order or to obtain information (e.g., on pricing or delivery), please use the listed part numbers, and refer to the factory or the listed sales offices. 24LC21A — /P Package: Temperature Range: Device: 1996 Microchip Technology Inc Plastic DIP (300 mil Body), 8-lead ...
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W ORLDWIDE AMERICAS Corporate Office Microchip Technology Inc. 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 602 786-7200 Fax: 602 786-7277 Technical Support: 602 786-7627 Web: http://www.microchip.com Atlanta Microchip Technology Inc. 500 Sugar Mill Road, Suite 200B Atlanta, GA 30350 ...