24LC21 MicrochipTechnology, 24LC21 Datasheet
24LC21
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24LC21 Summary of contents
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... Industrial (I): -40˚C to +85˚C DESCRIPTION The Microchip Technology Inc. 24LC21 is a 128 x 8 bit Electrically Erasable PROM. This device is designed for use in applications requiring storage and serial trans- mission of configuration and control information. Two modes of operation have been implemented: Transmit Only Mode and Bi-Directional Mode ...
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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 ..................................... -65˚C to +150˚C Ambient temp. with power applied ................ -65˚C to +125˚C Soldering temperature of leads (10 seconds) ............. +300˚C ESD protection on all pins *Notice: Stresses above those listed under “Maximum ratings” ...
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... Schmitt trigger inputs which provide improved specification for standard operation. I 24LC21 Units Remarks kHz (Note 1) ns (Note 1) ns After this period the first clock pulse is generated ...
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... FUNCTIONAL DESCRIPTION The 24LC21 operates in two modes, the Transmit-Only Mode and the Bi-Directional Mode. There is a separate two wire protocol to support each mode, each having a separate clock input and sharing a common data line (SDA). The device enters the Transmit-Only Mode upon power-up ...
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... Bi-Direc- tional Mode Clock (SCL), controls access to the bus and generates the START and STOP conditions, while the 24LC21 acts as the slave. Both master and slave can operate as transmitter or receiver, but the master device determines which mode is activated. ...
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... The master device must generate an extra clock pulse which is associated with this acknowledge bit. Note: The 24LC21 does not generate any acknowledge bits if an internal program- ming cycle is in progress. The device that acknowledges has to pull down the ...
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... A 4.2 Page Write The write control byte, word address and the first data byte are transmitted to the 24LC21 in the same way byte write. But instead of generating a stop condi- X tion the master transmits up to eight data bytes to the 24LC21 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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... VCLK pin operates as the write protect control pin. Set- ting VCLK high allows normal write operations, while setting VCLK low prevents writing to any location in the array. Connecting the VCLK pin to V 24LC21 to operate as a serial ROM, although this con- figuration would prevent using the device in the Trans- mit-Only Mode. S ...
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... Microchip Technology Inc. set. Then the master issues the control byte again but with the R/W bit set to a one. The 24LC21 will then issue an acknowledge and transmits the eight bit data word. The master will not acknowledge the transfer but does generate a stop condition and the 24LC21 discon- tinues transmission (Figure 7-2) ...
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... FIGURE 7-3: SEQUENTIAL READ BUS ACTIVITY CONTROL MASTER BYTE DATA n SDA LINE A C BUS ACTIVITY K 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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... 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. 24LC21 - /P Package: Temperature Range: Device: 1996 Microchip Technology Inc Plastic DIP (300 mil Body), 8-lead SN = Plastic SOIC (150 mil Body), 8-lead Blank = 0˚ ...
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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 ...