24C21 Catalyst Semiconductor, 24C21 Datasheet
24C21
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24C21 Summary of contents
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... SCL clock input, with both modes sharing a common SDA input/output (I/O). The transmit-only mode is a read-only mode, while the bi-directional mode is a read and write mode following the I mode the CAT24C21 features a 16-byte page write buffer. The device is available in 8-in DIP, SOIC, TSSOP, MSOP and TDFN packages. FUNCTIONAL SYMBOL ...
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ABSOLUTE MAXIMUM RATINGS* Temperature Under Bias .................. - +125 C Storage Temperature ........................ - +150 C Voltage on Any Pin with (1) Respect to Ground ............ -2 with Respect to Ground .............. ...
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A.C. CHARACTERISTICS 5.5 V, unless otherwise specified. Industrial temperature range ...
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... FUNCTIONAL DESCRIPTION The CAT24C21 has two modes of operation: 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 (VCLK and SCL respectively) and both modes sharing a common bi- directional data line (SDA) ...
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... The four most significant bits of the 8-bit slave address are fixed as 1010 for the CAT24C21 (see Fig. 8). The next three significant bits are "don't care". The last bit of the slave address specifies whether a Read or Write operation performed ...
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... START condition and its slave address. If the device has been selected along with a write operation, it responds with an ACK after receiving each 8-bit byte. When the CAT24C21 READ mode it transmits 8 bits of data, releases the SDA line, and monitors the line for an ACK. Once it receives this ACK, the CAT24C21 will continue to transmit data ...
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... Page Write The CAT24C21 writes bytes of data in a single write cycle, using the Page Write operation. The Page Write operation (Figure 10) is initiated in the same manner as the Byte Write operation, however instead of terminating after the initial word is transmitted, the Master is allowed to send up to fifteen additional bytes. ...
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... Master responds with an ACK, which tells the Slave that more data is being requested. The CAT24C21 will continue to output an 8-bit byte for each ACK sent by the Master. The entire memory content can thus be read out sequentially. If the end of memory is reached in the process, then addressing will 'wrap-around' to the beginning of memory ...
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Figure 11. Immediate Address Read Timing BUS ACTIVITY: MASTER SDA LINE SCL SDA Figure 12. Selective Read Timing BUS ACTIVITY: R MASTER ADDRESS T SDA LINE S Figure 13. Sequential Read Timing BUS ACTIVITY: SLAVE MASTER ADDRESS ...
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... ZD4: TDFN (3mm x 3mm, Lead free, Halogen free) *available upon request Notes: (1) The device used in the above example is a CAT24C21JI-TE13 (SOIC, Industrial Temperature, 2.5 Volt to 5.5 Volt Operating Voltage, Tape & Reel) (2) Product die revision letter is marked on top of the package as a suffix to the production date code (e.g., AYWWB). For additional information, please contact your Catalyst sales office ...
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REVISION HISTORY Date Rev. Reason 9/29/2003 H Replaced Block Diagram with Functional Symbol Eliminated commercial temperature range Updated marking 10/15/2003 I Added TDFN package Updated Pin Descriptions Updated DC Operating Characteristics Updated AC Characateristics Updated Byte Write Timing Figure Updated ...
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... Catalyst Semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Catalyst Semiconductor product could create a situation where personal injury or death may occur. ...