Datasheet

DS2438
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NOTES:
1. Temperature conversion takes up to 10 ms.
2. A/D conversion takes up to 4 ms.
3. EEPROM writes take up to 10 ms.
SAMPLE COMMAND SEQUENCE Table 12
Example: Bus Master enables the ICA, CCA, and DCA on a single DS2438 and configures it such that
the CCA/DCA information is shadowed to EEPROM. The voltage A/D is configured such that the
DS2438 will perform voltage measurements on the battery (VDD) voltage.
MASTER MODE DATA (LSB FIRST) COMMENTS
TX Reset Read pulse
RX Presence Presence pulse
TX CCh Skip ROM
TX 4Eh00h Issue Write SP 00h command
TX 0Fh Sets ICA, CA, EE, AD Bits active
TX Reset Reset pulse
RX Presence Presence pulse
TX CCh Skip ROM
TX BEh00h Issue Read SP 00h command
RX <9 data bytes> Read scratchpad data and CRC
TX Reset Reset pulse
RX Presence Presence pulse
TX CCh Skip ROM
TX 48h00h Issue Copy SP 00h command
RX Read Slots DS2438 returns a “1” when Copy SP is complete
TX Reset Reset pulse
RX Presence Presence Pulse, done