DS2745U+ Maxim Integrated Products, DS2745U+ Datasheet
DS2745U+
Specifications of DS2745U+
Related parts for DS2745U+
DS2745U+ Summary of contents
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... DS2745. A low-power sleep mode state conserves energy when the cell pack is in storage. APPLICATIONS Cellular GPS PDAs Handheld Products MARKING MAX package 2745 2745 DS2745U+ in Tape-and-Reel DS2745 2 Low-Cost I C Battery Monitor VDD SCL 8 1 VIN SDA 2 ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on All Pins Relative to V Operating Temperature Range Storage Temperature Range Soldering Temperature * This is a stress rating only and functional operation of the device at these or any other conditions above those indicated ...
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Input Resistance, VIN Input Logic High: SCL, SDA, PIO Input Logic Low: SCL, SDA, PIO Output Logic Low: SDA, PIO Pulldown Current: SCL, SDA, PIO Input Capacitance: SCL, C SDA SLEEP Timeout t SLEEP 2-WIRE INTERFACE TIMING SPECIFICATIONS (V = ...
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All voltages are referenced to V Note 1: Offset specified after auto-calibration cycle and Current Offset Bias register (COBR) set to 00h. Note 2: To properly enter sleep mode, SMOD=1, and the application should hold SDA and SCL low for ...
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PIN DESCRIPTION PIN SYMBOL 1 SCL 2 SDA 3 PIO 4 SNS CTG 7 VIN Figure 2. BLOCK DIAGRAM Serial Clock Input. 2-Wire clock line. Input only. Connect this pin to the CLOCK ...
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... C interface, the DS2745 allows a host system read/write access to the Status, Configuration and Measurement registers. Additionally, the I Figure 3. APPLICATION EXAMPLE 1 Cell Li+ Protection IC (Li+/Polymer) 102 102 FuelPack is a trademark of Maxim Integrated Products, Inc slave address can be changed from the default after power up. 500 1k DS2745 PIO CTG ...
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POWER MODES The DS2745 operates in one of two power modes: active and sleep. While in active mode, the DS2745 operates as a high-precision battery monitor with voltage, temperature, current and accumulated current measurements acquired continuously and the resulting values ...
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Figure 5. TEMPERATURE REGISTER FORMAT MSB—Address MSb “S”: sign bit, “X”: reserved CURRENT MEASUREMENT In the active mode of operation, the DS2745 continually measures the current flow into and out of the ...
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CURRENT ACCUMULATION The Accumulated Current register (ACR) serves as an up/down counter holding a running count of charge stored in the battery. Current measurement results, plus a programmable bias value are internally summed, or accumulated, at the completion of each ...
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CURRENT BLANKING The Current Blanking feature modifies current measurement result prior to being accumulated in the ACR. Current Blanking occurs conditionally when a current measurement (raw current + COBR) falls in one of two defined ranges. The first range prevents ...
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Table 5. MEMORY MAP ADDRESS (HEX) 00 Reserved 01 Status/Config Register Reserved Reserved 0A Temperature Register MSB 0B Temperature Register LSB 0C Voltage Register MSB 0D Voltage Register LSB 0E Current Register MSB 0F ...
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BUS SYSTEM The 2-Wire bus system supports operation as a slave only device in a single or multi-slave, and single or multi- master system 128 slave devices may share the bus by uniquely setting the 7-bit slave ...
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Read/Write Bit The R/W bit following the slave address determines the data direction of subsequent bytes in the transfer. R selects a write transaction, with the following bytes being written by the master to the slave. R/W = ...
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Write Data Protocol The write data protocol is used to write to register and shadow RAM data to the DS2745 starting at memory address MAddr. Data0 represents the data written to MAddr, Data1 represents the data written to MAddr + ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time Maxim is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Maxim Integrated Products, Inc DESCRIPTION maximum operating range in the Electrical Characteristics voltage” ...