ds1841nt-r Maxim Integrated Products, Inc., ds1841nt-r Datasheet
ds1841nt-r
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ds1841nt-r Summary of contents
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Rev 1; 3/08 General Description The DS1841 is a 7-bit, logarithmic, nonvolatile (NV) digi- tal resistor that features an on-chip temperature sensor and associated analog-to-digital converter (ADC). The integrated temperature sensor indexes a 72-byte NV lookup table (LUT) encompassing a ...
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Temperature-Controlled, NV, I Logarithmic Resistor ABSOLUTE MAXIMUM RATINGS Voltage Range on SDA, SCL, and V Relative to GND .........................................-0.5V to +6.0V CC Voltage Range on RH, RW, A0, and A1 Relative to GND ................................-0. Operating Temperature Range .........................-40°C ...
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TEMPERATURE SENSOR CHARACTERISTICS (V = +2.7V to +5.5V -40°C to +100°C, unless otherwise noted PARAMETER SYMBOL Temperature Error Update Rate (Temperature and t Supply Conversion Time) ANALOG VOLTAGE MONITORING CHARACTERISTICS (V = +2.7V to +5.5V, T ...
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Temperature-Controlled, NV, I Logarithmic Resistor ELECTRICAL CHARACTERISTICS (See Figure 3) (continued +2.7V to +5.5V -40°C to +100°C, timing referenced PARAMETER SYMBOL EEPROM Write Time A0, A1 Setup Time ...
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T = +25°C, unless otherwise noted SUPPLY CURRENT vs. SUPPLY VOLTAGE 250 200 LUT MODE AND LUT ADDER MODE LUT MODE AND LUT ADDER MODE UPDATE MODE BIT = 1 UPDATE MODE BIT ...
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Temperature-Controlled, NV, I Logarithmic Resistor PIN NAME 2 1 SDA I C Serial Data. Input/output for I 2 GND Ground 3 V Power Supply Address Select Inputs. Determines I Slave Address Byte and Address Pins sections for ...
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LUT Adder Mode (Default) LUT Adder Mode is selected by setting the Update Mode bit to 1 and the Adder Mode bit to 1. This mode operates similar to LUT Mode with one major difference (see the LUT Mode and ...
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Temperature-Controlled, NV, I Logarithmic Resistor LUT Mode and LUT Adder Mode Block Diagram (Update Mode Bit = GND CONTROL SCL LOGIC/ REGISTERS SDA INTERFACE A0 A1 DATA TEMP SENSOR ADC VOLTAGE ...
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DECREASING LUT34 TEMPERATURE LUT33 LUT32 LUT31 TEMPERATURE LUT30 1°C HYSTERESIS WINDOW TEMPERATURE (°C) Figure 1. LUT Hysteresis MSB SLAVE ADDRESS* *THE SLAVE ADDRESS IS DETERMINED BY ADDRESS PINS A0, A1. Figure ...
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Temperature-Controlled, NV, I Logarithmic Resistor Memory Description The DS1841’s internal memory consists of both volatile and NV registers that are organized into eight byte Register 00h: Initial Value Register (IVR) FACTORY DEFAULT (IVR) 00h MEMORY TYPE NV MEMORY TYPE Volatile ...
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Register 03h: Control Register 1 (CR1) FACTORY DEFAULT 00h MEMORY TYPE Shadowed NV 03h Reserved Reserved Bit 7 Bits Reserved. Adder Mode This bit is valid only if the Update Mode bit = 1. Bit 1 0 ...
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Temperature-Controlled, NV, I Logarithmic Resistor Register 0Ah: Control Register 2 (CR2) FACTORY DEFAULT 00h MEMORY TYPE Volatile 0Ah Reserved Reserved Bit 7 Bits Reserved. Wiper Access Control This bit is valid only in LUT Mode and in ...
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Registers 80h to C7h: Temperature Lookup Register (LUT) FACTORY DEFAULT 00h MEMORY TYPE NV 80h to C7h Bit 7 These registers at location 80h to C7h are NV and serve to temperature compensate RW over the operating temperature range of ...
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Temperature-Controlled, NV, I Logarithmic Resistor SDA t BUF t LOW SCL t HD:STA STOP START NOTE: TIMING IS REFERENCE TO V AND V IL(MAX) IH(MIN) Figure Timing Diagram Byte read: A byte read is an 8-bit ...
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Writing multiple bytes to a slave multiple bytes can also be performed. During a sin- gle write sequence bytes in one page can be written at one time. If more than eight bytes are trans- ...
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Temperature-Controlled, NV, I Logarithmic Resistor tion, writes the slave address byte (R/W = 1), reads data with ACK or NACK as applicable, and generates a STOP condition. See Figure 4 for I Examples. Applications Information Power-Supply Decoupling To achieve the ...
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... Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 17 © 2008 Maxim Integrated Products Temperature-Controlled, NV, I Logarithmic Resistor DESCRIPTION is a registered trademark of Maxim Integrated Products, Inc Revision History PAGES CHANGED — ...