AD5245 Analog Devices, AD5245 Datasheet
AD5245
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AD5245 Summary of contents
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... RF amplifier biasing Automotive electronics adjustment Gain control and offset adjustment GENERAL OVERVIEW The AD5245 provides a compact 2.9 mm × packaged solution for 256-position adjustment applications. These devices perform the same electronic adjustment function as mechanical potentiometers or variable resistors, with enhanced resolution, solid-state reliability, and superior low temperature coefficient performance ...
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... AD5245 TABLE OF CONTENTS Electrical Characteristics—5 kΩ Version ...................................... 3 Electrical Characteristics—10 kΩ, 50 kΩ, 100 kΩ Versions ....... 4 Timing Characteristics—5 kΩ, 10 kΩ, 50 kΩ, 100 kΩ Versions 5 Absolute Maximum Ratings............................................................ 5 Typical Performance Characteristics ............................................. 6 Test Circuits..................................................................................... Interface..................................................................................... 11 Operation......................................................................................... 12 Programming the Variable Resistor ......................................... 12 Programming the Potentiometer Divider ...
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... GND 0. 2.4 0.8 2.1 0.6 ±1 5 2.7 5 0.2 DD ±0.02 ±0.05 1 kHz 0. AD5245 Unit LSB LSB % ppm/°C Ω Bits LSB LSB ppm/°C LSB LSB µ µ µA mW %/% MHz % µs nV/√Hz ...
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... AD5245 ELECTRICAL CHARACTERISTICS—10 kΩ, 50 kΩ, 100 kΩ VERSIONS ( ± 10 ± 10 Table 2. Parameter DC CHARACTERISTICS—RHEOSTAT MODE 2 Resistor Differential Nonlinearity 2 Resistor Integral Nonlinearity 3 Nominal Resistor Tolerance Resistance Temperature Coefficient Wiper Resistance DC CHARACTERISTICS—POTENTIOMETER DIVIDER MODE (Specifications apply to all VRs) ...
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... Exposure to absolute maximum rating conditions for extended periods may affect device reliability. –40°C to +125°C 150°C –65°C to +150°C 300°C 230°C/W Rev Page AD5245 1 Min Typ Max Unit 400 kHz 1.3 µs 0.6 µ ...
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... AD5245 TYPICAL PERFORMANCE CHARACTERISTICS 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1 128 160 CODE (Decimal) Figure 3. R-INL vs. Code vs. Supply Voltages 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1 128 CODE (Decimal) Figure 4. R-DNL vs. Code vs. Supply Voltages 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1 ...
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... Rev Page 5. 2. TEMPERATURE (°C) Figure 12. Zero-Scale Error vs. Temperature TEMPERATURE (°C) Figure 13. Supply Current vs. Temperature TEMPERATURE (°C) Figure 14. Shutdown Current vs. Temperature AD5245 120 120 120 120 ...
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... AD5245 200 150 100 50 0 – 128 CODE (Decimal) Figure 15. Rheostat Mode Tempco ∆R 160 140 120 100 – 128 160 CODE (Decimal) Figure 16. Potentiometer Mode Tempco ∆V REF LEVEL /DIV MARKER 1 000 000.000Hz 0.000dB 6 ...
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... 100ns A CH2 3. Figure 24. Digital Feedthrough 100mV 200ns A CH1 152mV Figure 25. Midscale Glitch, Code 0x80–0x7F 5.00V 200ns A CH1 3. AD5245 VW SCL VW SCL VW SCL ...
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... AD5245 TEST CIRCUITS Figure 27 to Figure 35 illustrate the test circuits that define the test conditions used in the product specification tables. DUT 1LSB = V+/ Figure 27. Test Circuit for Potentiometer Divider Nonlinearity Error (INL, DNL) NO CONNECT DUT Figure 28. Test Circuit for Resistor Position Nonlinearity Error (Rheostat Operation ...
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... Data Byte ACK BY AD5245 FRAME 3 DATA BYTE ACK BY MASTER FRAME 2 STOP BY RDAC REGISTER MASTER AD5245 ACK BY AD5245 STOP BY MASTER ...
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... AD5245 OPERATION The AD5245 is a 256-position digitally controlled variable resistor (VR) device. An internal power-on preset places the wiper at midscale during power-on, which simplifies the fault condition recovery at power-up. PROGRAMMING THE VARIABLE RESISTOR Rheostat Operation The nominal resistance of the RDAC between terminals A and B is available in 5 kΩ ...
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... I C COMPATIBLE 2-WIRE SERIAL BUS The first byte of the AD5245 is a slave address byte (see Table 5 and Table 6). It has a 7-bit slave address and bit. The six MSBs of the slave address are 010110, and the following bit is determined by the state of the AD0 pin of the device. AD0 allows the user to place up to two of the I on one bus ...
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... Similarly, a repeated read function of the RDAC is also allowed. Readback RDAC Value The AD5245 allows the user to read back the RDAC values in the read mode. Refer to Table 5 and Table 6 for the programming format. Multiple Devices on One Bus Figure 40 shows two AD5245 devices on the same serial bus ...
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... F AD5245 Figure 45. Power Supply Bypassing Name Description W W Terminal. V Positive Power Supply. DD GND Digital Ground. SCL Serial Clock Input. Positive edge triggered. SDA Serial Data Input/Output. AD0 Programmable address bit 0 for multiple package decoding Terminal Terminal. AD5245 GND ...
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... See Note 1 1 The evaluation board is shipped with the 10 kΩ R The AD5245 contains 2532 transistors. Die size: 30.7 mil × 76.8 mil = 2,358 sq. mil. ESD CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges ...