AD7156BCPZ-REEL7 Analog Devices Inc, AD7156BCPZ-REEL7 Datasheet
AD7156BCPZ-REEL7
Specifications of AD7156BCPZ-REEL7
Related parts for AD7156BCPZ-REEL7
AD7156BCPZ-REEL7 Summary of contents
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FEATURES Ultralow power Power supply voltage: 1 3.6 V Operation power supply current: 70 μA typical Power-down current: 2 μA typical Fast response time Conversion time per channel Wake-up time from serial interface: 300 μs Adaptive ...
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AD7156 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Timing Specifications .................................................................. 5 Absolute Maximum Ratings ............................................................ 6 ESD Caution .................................................................................. 6 Pin ...
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SPECIFICATIONS 3.6 V, GND = 0 V, temperature range = −40°C to +85°C, unless otherwise noted. DD Table 1. Parameter CAPACITIVE INPUT 2, 3 Conversion Input Range, CIN to EXC 4, 5 Resolution Maximum Allowed ...
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AD7156 Parameter POWER REQUIREMENTS V -to-GND Voltage Current DD I Current Power-Down Mode −12 −15 Capacitance units × The CAPDAC can ...
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TIMING SPECIFICATIONS 3.6 V, GND = 0 V, Input Logic Input Logic Table 2. Parameter CONVERTER 1 Conversion Time Wake-Up Time from Power-Down Mode 2, 4 Power-Up ...
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AD7156 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter Positive Supply Voltage V to GND DD Voltage on Any Input or Output to GND ESD Rating ESD Association Human Body Model, S5.1 Field-Inducted Charged Device ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 GND Ground Pin. Power Supply Voltage. This pin should be decoupled to GND using a low impedance capacitor, such VDD 0.1 μF ...
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AD7156 TYPICAL PERFORMANCE CHARACTERISTICS 2.0 1.8 1.6 1.4 1.2 1.8V 1.0 0.8 0.6 0.4 0 100 150 CAPACITANCE CIN TO GROUND (pF) Figure 4. Capacitance Input Offset Error vs. Capacitance CIN to GND 1.8 V ...
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RESISTANCE CIN TO GND (MΩ) Figure 10. Capacitance Input Gain Error vs. Resistance CIN to GND 1.8 V and 3.3 V, CIN to EXC = 3 ...
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AD7156 –1 –2 –3 –4 –5 –50 – TEMPERATURE (°C) Figure 16. Capacitance Input Offset Error vs. Temperature 1.8 V and 3.3 V, CIN and EXC Pins Open Circuit DD ...
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THEORY OF OPERATION AD7156 CIN1 C X1 EXC1 MUX CIN2 C X2 EXC2 The AD7156 core is a high performance capacitance-to-digital converter (CDC) that allows the part to be interfaced directly to a capacitive sensor. The comparators compare the CDC ...
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AD7156 COMPARATOR AND THRESHOLD MODES The AD7156 comparators and their thresholds can be programmed to operate in two modes: fixed and adaptive threshold modes adaptive mode, the threshold is dynamically adjusted and the comparator output indicates fast changes ...
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DATA AVERAGE The adaptive threshold algorithm is based on an average calculated from the previous CDC output data, using the following equation: Data ( N = − + Average ( N ) Average ( where: Average(N) is ...
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AD7156 AUTO-DAC ADJUSTMENT In adaptive threshold mode, the part can dynamically adjust the CAPDAC to keep the CDC in an optimal operating capacitive range. When the auto-DAC function is enabled, the CAPDAC value is automatically incremented when the data average ...
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REGISTER DESCRIPTIONS 1 Table 5. Register Summary Addr Pointer Register Dec Hex Status 0 0x00 Ch 1 Data High 1 0x01 Ch 1 Data Low 2 0x02 Ch 2 Data High 3 0x03 Ch 2 Data Low 4 0x04 Ch ...
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AD7156 STATUS REGISTER Address Pointer 0x00 8 Bits, Read Only Default Value 0x53 Before Conversion, 0x54 After Conversion The status register indicates the status of the part. The register can be read via the 2-wire serial interface to query the ...
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DATA REGISTERS Ch 1 Address Pointer 0x01, Address Pointer 0x02 Ch 2 Address Pointer 0x03, Address Pointer 0x04 16 Bits, Read Only Default Value 0x0000 Data from the last complete capacitance-to-digital conversion reflects the capacitance on the input. Only the ...
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AD7156 AVERAGE REGISTERS Ch 1 Address Pointer 0x05, Address Pointer 0x06 Ch 2 Address Pointer 0x07, Address Pointer 0x08 16 Bits, Read Only Default Value 0x0000 These registers show the average calculated from the previous CDC data. The 12-bit CDC ...
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SETUP REGISTERS Ch 1 Address Pointer 0x0B Ch 2 Address Pointer 0x0E 8 Bits, Read/Write, Factory Preset 0x0B 1 Table 10. Setup Registers Bit Map Bit 7 Bit 6 RngH RngL (0) (0) 1 The default values are given in ...
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AD7156 CONFIGURATION REGISTER Address Pointer 0x0F 8 Bits, Read/Write, Factory Preset 0x19 Table 12. Configuration Register Bit Map Bit 7 Bit 6 ThrFixed ThrMD1 (0) (0) 1 The default values are given in parentheses. Table 13.Configuration Register Bit Descriptions Bit ...
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POWER-DOWN TIMER REGISTER Address Pointer 0x10 8 Bits, Read/Write, Factory Preset 0x40 Table 14. Power-Down Timer Register Bit Map Bit 7 Bit 6 (0) (1) 1 The default values are given in parentheses. Table 15.Power-Down Timer Register Bit Descriptions Bit ...
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AD7156 SERIAL INTERFACE 2 The AD7156 supports an I C-compatible, 2-wire serial inter- face. The two wires on the serial bus (interface) are called SCL (clock) and SDA (data). These two wires carry all addressing, control, and data information one ...
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If a repeated start condition is encountered after the address pointer byte, all peripherals connected to the bus respond exactly as outlined previously for a start condition; that is, a repeated start condition is treated the same as a start ...
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AD7156 HARDWARE DESIGN CONSIDERATIONS OVERVIEW The AD7156 is an interface to capacitive sensors. On the input side, Sensor C can be connected directly between X the AD7156 EXC and CIN pins. The way it is connected and the electrical parameters ...
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PARASITIC SERIAL RESISTANCE R S1 CIN EXC Figure 45. Parasitic Serial Resistance The AD7156 CDC result is affected by a resistance in series with the measured capacitance. The total serial resistance ( Figure ...
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AD7156 APPLICATION EXAMPLES SENS1 EXC1 C SENS2 EXC2 39kΩ 82kΩ 68pF 22pF C SENS1 10kΩ 47pF 39kΩ 82kΩ 68pF 22pF C SENS2 10kΩ 47pF 0.1µF 1kΩ VDD AD7156 CIN1 SDA SCL SENS1 EXC1 OUT1 CIN2 OUT2 1kΩ ...
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... OUTLINE DIMENSIONS PIN 1 INDEX AREA 0.80 0.75 0.70 SEATING PLANE ORDERING GUIDE Model Temperature Range AD7156BCPZ-REEL 1 −40°C to +85°C 1 AD7156BCPZ-REEL7 −40°C to +85°C EVAL-AD7156EBZ RoHS Compliant Part. 0.30 3.00 0.23 BSC SQ 0. EXPOSED (BOTTOM VIEW) 0.50 0.40 5 0.30 TOP VIEW ...
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AD7156 NOTES Purchase of licensed components of Analog Devices or one of its sublicensed Associated Companies conveys a license for the purchaser under the Philips I 2 Rights to use these components system, ...