EVAL-AD7150EBZ Analog Devices Inc, EVAL-AD7150EBZ Datasheet
EVAL-AD7150EBZ
Specifications of EVAL-AD7150EBZ
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EVAL-AD7150EBZ Summary of contents
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FEATURES Ultra-low power 2 3.6 V, 100 μA Response time Adaptive environmental compensation 2 independent capacitance input channels Sensor capacitance ( SENS Sensitivity EMC tested 2 ...
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AD7150 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications .................................................................. 4 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. ...
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SPECIFICATIONS 3.6 V; GND = 0 V; –40°C to +85°C, unless otherwise noted. DD Table 1. Parameter CAPACITIVE INPUT 2 Conversion Input Range CIN to EXC 3 Resolution 3 Allowed Capacitance CIN to GND 3 ...
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AD7150 Parameter POWER REQUIREMENTS V -to-GND Voltage Current Current Power-Down Mode DD 1 Capacitance units: one picofarad (1 pF × The CAPDAC can be used to shift (offset) the input ...
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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 HBM (ESD Association Human Body Model, S5.1) ESD Rating FICDM ...
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AD7150 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 GND Ground Pin. 2 VDD Power Supply Voltage. This pin should be decoupled to GND using a low impedance capacitor, for example, 0.1 μF ...
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TYPICAL PERFORMANCE CHARACTERISTICS 300 200 100 0 –100 0 50 100 150 CAPACITANCE CIN TO GND (pF) Figure 4. Capacitance Input Offset Error vs. Capacitance CIN to GND 3.3 V, EXC Pin Open Circuit –2 ...
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AD7150 500 250 0 –250 –500 1 10 RESISTANCE CIN TO GND (MΩ) Figure 10. Capacitance Input Offset Error vs. Resistance CIN to GND 3.3 V, EXC Pin Open Circuit –5 – ...
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TEMPERATURE (°C) Figure 16. Capacitance Input Offset Error vs. Temperature 3.3 V, CIN and EXC Pins Open Circuit DD 0.2 0.1 0 –0.1 –0.2 –50 – ...
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AD7150 ARCHITECTURE AND MAIN FEATURES AD7150 CIN1 C X1 EXC1 MUX CIN2 C X2 EXC2 The AD7150 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 ...
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COMPARATOR AND THRESHOLD MODES The AD7150 comparators and their thresholds can be programmed to operate in several different modes adaptive mode, the threshold is dynamically adjusted and the comparator output indicates fast changes and ignores slow changes in ...
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AD7150 SENSITIVITY In adaptive threshold mode, the output comparator threshold is set as a defined distance (sensitivity) above the data average, below the data average, or both, depending on the selected threshold mode of operation (see Figure 31). The sensitivity ...
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AUTOCAPDAC ADJUSTMENT In adaptive threshold mode, the part can dynamically adjust the CAPDAC to keep the CDC in an optimal operating capacitive range. When the AutoDAC function is enabled, the CAPDAC value is automatically incremented when the data average exceeds ...
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AD7150 REGISTER DESCRIPTIONS Table 5. Register Summary Pointer Register (Dec) (Hex) R/W Status 0 0x00 R Ch1 Data High 1 0x01 R Ch1 Data Low 2 0x02 R Ch2 Data High 3 0x03 R Ch2 Data Low 4 0x04 R ...
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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 status of ...
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AD7150 DATA REGISTERS Ch1 Address Pointer 0x01, 0x02 Ch2 Address Pointer 0x03,0x04 16 Bits, Read-Only, Default Value 0x0000 Data from the last complete capacitance-to-digital conversion reflects the capacitance on the input. Only the 12 MSBs (most significant bits) of the ...
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TIMEOUT REGISTERS Ch1 Address Pointer 0x0A Ch2 Address Pointer 0x0D 8 Bits, Read/Write, Factory Preset 0x86 Table 9. Timeout Register Bit Map Bit Bits [7:4] Mnemonic TimeOutApr Default 0x08 These registers set timeouts for the adaptive threshold mode. The approaching ...
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AD7150 SETUP REGISTERS Ch1 Address Pointer 0x0B Ch2 Address Pointer 0x0E 8 Bits, Read/Write, Factory Preset 0x0B Table 10. Setup Registers Bit Map Bit Bit 7 Mnemonic RngH Default 0 Table 11. Setup Registers Bit Descriptions Bit Mnemonic Description 7 ...
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CONFIGURATION REGISTER Address Pointer 0x0F 8 Bits, Read/Write, Factory Preset 0x19 Table 12. Configuration Register Bit Map Bit Bit 7 Mnemonic ThrFixed Default 0 Table 13.Configuration Register Bit Descriptions Bit Mnemonic Description 7 ThrFixed ThrFixed = 1 sets the fixed ...
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AD7150 POWER-DOWN TIMER REGISTER Address Pointer 0x10 8 Bits, Read/Write, Factory Preset 0x00 Table 14. Power-Down Timer Register Bit Map Bit Bit 7 Mnemonic – Default 0 Table 15.Power-Down Timer Register Bit Descriptions Bit Mnemonic Description [7:6] – These bits ...
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SERIAL INTERFACE 2 The AD7150 supports an I C-compatible, 2-wire serial interface. 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 bit at ...
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AD7150 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 ...
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HARDWARE DESIGN CONSIDERATIONS OVERVIEW The AD7150 is an interface to capacitive sensors. On the input side, the sensor (C ) can be connected directly X between the AD7150 EXC and CIN pins. The way it is connected and the electrical ...
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AD7150 PARASITIC SERIAL RESISTANCE R S1 CIN EXC Figure 47. Parasitic Serial Resistance The AD7150 CDC result is affected by a resistance in series with the measured capacitance. The total serial resistance ( Figure ...
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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 AD7150 CIN1 SDA SCL SENS1 EXC1 OUT1 CIN2 OUT2 1kΩ SENS2 ...
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AD7150 OUTLINE DIMENSIONS ORDERING GUIDE Model Temperature Range 1 AD7150BRMZ −40°C to +85°C 1 AD7150BRMZ-REEL −40°C to +85° RoHS Compliant Part. 3.10 3.00 2. 5.15 3.10 4.90 3.00 4.65 2. PIN 1 0.50 ...
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NOTES Rev Page AD7150 ...
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AD7150 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, ...