AD7294BSUZ Analog Devices Inc, AD7294BSUZ Datasheet
AD7294BSUZ
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AD7294BSUZ Summary of contents
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FEATURES 12-bit SAR ADC with 3 μs conversion time 4 uncommitted analog inputs Differential/single-ended × V input ranges REF REF 2 high-side current sense inputs 59.4 V operating range 0.5% max gain error ±200 ...
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AD7294 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Revision History ............................................................................... 3 Functional Block Diagram .............................................................. 4 Specifications ..................................................................................... 5 DAC Specifications....................................................................... 5 ADC Specifications ...................................................................... 6 General Specifications ................................................................. 8 Timing Characteristics ................................................................ ...
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REVISION HISTORY 11/10—Rev Rev. F Change to Table 2, Dynamic Performance, Spurious-Free Dynamic Range (SFDR) ................................................................... 6 10/10—Rev Rev. E Change to Reflow Temperature, Table 5 ...................................... 10 5/10—Rev Rev. D Added 56-Lead LFCSP ...
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AD7294 FUNCTIONAL BLOCK DIAGRAM SENSE OVERRANGE V 10. SENSE OVERRANGE D1+ D2 D2– D1– AD7294 DV DD ...
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SPECIFICATIONS DAC SPECIFICATIONS 4 5.5 V, AGND = DGND = 0 V, internal 2.5 V reference otherwise noted. DAC OUTV+ AB and DAC OUTV 4 16.5 V, ...
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AD7294 ADC SPECIFICATIONS 4 5.5 V, AGND = DGND = −40°C to +105°C, unless otherwise noted. A Table 2. Parameter DC ACCURACY Resolution 1 Integral Nonlinearity (INL) ...
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Parameter TEMPERATURE SENSOR—INTERNAL Operating Range Accuracy Resolution Update Rate TEMPERATURE SENSOR—EXTERNAL Operating Range Accuracy Resolution Low Level Output Current Source 2 Medium Level Output Current Source High Level Output Current Source 2 Maximum Series Resistance (R ) for S External ...
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AD7294 GENERAL SPECIFICATIONS 4 5.5 V, AGND = DGND = DAC OUTV+ AB and DAC OUTV 4 16.5 V; OFFSET floating, therefore, ...
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TIMING CHARACTERISTICS Serial Interface 4 5.5 V, AGND = DGND = DAC OUTV+ AB and DAC OUTV 4 16.5 V; OFFSET IN ...
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AD7294 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted Table 5. Parameter Rating AGND −0 + AGND −0 DAC OUTV ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS REF /REF OUT CONNECT REF /REF OUT NOTES CONNECT. 2. CONNECT THE EXPOSED PAD TO THE GROUND PLANE OF THE PCB USING MULTIPLE VIAS ...
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AD7294 Table 7. Pin Function Descriptions TQFP Pin No. LFCSP Pin No 16, 17, 32 33, 59 14, 25, 56 13, 22, ...
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TQFP Pin No. LFCSP Pin No 43 46 Not applicable 49, 50, 51, 52 43, 44, 45 62, 63 55, ...
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AD7294 TYPICAL PERFORMANCE CHARACTERISTICS 20 8192 POINT FFT 5V, V RANGE DRIVE REF F = 22.22kSPS SAMPLE F = 10kHz 400kHz IN SCLK –20 SINGLE ENDED SNR = ...
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T = 25° 5V, 2V 0.8 DRIVE V = 2.5V REF 0.6 DD SINGLE-ENDED 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 256 768 1280 1792 2304 2816 0 512 1024 1536 2048 ...
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AD7294 1.5 1.0 MAX INL 0 DRIVE –0 SINGLE-ENDED 2 –1 MODE 400kHz –1.5 MIN INL –2.0 –2 REFERENCE VOLTAGE (V) Figure 17. ADC INL vs. Reference Voltage ...
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TIME (µs) Figure 23. Zoomed in Settling for a ¼ to ¾ Output Voltage Step 1.0 DAC A 0.9 DAC B DAC C ...
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AD7294 0 –0.2 –0.4 –0.6 –0.8 –1.0 –1.2 –1.4 –1.6 –1.8 –2.0 0 0.5 1.0 1.5 CAPACITANCE FROM D+ TO D– (nF) Figure 29. Temperature Error vs. Capacitor Between D+ and D− –5 –10 –15 –20 ...
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TERMINOLOGY DAC TERMINOLOGY Relative Accuracy For the DAC, relative accuracy or integral nonlinearity (INL measure of the maximum deviation, in LSBs, from a straight line passing through the endpoints of the DAC transfer function. Differential Nonlinearity Differential nonlinearity ...
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AD7294 THEORY OF OPERATION ADC OVERVIEW The AD7294 provides the user with a 9-channel multiplexer, an on-chip track-and-hold, and a successive approximation ADC based around a capacitive DAC. The analog input range for the part can be selected as a ...
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ADC. Figure 36 shows a typical connection diagram when operating the ADC in single-ended mode. +2.5V R +1.25V –1.25V R 1 ADDITIONAL PINS OMITTED FOR ...
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AD7294 2 × V p-p 220Ω REF 440Ω V+ GND 27Ω V– 220kΩ 220Ω 220Ω V+ 27Ω A V– 10kΩ 20kΩ 1 ADDITIONAL PINS OMITTED FOR CLARITY. Figure 38. Dual Op Amp Circuit to Convert a Single-Ended Bipolar Signal into ...
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Therefore, for an input voltage of ±200 mV at the pins, an output span of ±2 generated. The current sensors on the AD7294 are designed to remove any flicker noise and offset present in the sensed signal. ...
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AD7294 increased about the preset (V × 1.2)/12.5. If this occurs, the REF I OVERRANGE pin is set to a high logic level enabling SENSE appropriate action to be taken to prevent any damage to the external circuitry. The setpoint ...
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Series Resistance Cancellation The AD7294 has been designed to automatically cancel out the effect of parasitic, base, and collector resistance on the tempera- ture reading. This gives a more accurate result, without the need for any user characterization of the ...
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AD7294 This generates the 5 V output span from a 2.5 V reference. Digitally inverting the DAC allows the circuit to operate as a generic DAC when no offset is applied. If the offset pin is not being driven, it ...
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REGISTER SETTING The AD7294 contains internal registers (see Figure 49) that store conversion results, high and low conversion limits, and information to configure and control the device. COMMAND REGISTER RESULT REGISTER DAC REGISTERS T RESULT SENSE REGISTERS × 3 ALERT ...
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AD7294 COMMAND REGISTER (0x00) Writing in the command register puts the part into command mode. When in command mode, the part cycles through the selected channels from LSB (D0) to MSB (D7) on each subse- quent read (see Table 10). ...
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ADC Channel Allocation The three channel address bits indicate which channel the result in the result register represents. Table 13 details the channel ID bits (S.E. indicates single-ended and DIFF indicates differential). Table 13. ADC Channel Allocation Channel ID Function ...
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AD7294 DAC , DAC , DAC , DAC , REGISTERS (0x01 TO 0x04 Writing to these register addresses sets the DAC and DAC output voltage codes, respectively. Bits[D11:D0 the write result register are the ...
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CONFIGURATION REGISTER (0x09) The configuration register is a 16-bit read/write register that sets the operating modes of the AD7294. The bit functions of the configuration register are outlined in Table 23 and Table 24. On power-up, the configuration register is ...
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AD7294 POWER-DOWN REGISTER (0x0A) The power-down register is an 8-bit read/write register that powers down various sections on the AD7294 device. On power-up, the default value for the power-down register is 0x30. The content of the power-down register is provided ...
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T OFFSET REGISTERS (0x26 AND 0x27) SENSE The AD7294 has temperature offset, 8-bit twos complement regis- ters for both Remote Channel T 1 and Remote Channel T SENSE It allows the user to add or subtract an offset to the ...
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AD7294 I C INTERFACE 2 GENERAL TIMING Figure 50 shows the timing diagram for general read and write operations using C-compliant interface. The bus uses open-drain drivers; therefore, when no device ...
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SERIAL BUS ADDRESS BYTE The first byte the user writes to the device is the slave address byte. Similar to all I 2 C-compatible devices, the AD7294 has a 7-bit serial address. The 5 LSBs are user-programmable by the 3 ...
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AD7294 1 SCL SDA START BY MASTER SLAVE ADDRESS BYTE R ACK. BY AD7294 FRAME 1 ADDRESS POINTER REGISTER BYTE 1 SCL (CONTINUED) SDA (CONTINUED ...
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Writing Two Bytes of Data to a 16-Bit Register The limit and hysteresis registers (0x0B to 0x25), the result registers (0x01 to 0x04), and the configuration register (0x09) are 16-bit registers; therefore, two bytes of data are required to write ...
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AD7294 Reading Data from an 8-Bit Register Reading the contents from any of the 8-bit registers is a single byte read operation, as shown in Figure 55. In this protocol, the first part of the transaction writes to the register ...
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MODES OF OPERATION There are two different methods of initiating a conversion on the AD7294: command mode and autocycle mode. COMMAND MODE In command mode, the AD7294 ADC converts on-demand on either a single channel or a sequence of channels. ...
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AD7294 AUTOCYCLE MODE The AD7294 can be configured to convert continuously on a programmable sequence of channels making it the ideal mode of operation for system monitoring. These conversions take place in the background approximately every 50 µs, and are ...
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ALERTS AND LIMITS THEORY ALERT_FLAG BIT The alert_flag bit indicates whether the conversion result being read or any other channel result has violated the limit registers associated with it alert occurs and the alert_flag bit is set, the ...
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AD7294 The hysteresis register can be used to avoid flicker on the ALERT/ BUSY pin. If the hysteresis function is enabled, the conversion result must return to a value of at least N LSB below the DATA register value, or ...
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APPLICATIONS INFORMATION The AD7294 contains all the functions required for general- purpose monitoring and control of current, voltage, and temperature. With its 59.4 V maximum common-mode range, the device is useful in industrial and automotive applications where current sensing in ...
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AD7294 GAIN CONTROL OF POWER AMPLIFIER In gain control mode, a setpoint voltage, proportional the desired output power, is applied to a power detector such as the AD8362. A sample of the output power from the power ...
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LAYOUT AND CONFIGURATION POWER SUPPLY BYPASSING AND GROUNDING For optimum performance, carefully consider the power supply and ground return layout on any PCB where the AD7294 is used. The PCB containing the AD7294 should have separate analog and digital sections, ...
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AD7294 OUTLINE DIMENSIONS 1.05 1.00 0.95 0.15 SEATING 0.05 PLANE VIEW A ROTATED 90° CCW 8.00 BSC SQ PIN 1 INDICATOR TOP VIEW 1.00 12° MAX 0.85 0.80 SEATING PLANE 1.20 0.75 MAX 0.60 0. 0° MIN 0.20 ...
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... ORDERING GUIDE Model Temperature Range 1 AD7294BSUZ −40°C to +105°C AD7294BSUZRL −40°C to +105°C AD7294BCPZ −40°C to +105°C AD7294BCPZRL −40°C to +105°C EVAL-AD7294EBZ Z = RoHS Compliant Part. 1 Package Description 64-Lead Thin Plastic Quad Flat Package [TQFP] 64-Lead Thin Plastic Quad Flat Package [TQFP] ...
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AD7294 NOTES refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors). ©2008–2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05747-0-11/10(F) Rev ...