AD7811 Analog Devices, AD7811 Datasheet
AD7811
Specifications of AD7811
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AD7811 Summary of contents
Page 1
... The AD7811 is available in a small, 16-lead 0.3" wide, plastic dual-in-line package (mini-DIP 16-lead 0.15" wide, Small Outline IC (SOIC) and in a 16-lead, Thin Shrink Small Out- line Package (TSSOP). The AD7812 is available in a small, 20-lead 0.3" ...
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... AD7811/AD7812–SPECIFICATIONS Parameter DYNAMIC PERFORMANCE Signal to (Noise + Distortion) Ratio Total Harmonic Distortion (THD) 1 Peak Harmonic or Spurious Noise 1, 2 Intermodulation Distortion Second Order Terms Third Order Terms 1, 2 Channel-to-Channel Isolation DC ACCURACY Resolution Minimum Resolution for Which No Missing Codes are Guaranteed 1 Relative Accuracy ...
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... [EXT] unless otherwise noted) DD REF DD Unit Conditions/Comments µs (max) Power-Up Time of AD7811/AD7812 after Rising Edge of CONVST µs (max) Conversion Time CONVST Pulsewidth ns (min) ns (min) SCLK High Pulsewidth ns (min) SCLK Low Pulsewidth ns (min) RFS Rising Edge to SCLK Rising Edge Setup Time ...
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... Digital Input Voltage to DGND (CONVST, SCLK, RFS, TFS, DIN, A0 –0 Digital Output Voltage to DGND (DOUT –0 REF to AGND . . . . . . . . . . . . . . . . . . . –0 Analog Inputs V –V (AD7811 –0 IN1 IN4 V –V (AD7812 –0 IN1 IN8 Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C Plastic DIP Package, Power Dissipation . . . . . . . . . . 450 mW θ ...
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... Serial Interface section. Serial Clock Input. An external serial clock is applied to this input to obtain serial data from the AD7811/AD7812 and also to latch data into the AD7811/AD7812. Data is clocked out on the rising edge of SCLK and latched in on the falling edge of SCLK. ...
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... The AD7811 and AD7812 are tested using the CCIF standard where two input frequencies near the top end of the input bandwidth are used. In this case, the second and third order terms are of different significance ...
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... The Control Register is a 10-bit-wide, write only register. The Control Register is written to when the AD7811 receives a falling edge on its TFS pin. The AD7811 will maintain the same configuration until a new control byte is written to the part. The control register can be written to at the same time data is being read. This latter feature enhances throughput rates when software control is being used or when the analog input channels are being changed frequently. The power-up default register contents are all zeros ...
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... This is the package address bit used in conjunction with the package address pin to allow two AD7812s to share the same serial bus. The AD7812 can also share the same serial bus with the AD7811. When a control word is written to the control register of the AD7812 the control word is ignored if the package address bit in the con- trol byte does not match how the package address pin is hardwired ...
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... Table I. AD7811 Channel Configurations CH0 Description 0 V Single-Ended with Respect to AGND IN1 1 V Single-Ended with Respect to AGND IN2 0 V Single-Ended with Respect to AGND IN3 1 V Single-Ended with Respect to AGND IN4 0 V Pseudo Differential with Respect to V ...
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... OSC Analog Input Figure 5 shows an equivalent circuit of the analog input struc- ture of the AD7811 and AD7812. The two diodes D1 and D2 provide ESD protection for the analog inputs. Care must be taken to ensure that the analog input signal never exceeds the supply rails by more than 200 mV. This will cause these diodes to become forward biased and start conducting current into the substrate ...
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... An example of the pseudo differential scheme using the AD7811 is shown in Figure 6. The relevant bits in the AD7811 Control Register are set as follows DIF/SGL = 1, CH1 = CH2 = 0, i.e., V pseudo differential with respect to V IN1 applied to V but in the pseudo differential scheme the sam- IN1 pling capacitor is connected to V ...
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... When V AD7812 are in a low current mode of operation. In order to carry out a conversion the AD7811 and AD7812 must first be powered up by writing to the control register of each ADC to set the power-down bits (i.e., PD1 = 1, PD0 = 1) for a full power-up ...
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... the power-up time is DD 1.5 µs and the conversion time is 2.3 µs, the AD7811 can be said to dissipate 10.5 mW for 3.8 µs (worst-case) during each conversion cycle. If the throughput rate is 10 kSPS, the cycle time is 100 µs and the average power dissipated during each cycle is (3.8/100) × ...
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... The CONVST signal should be logic high at the end of the conversion to prevent the part from powering down. The serial port on the AD7811 and AD7812 is enabled on the rising edge of the first SCLK after the rising edge of the RFS signal—see Serial Interface section. As explained earlier, this rising edge ...
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... DB9 DB8 (Point “B”), whichever occurs latest before initiating a serial read. The serial port of the AD7811 and AD7812 is still func- tional even though the devices have been powered down. Because it is possible serial read from the part while it is ...
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... The serial interface on the AD7811 and AD7812 allows the parts to be directly connected to a range of many different microprocessors. This section explains how to interface the AD7811 and AD7812 with some of the more common micro- controller and DSP serial interface protocols. AD7811/AD7812 to PIC16C6x/7x The PIC16C6x Synchronous Serial Port (SSP) is configured as an SPI Master with the Clock Polarity bit = 0 ...
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... AD7811/AD7812 ADDITIONAL PINS OMITTED FOR CLARITY AD7811/AD7812 to DSP56xxx The connection diagram in Figure 25 shows how the AD7811 and AD7812 can be connected to the SSI (Synchronous Serial Interface) of the DSP56xxx family of DSPs from Motorola. The TMS320C5x SSI is operated in Synchronous Mode (SYN bit in CRB =1) ...
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... AD7811/AD7812 0.210 (5.33) 0.160 (4.06) 0.115 (2.93) 0.006 (0.15) 0.002 (0.05) SEATING PLANE OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 16-Lead Plastic DIP (N-16) 0.840 (21.33) 0.745 (18.93 0.280 (7.11) 0.240 (6.10 PIN 1 0.060 (1.52) 0.015 (0.38) MAX 0.130 (3.30) MIN 0.100 0.070 (1.77) SEATING 0.022 (0.558) PLANE (2.54) 0.045 (1.15) 0.014 (0.356) BSC 16-Lead Small Outline Package (SOIC) (R-16A) 0 ...
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... PIN 1 0.002 (0.05) 0.0433 (1.10) MAX 0.0118 (0.30) 0.0256 (0.65) SEATING 0.0079 (0.20) BSC 0.0075 (0.19) PLANE 0.0035 (0.090) AD7811/AD7812 0.325 (8.25) 0.195 (4.95) 0.300 (7.62) 0.115 (2.93) 0.130 (3.30) MIN 0.015 (0.381) 0.008 (0.204) 0.0291 (0.74) x 45° 0.0098 (0.25) 0.0500 (1.27) 8° 0° 0.0157 (0.40) 0.028 (0.70) 8° 0° 0.020 (0.50) ...