Analog Devices AD7569AR, AD7569AQ, AD7569AN, AD7569TQ, AD7569TE Datasheet

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Analog Devices AD7569AR, AD7569AQ, AD7569AN, AD7569TQ, AD7569TE Datasheet

LC2MOS

a Complete, 8-Bit Analog I/0 Systems

AD7569/AD7669

FEATURES

2 ms ADC with Track/Hold

1 ms DAC with Output Amplifier

AD7569, Single DAC Output AD7669, Dual DAC Output

On-Chip Bandgap Reference Fast Bus Interface

Single or Dual 5 V Supplies

GENERAL DESCRIPTION

The AD7569/AD7669 is a complete, 8-bit, analog I/O system on a single monolithic chip. The AD7569 contains a high speed successive approximation ADC with 2 μs conversion time, a track/ hold with 200 kHz bandwidth, a DAC and an output buffer amplifier with 1 μs settling time. A temperature-compensated 1.25 V bandgap reference provides a precision reference voltage for the ADC and the DAC. The AD7669 is similar, but contains two DACs with output buffer amplifiers.

A choice of analog input/output ranges is available. Using a supply voltage of +5 V, input and output ranges of zero to 1.25 V and zero to 2.5 volts may be programmed using the RANGE input pin. Using a ±5 V supply, bipolar ranges of ±1.25 V or

±2.5 V may be programmed.

Digital interfacing is via an 8-bit I/O port and standard microprocessor control lines. Bus interface timing is extremely fast, allowing easy connection to all popular 8-bit microprocessors. A separate start convert line controls the track/hold and ADC to give precise control of the sampling period.

AD7569 FUNCTIONAL BLOCK DIAGRAM

AD7669 FUNCTIONAL BLOCK DIAGRAM

PRODUCT HIGHLIGHTS

The AD7569/AD7669 is fabricated in Linear-Compatible CMOS (LC2MOS), an advanced, mixed technology process combining precision bipolar circuits with low power CMOS logic. The AD7569 is packaged in a 24-pin, 0.3" wide “skinny” DIP, a 24-terminal SOIC and 28-terminal PLCC and LCCC packages. The AD7669 is available in a 28-pin, 0.6" plastic DIP, 28-terminal SOIC and 28-terminal PLCC package.

REV. B

Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

1.Complete Analog I/O on a Single Chip.

The AD7569/AD7669 provides everything necessary to interface a microprocessor to the analog world. No external components or user trims are required and the overall accuracy of the system is tightly specified, eliminating the need to calculate error budgets from individual component specifications.

2.Dynamic Specifications for DSP Users.

In addition to the traditional ADC and DAC specifications, the AD7569/AD7669 is specified for ac parameters, including signal-to-noise ratio, distortion and input bandwidth.

3.Fast Microprocessor Interface.

The AD7569/AD7669 has bus interface timing compatible with all modern microprocessors, with bus access and relinquish times less than 75 ns and write pulse width less than 80 ns.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 617/329-4700

World Wide Web Site: http://www.analog.com

Fax: 617/326-8703

© Analog Devices, Inc., 1996

AD7569/AD7669–SPECIFICATIONS

 

 

 

 

 

 

1

(VDD = +5 V 6 5%; VSS2 = RANGE = AGNDDAC = AGNDADC = DGND = 0 V; RL = 2 kV, CL = 100 pF to AGNDDAC

DAC SPECIFICATIONS

unless otherwise noted. All specifications TMIN to TMAX unless otherwise noted.)

 

 

 

 

 

 

 

 

 

AD7569

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

J, A Versions3

AD7569

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AD7669

K, B

AD7569

AD7569

 

 

 

 

Parameter

 

 

 

J Version

Versions

S Version

T Version

Units

Conditions/Comments

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

STATIC PERFORMANCE

 

 

 

 

 

 

 

 

Resolution4

 

 

 

8

8

8

8

Bits

 

 

 

 

Total Unadjusted Error5

±2

±2

±3

±3

LSB typ

 

 

 

 

Relative Accuracy5

±1

±1/2

±1

±1/2

LSB max

 

 

 

 

Differential Nonlinearity5

±1

±3/4

±1

±3/4

LSB max

Guaranteed Monotonic

 

Unipolar Offset Error

±2

±1.5

±2

±1.5

 

DAC data is all 0s; VSS = 0 V

 

@ +25°C

 

 

 

LSB max

Typical tempco is 10 μV/°C for +1.25 V range

 

TMIN to TMAX

±2.5

±2

±2.5

±2

LSB max

DAC data is all 0s; VSS = –5 V

 

Bipolar Zero Offset Error

±2

±1 5

±2

±1.5

 

 

@ +25°C

 

 

 

LSB max

Typical tempco is 20 μV/°C for ±1.25 V range

 

TMIN to TMAX

±2.5

±2

±2.5

±2

LSB max

 

 

 

 

Full-Scale Error6 (AD7569 Only)

±2

±1

±2

±1

 

VDD = 5 V

 

 

 

@ +25°C

 

 

 

LSB max

 

 

 

 

TMIN to TMAX

±3

±2

±4

±3

LSB max

 

 

 

 

Full-Scale Error6 (AD7669 Only)

±3

 

 

 

 

VDD = 5 V

 

 

 

@ +25°C

 

 

 

 

 

 

LSB max

 

 

 

 

TMIN to TMAX

±4.5

 

 

 

LSB max

 

 

 

 

DACA/DACB Full-Scale Error Match6

±2.5

 

 

 

 

 

 

 

 

(AD7669 Only)

 

 

 

LSB max

VDD = 5 V

VDD = ±5%

 

Full Scale/

VDD, TA = +25°C

0.5

0.5

0.5

0.5

LSB max

VOUT = 2.5 V;

 

Full Scale/

VSS, TA = +25°C

0.5

0.5

0.5

0.5

LSB max

VOUT = –2.5 V;

VSS = ±5%

 

Load Regulation at Full Scale

0.2

0.2

0.2

0.2

LSB max

RL = 2 kΩ to °/C

DYNAMIC PERFORMANCE

 

 

 

 

 

 

 

 

 

Signal-to-Noise Ratio5 (SNR)

44

46

44

46

dB min

VOUT = 20 kHz full-scale sine wave with fSAMPLING = 400 kHz

Total Harmonic Distortion5 (THD)

48

48

48

48

dB max

VOUT = 20 kHz full-scale sine wave with fSAMPLING = 400 kHz

 

Intermodulation Distortion5 (IMD)

55

55

55

55

dB typ

fa = 18.4 kHz, fb = 14.5 kHz with fSAMPLING = 400 kHz

ANALOG OUTPUT

 

 

 

 

 

 

 

 

Output Voltage Ranges

 

 

 

 

 

 

 

 

 

Unipolar

 

 

 

0 to +1.25/2.5

 

 

 

Volts

VDD = +5 V, VSS = 0 V

 

Bipolar

 

 

 

±1.25/±2.5

 

 

 

Volts

VDD = +5 V, VSS = –5 V

LOGIC INPUTS

 

 

 

 

 

 

 

 

 

CS

,

X

/B,

WR

, RANGE,

RESET

, DB0–DB7

 

 

 

 

 

 

 

 

 

Input Low Voltage, VINL

0.8

0.8

0.8

0.8

V max

 

 

 

 

Input High Voltage, VINH

2.4

2.4

2.4

2.4

V min

 

 

 

 

Input Leakage Current

10

10

10

10

μA max

VIN = 0 to VDD

 

 

 

Input Capacitance7

10

10

10

10

pF max

 

 

 

 

DB0–DB7

 

 

 

 

 

 

 

 

 

 

 

 

Input Coding (Single Supply)

 

 

Binary

 

 

 

 

 

 

Input Coding (Dual Supply)

 

 

2s Complement

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AC CHARACTERlSTICS7

 

 

 

 

 

Settling time to within ±1/2 LSB of final value

 

Voltage Output Settling Time

 

 

 

 

 

 

Positive Full-Scale Change

2

2

2

2

μs max

Typically 1 μs

 

 

 

Negative Full-Scale Change (Single Supply)

4

4

4

4

μs max

Typically 2 μs

 

 

 

Negative Full-Scale Change (Dual Supply)

2

2

2

2

μs max

Typically 1 μs

 

 

Digital-to-Analog Glitch Impulse5

15

15

15

15

nV secs typ

 

 

 

 

Digital Feedthrough5

1

1

1

1

nV secs typ

VIN = ±2.5 V, 50 kHz Sine Wave

 

VIN to VOUT Isolation

60

60

60

60

dB typ

DAC to DAC Crosstalk5 (AD7669 Only)

1

 

 

 

nV secs typ

 

 

 

 

DACA to DACB Isolation5 (AD7669 Only)

–70

 

 

 

dB max

 

 

 

POWER REQUIREMENTS

 

 

 

 

 

 

 

 

VDD Range

 

 

 

4.75/5.25

4.75/5.25

4.75/5.25

4.75/5.25

V min/V max

For Specified Performance

VSS Range (Dual Supplies)

–4.75/–5.25

–4.75/–5.25

–4.75/–5.25

–4.75/–5.25

V min/V max

Specified Performance also applies to VSS = 0 V

 

 

 

 

 

 

 

 

 

 

 

 

 

 

for unipolar ranges.

IDD

 

 

 

 

 

 

 

 

VOUT = VIN = 2.5 V; Logic Inputs = 2.4 V; CLK = 0.8 V

 

(AD7569)

 

 

 

13

13

13

13

mA max

Output unloaded

 

(AD7669)

 

 

 

18

 

 

 

mA max

Outputs unloaded

 

ISS (Dual Supplies)

 

 

 

 

 

VOUT = VIN = –2.5 V; Logic Inputs = 2.4 V; CLK = 0.8 V

 

(AD7569)

 

 

 

4

4

4

4

mA max

Output unloaded

 

(AD7669)

 

 

 

6

 

 

 

mA max

Outputs unloaded

 

 

 

 

 

 

 

 

 

DAC/ADC MATCHING

 

 

 

 

 

VIN to VOUT match with VIN = ±2.5 V,

Gain Matching6

 

 

 

 

 

 

@ +25°C

 

 

 

1

1

1

1

% typ

20 kHz sine wave

 

TMIN to TMAX

1

1

1

1

% typ

 

 

 

NOTES

1Specifications apply to both DACs in the AD7669. VOUT applies to both VOUTA and VOUTB of the AD7669. 2Except where noted, specifications apply for all output ranges including bipolar ranges with dual supply operation.

3Temperature ranges as follows:

J, K versions; 0°C to +70°C

 

A, B versions; –40°C to +85°C

S, T versions; –55°C to +125°C

41 LSB = 4.88 mV for 0 V to +1.25 V output range, 9.76 mV for 0 V to +2.5 V and ±1.25 V ranges and 19.5 mV for ±2.5 V range. 5See Terminology.

6Includes internal voltage reference error and is calculated after offset error has been adjusted out. Ideal unipolar full-scale voltage is (FS – 1 LSB); ideal bipolar positive full-scale voltage is (FS/2 – 1 LSB) and ideal bipolar negative full-scale voltage is –FS/2.

7Sample tested at +25°C to ensure compliance.

Specifications subject to change without notice.

–2–

REV. B

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AD7569/AD7669

ADC SPECIFICATIONS

(VDD = +5 V 6 5%; VSS1 = RANGE = AGNDDAC = AGNDDAC = DGND = 0 V; fCLK = 5 MHz external unless other-

wise noted. All specifications TMIN to TMAX unless otherwise noted.) Specifications apply to Mode 1 interface.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AD7569

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

J, A Versions3

AD7569

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AD7669

K, B

AD7569

AD7569

 

 

 

Parameter

 

 

 

 

 

 

 

 

J Version

Versions

S Version

T Version

Units

Conditions/Comments

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DC ACCURACY

 

 

 

 

 

 

 

 

 

Resolution3

 

 

 

 

 

 

 

 

8

 

8

8

8

Bits

 

 

 

Total Unadjusted Error4

±3

 

±3

±4

±4

LSB typ

 

 

Relative Accuracy4

±1

 

±1/2

±1

±1/2

LSB max

 

 

Differential Nonlinearity4

±1

 

±3/4

±1

±3/4

LSB max

No Missing Codes

Unipolar Offset Error

±2

 

± 1.5

±2

± 1.5

 

Typical tempco is 10 μV/°C for +1.25 V range; VSS = 0 V

 

@ +25°C

 

 

 

 

 

 

 

 

 

LSB max

 

 

 

TMIN to TMAX

±3

 

± 2.5

±3

± 2.5

LSB max

Typical tempco is 20 μV/°C for + 1.25 V range; VSS = –5 V

Bipolar Zero Offset Error

±3

 

± 2.5

±3

± 2.5

 

 

@ +25°C

 

 

 

 

 

 

 

 

 

LSB max

 

 

 

TMIN to TMAX

± 3.5

 

±3

±4

± 3.5

LSB max

 

 

Full-Scale Error5

 

 

 

 

 

 

VDD = 5 V

 

 

@ +25°C

 

 

 

 

 

 

 

 

–4, +0

–4, +0

–4, +0

–4, +0

LSB max

 

 

 

TMIN to TMAX

–5.5, +1.5

–5.5, +1.5

–7.5, +2

–7.5, +2

LSB max

 

VDD = ±5%

 

Full Scale/

VDD, TA = +25°C

0.5

 

0.5

0.5

0.5

LSB max

VIN = +2.5 V;

 

Full Scale/

VSS, TA = +25°C

0.5

 

0.5

0.5

0.5

LSB max

VIN = –2.5 V;

VSS = ±5%

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DYNAMIC PERFORMANCE

 

 

 

 

 

 

 

 

Signal-to-Noise Ratio4 (SNR)

44

 

46

44

45

dB min

VIN = 100 kHz full-scale sine wave with fSAMPLING = 400 kHz6

 

Total Harmonic Distortion4 (THD)

48

 

48

48

48

dB max

VIN = 100 kHz full-scale sine wave with fSAMPLING = 400 kHz6

 

Intermodulation Distortion4 (IMD)

60

 

60

60

60

dB typ

fa = 99 kHz, fb = 96.7 kHz with fSAMPLING = 400 kHz

 

Frequency Response

0.1

 

0.1

0.1

0.1

dB typ

VIN = ±2.5 V, dc to 200 kHz sine wave

 

Track/Hold Acquisition Time7

200

 

200

300

300

ns typ

 

 

ANALOG INPUT

 

 

 

 

 

 

 

 

 

Input Voltage Ranges

 

 

 

 

 

 

 

 

 

Unipolar

 

 

 

 

 

 

 

 

0 to +1.25/ +2.5

 

 

Volts

VDD = +5 V; VSS = 0 V

 

Bipolar

 

 

 

 

 

 

 

 

±1.25/±2.5

 

 

Volts

VDD = +5 V; VSS = –5 V

 

Input Current

±300

 

±300

±300

±300

μA max

See equivalent circuit Figure 5

 

 

 

Input Capacitance

10

 

10

10

10

pF typ

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LOGIC INPUTS

 

 

 

 

 

 

 

 

 

CS

,

RD

,

ST

, CLK,

RESET

, RANGE

 

 

 

 

 

 

 

 

 

Input Low Voltage, VINL

0.8

 

0.8

0.8

0.8

V max

 

 

 

Input High Voltage, VINH

2.4

 

2.4

2.4

2.4

V min

 

 

 

Input Capacitance8

10

 

10

10

10

pF max

 

 

 

CS

,

RD

,

ST

, RANGE,

RESET

 

 

 

 

 

 

μA max

 

 

 

Input Leakage Current

10

 

10

10

10

V IN = 0 to VDD

 

 

CLK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Input Current

 

 

 

 

 

 

 

 

 

 

IINL

 

 

 

 

 

 

 

 

–1.6

 

–1.6

–1.6

–1.6

mA max

VIN = 0 V

 

 

 

IINH

 

 

 

 

 

 

 

 

40

 

40

40

40

μA max

VIN = VDD

 

LOGIC OUTPUTS

 

 

 

 

 

 

 

 

 

DB0–DB7,

INT

,

BUSY

 

 

 

 

 

 

 

 

 

 

VOL, Output Low Voltage

0.4

 

0.4

0.4

0.4

V max

ISINK = 1.6 mA

 

 

VOH, Output High Voltage

4.0

 

4.0

4.0

4.0

V min

ISOURCE = 200 μA

 

DB0–DB7

 

 

 

 

 

 

 

 

 

 

 

 

 

μA max

 

 

 

Floating State Leakage Current

10

 

10

10

10

 

 

 

Floating State Output Capacitance8

10

 

10

10

10

pF max

 

 

 

Output Coding (Single Supply)

 

 

Binary

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Output Coding (Dual Supply)

 

 

2s Complement

 

 

 

 

 

 

 

 

 

 

 

 

 

CONVERSION TIME

 

 

 

 

 

μs max

 

 

 

With External Clock

2

 

2

2

2

fCLK = 5 MHz

 

 

With Internal Clock, TA = +25°C

1.6

 

1.6

1.6

1.6

μs min

Using recommended clock components shown in Figure 21.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2.6

 

2.6

2.6

2.6

μs max

Clock frequency can be adjusted by varying RCLK.

 

 

 

 

 

 

 

 

 

POWER REQUIREMENTS

As per DAC Specifications

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NOTES

1Except where noted, specifications apply for all ranges including bipolar ranges with dual supply operation. 2Temperature ranges are as follows: J, K versions; 0°C to +70°C

A, B versions; –40°C to +85°C S, T versions; –55°C to +125°C

31 LSB = 4.88 mV for 0 V to +1.25 V range, 9.76 mV for 0 V to +2.5 V and ±1.25 V ranges and 19.5 mV for +2.5 V range. 4See Terminology.

5Includes internal voltage reference error and is calculated after offset error has been adjusted out. Ideal unipolar last code transition occurs at (FS – 3/2 LSB). Ideal bipolar last code transition occurs at (FS/2 – 3/2 LSB).

6Exact frequencies are 101 kHz and 384 kHz to avoid harmonics coinciding with sampling frequency.

7Rising edge of BUSY to falling edge of ST. The time given refers to the acquisition time, which gives a 3 dB degradation in SNR from the tested figure. 8Sample tested at +25°C to ensure compliance.

Specifications subject to change without notice.

REV. B

–3–

AD7569/AD7669–TIMING CHARACTERISTICS1 (See Figures 8, 10, 12; VDD = 5 V 6 5%; VSS = 0 V or –5 V 6 5%)

 

 

Limit at

Limit at

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Limit at

TMIN, TMAX

TMIN, TMAX

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Parameter

258C (All Grades)

(J, K, A, B Grades)

(S, T Grades)

Units

 

Test Conditions/Comments

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DAC Timing

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

t1

80

80

90

ns min

 

WR

Pulse Width

t2

0

0

0

ns min

 

CS, A/B to WR Setup Time

t3

0

0

0

ns min

 

CS, A/B to WR Hold Time

t4

60

70

80

ns min

 

Data Valid to WR Setup Time

t5

10

10

10

ns min

 

Data Valid to WR Hold Time

ADC Timing

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

t6

50

50

50

ns min

 

ST

 

Pulse Width

t7

110

130

150

ns max

 

ST to BUSY Delay

t8

20

30

30

ns max

 

BUSY to INT Delay

t9

0

0

0

ns min

 

BUSY to CS Delay

t10

0

0

0

ns min

 

CS to

RD

Setup Time

t11

60

75

90

ns min

 

RD Pulse Width Determined by t13.

t12

0

0

0

ns min

 

CS to RD Hold Time

t132

60

75

90

ns max

 

Data Access Time after

RD

; CL = 20 pF

t143

95

120

135

ns max

Data Access Time after RD; CL = 100 pF

10

10

10

ns min

 

Bus Relinquish Time after

RD

 

 

60

75

85

ns max

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

t15

65

75

85

ns max

 

RD

to

INT

Delay

t16

120

140

160

ns max

 

RD to BUSY Delay

t172

60

75

90

ns max

 

Data Valid Time after

BUSY

; CL = 20 pF

 

90

115

135

ns max

Data Valid Time after

BUSY

; CL = 100 pF

NOTES

1Sample tested at +25°C to ensure compliance. All input control signals are specified with tR = tF = 5 ns (10% to 90% of +5 V) and timed from a voltage level of 1.6 V. 2t13 and t17 are measured with the load circuits of Figure 1 and defined as the time required for an output to cross either 0.8 V or 2.4 V.

3tl4 is defined as the time required for the data line to change 0.5 V when loaded with the circuit of Figure 2. Specifications subject to change without notice.

a. High-Z to VOH

b. High-Z to VOL

Figure 1. Load Circuits for Data Access Time Test

ABSOLUTE MAXIMUM RATINGS

VDD to AGNDDAC or AGNDADC . . . . . . . . . . . . . –0.3 V, +7 V VDD to DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V, +7 V VDD to VSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V, +14 V AGNDDAC or AGNDADC to DGND . . . . –0.3 V, VDD + 0.3 V AGNDDAC to AGNDADC . . . . . . . . . . . . . . . . . . . . . . . . . ±5 V Logic Voltage to DGND . . . . . . . . . . . . . –0.3 V, VDD + 0.3 V CLK Input Voltage to DGND . . . . . . . . . –0.3 V, VDD + 0.3 V

VOUT (VOUTA, VOUTB) to

AGND1DAC . . . . . . . . . . . . . . . . . VSS – 0.3 V, VDD + 0.3 V VIN to AGNDADC . . . . . . . . . . . . . . . VSS – 0.3 V, VDD + 0.3 V

NOTE

1Output may be shorted to any voltage in the range VSS to VDD provided that the power dissipation of the package is not exceeded. Typical short circuit current for a short to AGND or VSS is 50 mA.

a. VOH to High-Z

b. VOL to High-Z

Figure 2. Load Circuits for Bus Relinquish Time Test

Power Dissipation (Any Package) to +75°C . . . . . . . . 450 mW Derates above 75°C by . . . . . . . . . . . . . . . . . . . . . 6 mW/°C

Operating Temperature Range

Commercial (J, K) . . . . . . . . . . . . . . . . . . . . . . 0°C to +70°C Industrial (A, B) . . . . . . . . . . . . . . . . . . . . . –40°C to +85°C Extended (S, T) . . . . . . . . . . . . . . . . . . . . –55°C to +125°C Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C Lead Temperature (Soldering, 10 secs) . . . . . . . . . . . +300°C

*Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other condition above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

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 the AD7569/AD7669 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.

WARNING!

ESD SENSITIVE DEVICE

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REV. B

AD7569/AD7669

NOTE:

The term DAC (Digital-to-Analog Converter) throughout the data sheet applies equally to the dual DACs in the AD7669 as well as to the single DAC of the AD7569 unless otherwise stated. It follows that the term VOUT applies to both VOUTA and VOUTB of the AD7669 also.

TERMINOLOGY Total Unadjusted Error

Total unadjusted error is a comprehensive specification that includes internal voltage reference error, relative accuracy, gain and offset errors.

Relative Accuracy (DAC)

Relative Accuracy or endpoint nonlinearity is a measure of the maximum deviation from a straight line passing through the endpoints of the DAC transfer function. It is measured after allowing for offset and gain errors. For the bipolar output ranges, the endpoints of the DAC transfer function are defined as those voltages that correspond to negative full-scale and positive fullscale codes. For the unipolar output ranges, the endpoints are code 1 and code 255. Code 1 is chosen because the amplifier is now working in single supply and, in cases where the true offset of the amplifier is negative, it cannot be seen at code 0. If the relative accuracy were calculated between code 0 and code 255, the “negative offset” would appear as a linearity error. If the offset is negative and less than 1 LSB, it will appear at code 1, and hence the true linearity of the converter is seen between code 1 and code 255.

Relative Accuracy (ADC)

Relative Accuracy is the deviation of the ADC’s actual code transition points from a straight line drawn between the endpoints of the ADC transfer function. For the bipolar input ranges, these points are the measured, negative, full-scale transition point and the measured, positive, full-scale transition point. For the unipolar ranges, the straight line is drawn between the measured first LSB transition point and the measured full-scale transition point.

Differential Nonlinearity

Differential Nonlinearity is the difference between the measured change and an ideal 1 LSB change between any two adjacent codes. A specified differential nonlinearity of ±1 LSB max ensures monotonicity (DAC) or no missed codes (ADC). A differential nonlinearity of ±3/4 LSB max ensures that the minimum step size (DAC) or code width (ADC) is 1/4 LSB, and the maximum step size or code width is 3/4 LSB.

Digital-to-Analog Glitch Impulse

Digital-to-Analog Glitch Impulse is the impulse injected into the analog output when the digital inputs change state with the DAC selected. It is normally specified as the area of the glitch in nV secs and is measured when the digital input code is changed by 1 LSB at the major carry transition.

Digital Feedthrough

Digital Feedthrough is also a measure of the impulse injected to the analog output from the digital inputs, but is measured when the DAC is not selected. It is essentially feedthrough across the die and package. It is also a measure of the glitch impulse transferred to the analog output when data is read from the internal ADC. It is specified in nV secs and is measured with WR high and a digital code change from all 0s to all 1s.

DAC-to-DAC Crosstalk (AD7669 Only)

The glitch energy transferred to the output of one DAC due to an update at the output of the second DAC. The figure given is the worst case and is expressed in nV secs. It is measured with an update voltage of full scale.

DAC-to-DAC Isolation (AD7669 Only)

DAC-to-DAC Isolation is the proportion of a digitized sine wave from the output of one DAC, which appears at the output of the second DAC (loaded with all 1s). The figure given is the worst case for the second DAC output and is expressed as a ra-

tio in dBs. It is measured with a digitized sine wave (fSAMPLING = 100 kHz) of 20 kHz at 2.5 V pk-pk.

Signal-to-Noise Ratio

Signal-to-Noise Ratio (SNR) is the measured signal to noise at the output of the converter. The signal is the rms magnitude of the fundamental. Noise is the rms sum of all the nonfundamental signals (excluding dc) up to half the sampling frequency.

SNR is dependent on the number of quantization levels used in the digitization process; the more levels, the smaller the quantization noise. The theoretical SNR for a sine wave is given by

SNR = (6.02N + 1.76) dB

where N is the number of bits. Thus for an ideal 8-bit converter, SNR = 50 dB.

Harmonic Distortion

Harmonic Distortion is the ratio of the rms sum of harmonics to the fundamental. For the AD7569/AD7669, Total Harmonic Distortion (THD) is defined as

20 log V22 +V32 +V42 +V52 +V62

V1

where V1 is the rms amplitude of the fundamental and V2, V3, V4, V5 and V6 are the rms amplitudes of the individual harmonics.

Intermodulation Distortion

With inputs consisting of sine waves at two frequencies, fa and fb, any active device with nonlinearities will create distortion products, of order (m + n), at sum and difference frequencies of mfa ± nfb where m, n = 0, l, 2, 3,… . Intermodulation terms are those for which m or n is not equal to zero. For example, the second order terms include (fa + fb) and (fa – fb) and the third order terms include (2fa + fb), (2fa – fb), (fa + 2fb) and (fa – 2fb).

REV. B

–5–

AD7569/AD7669

 

AD7569 PIN CONFIGURATIONS

 

DIP, SOIC

PLCC

LCCC

AD7669 PIN CONFIGURATIONS

DIP, SOIC

PLCC

ORDERING GUIDE

 

 

Relative

 

 

Temperature

Accuracy

Package

Model

Range

TMIN –TMAX

Option1

AD7569JN

0°C to +70°C

±1 LSB

N-24

AD7569JR

0°C to +70°C

±1 LSB

R-24

AD7569AQ

–40°C to +85°C

±1 LSB

Q-24

AD7569SQ2

–55°C to +125°C

±1 LSB

Q-24

AD7569BN

–40°C to +85°C

±0.5 LSB

N-24

AD7569KN

0°C to +70°C

±0.5 LSB

N-24

AD7569BR

–40°C to +85°C

±0.5 LSB

R-24

AD7569BQ

–40°C to +85°C

±0.5 LSB

Q-24

AD7569TQ2

–55°C to +125°C

±1/2 LSB

Q-24

AD7569JP

0°C to +70°C

±1 LSB

P-28A

AD7569SE2

–55°C to +125°C

±1 LSB

E-28A

AD7569KP

0°C to +70°C

±1/2 LSB

P-28A

AD7569TE2

–55°C to +125°C

±1/2 LSB

E-28A

AD7669AN

–40°C to +85°C

±1 LSB

N-28

AD7669JN

0°C to +70°C

±1 LSB

N-28

AD7669JP

0°C to +70°C

±1 LSB

P-28A

AD7669AR

–40°C to +85°C

±1 LSB

R-28

AD7669JR

0°C to +70°C

±1 LSB

R-28

NOTES

1E = Leadless Ceramic Chip Carrier; N = Plastic DIP; P = Plastic Leaded Chip Carrier; Q = Cerdip; R = Small Outline SOIC.

2To order MIL-STD-883, Class B processed parts, add /883B to part number. Contact your local sales office for military data sheet.

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REV. B

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