Analog Devices AD7111ABR, AD7111ABN, AD7111UQ-883B, AD7111TE-883B, AD7111LN Datasheet

LC2MOS LOGDAC

17-BIT DAC

17-BIT LATCH

DECODE LOGIC

8-BIT BUFFER

CONTROL LOGIC

AD7111A

I

OUT

AGND

R

FB

V

DD

V

IN

DGND

CS

WR

D0 – D7

a

FEATURES
Dynamic Range: 88.5 dB
Resolution: 0.375 dB
On-Chip Data Latches
+5 V Operation
AD7111A Pin Compatible with AD7524
Low Power

APPLICATIONS
Audio Attenuators
Sonar Systems
Function Generators
Digitally Controlled AGC System

GENERAL DESCRIPTION

The LOGDAC AD7111/AD7111A are monolithic multiplying
D/A converters featuring wide dynamic range in a small pack­age. Both DACs can attenuate an analog input signal over the
range 0 dB to 88.5 dB in 0.375 dB steps. They are available in
16-pin DIPs and SOIC packages. The AD7111 is also available
in a 20-terminal LCCC package.

The degree of attenuation across the DAC is determined by an
8-bit word applied to the onboard decode logic. This 8-bit word
is decoded into a 17-bit word which is then applied to a 17-bit
R-2R ladder. The very fine step resolution, which is available
over the entire dynamic range, is due to the use of this 17-bit
DAC.

The AD7111/AD7111A are easily interfaced to a standard 8-bit
MPU bus via an 8-bit data port and standard microprocessor
control lines. The AD7111
quires a rising edge to load new data to the DAC. The AD7111A
WR is level triggered to allow transparent operation of the
latches, if required. It should also be noted that the AD7111A is
exactly pin and function-compatible with the AD7524, an in­dustry standard 8-bit multiplying DAC. This allows an easy up­grading of existing AD7524 designs which would benefit both
from the wider dynamic range and the finer step resolution of­fered by the AD7111A.

The AD7111/AD7111A are fabricated in Linear Compatible
CMOS (LC2MOS), an advanced, mixed technology process that
combines precision bipolar circuits with low power CMOS logic.

LOGDAC is a registered trademark of Analog Devices, Inc.

WR input is edge triggered and re-

Logarithmic D/A Converter

AD7111/AD7111A

FUNCTIONAL BLOCK DIAGRAMS

V

V

DD

IN

R

FB

AD7111

17-BIT DAC

17-BIT LATCH

DECODE LOGIC

CONTROL LOGIC

WR

CS

8-BIT BUFFER

D0 – D7

DGND

PRODUCT HIGHLIGHTS

1. Wide Dynamic Range: 0 dB to 88.5 dB attenuation range in

0.375 dB steps.

2. Small Package: The AD7111/AD7111A are available in
16-pin DIPs and SOIC packages.

3. Transparent Latch Operation: By tying the
puts low, the DAC latches in the AD7111A can be made
transparent.

4. Fast Microprocessor Interface: Data setup times of 25 ns and
write pulse width of 57 ns make the AD7111A compatible
with modern microprocessors.

I

OUT

AGND

CS and WR in-

REV. 0

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.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] Fax: [phone]

AD7111/AD7111A–SPECIFICA TIONS

(VDD = +5 V, VIN = –10 V dc, I

AD7111–ELECTRICAL CHARACTERISTICS

AD711 except where noted)

= AGND = DGND = O V output amplifier

OUT

Parameter TA = +258CTA = T

NOMINAL RESOLUTION 0.375 0.375 0.375 0.375 dB
ACCURACY RELATIVE TO

0 dB ATTENUATION

0.375 dB Steps:
Accuracy ≤ ±0.17 dB 0 to 36 0 to 36 0 to 30 0 to 30 dB min Guaranteed Attenuation Ranges
Monotonic 0 to 54 0 to 54 0 to 48 0 to 48 dB min for Specified Step Sizes

0.75 dB Steps:
Accuracy ≤ ±0.35 dB 0 to 48 0 to 42 0 to 42 0 to 36 dB min
Monotonic 0 to 72 0 to 66 0 to 72 0 to 60 dB min

1.5 dB Steps:
Accuracy ≤ ±0.7 dB 0 to 54 0 to 48 0 to 42 0 to 42 dB min Full Range Is from 0 dB
Monotonic Full Range 0 to 78 0 to 85.5 0 to 72 dB min to 88.5 dB

3.0 dB Steps:
Accuracy ≤ ±1.4 dB 0 to 66 0 to 54 0 to 60 0 to 48 dB min
Monotonic Full Range Full Range Full Range Full Range dB min

6.0 dB Steps:
Accuracy ≤ ±2.7 dB 0 to 72 0 to 60 0 to 60 0 to 48 dB min
Monotonic Full Range Full Range Full Range Full Range dB min

GAIN ERROR ± 0.1 ± 0.15 ± 0.15 ±0.20 dB max
VIN INPUT RESISTANCE 9/11/15 9/11/15 7/11/18 7/11/18 kΩ min/typ/max
RFB INPUT RESISTANCE 9.3/11.5/15.7 9.3/11.5/15.7 7.3/11.5/18.8 7.3/11.5/18.8 kΩ min/typ/max
DIGITAL INPUTS

VIH (Input High Voltage) 2.4 2.4 2.4 2.4 V min
VIL (Input Low Voltage) 0.8 0.8 0.8 0.8 V max
Input Leakage Current ± 1 ±10 ± 1 ± 10 µA max Digital Inputs = V

SWITCHING CHARACTERISTICS

t

CS

t

CH

t

WR

t

DS

t

DH

t

RFSH

POWER SUPPLY

V

DD

I

DD

NOTE

1

Sample tested at +25°C to ensure compliance.

Specifications subject to change without notice.

AD7111L/C/U Grades AD7111K/B/T Grades

1

0 0 0 0 ns min
0 0 0 0 ns min Chip Select to Write Hold Time
350 500 350 500 ns min Write Pulse Width
175 250 175 250 ns min Data Valid to Write Setup Time

10 10 10 10 ns min Data Valid to Write Hold Time
3 4.5 3 4.5 µs min Refresh Time

+5 +5 +5 +5 V
1 4 1 4 mA max Digital Inputs = VIL or V
500 1000 500 1000 µA max Digital Inputs = 0 V or VDD;

MIN

, T

MAXTA

= +258CTA = T

MIN

, T

Units Conditions/Comments

MAX

Chip Select to Write Setup Time

See Figure 6

DD

IH

AC PERFORMANCE CHARACTERISTICS

to test. VDD = +5 V, VIN = –10 V dc except where noted, I

Parameter TA = +258CTA = T

DC Supply Rejection, ∆Gain/∆V
Propagation Delay 3.0 4.5 3.0 4.5 µs max Full-Scale Change Measured from

Digital-to-Analog Glitch Impulse 100 100 nV secs typ Measured with AD843 as Output

Output Capacitance, Pin 1 185 185 185 185 pF max
Input Capacitance, Pin 15 and Pin 16 7 7 7 7 pF max
Feedthrough at 1 kHz –94 –72 –94 –68 dB max
Total Harmonic Distortion –91 –91 –91 –91 dB typ VIN = 6 V rms at 1 kHz
Output Noise Voltage Density 70 70 70 70 nV/√Hz max Includes AD711 Amplifier Noise
Digital Input Capacitance 7 7 7 7 pF max

Specifications subject to change without notice.

DD

AD7111L/C/U Grades AD7111K/B/T Grades

0.001 0.005 0.001 0.005 dB per % max

These characteristics are included for design guidance only and are not subject

= AGND = DGND = O V, output amplifier AD711 except where noted.

OUT

MIN

, T

MAXTA

= +258CTA = T

MIN

, T

Units Conditions/Comments

MAX

∆VDD = ±10%, Input Code = 00000000

WR Going High, CS = 0 V
Amplifier for Code Transition

10000000 to 00000000
C1 of Figure 1 is 0 pF

–2–

REV. 0

AD7111/AD7111A

AD7111A–ELECTRICAL CHARACTERISTICS

(VDD = +5 V, VIN = –10 V dc, I
AD711 except where noted)

= AGND = DGND = O V output amplifier

OUT

AD7111AC Grade AD7111AB Grade

Parameter TA = +258CTA = T

MIN

, T

MAXTA

= +258CTA = T

MIN

, T

Units Conditions/Comments

MAX

NOMINAL RESOLUTION 0.375 0.375 0.375 0.375 dB
ACCURACY RELATIVE TO

0 dB ATTENUATION

0.375 dB Steps:
Accuracy ≤ ±0.17 dB 0 to 36 0 to 36 0 to 30 0 to 30 dB min Guaranteed Attenuation Ranges
Monotonic 0 to 54 0 to 54 0 to 48 0 to 48 dB min for Specified Step Sizes

0.75 dB Steps:
Accuracy ≤ ±0.35 dB 0 to 48 0 to 42 0 to 42 0 to 36 dB min
Monotonic 0 to 72 0 to 66 0 to 72 0 to 60 dB min

1.5 dB Steps:
Accuracy ≤ ±0.7 dB 0 to 54 0 to 48 0 to 48 0 to 42 dB min Full Range Is from 0 dB
Monotonic Full Range 0 to 78 0 to 85.5 0 to 72 dB min to 88.5 dB

3.0 dB Steps:
Accuracy ≤ ±1.4 dB 0 to 66 0 to 54 0 to 60 0 to 48 dB min
Monotonic Full Range Full Range Full Range Full Range dB min

6.0 dB Steps:
Accuracy ≤ ±2.7 dB 0 to 72 0 to 60 0 to 60 0 to 48 dB min
Monotonic Full Range Full Range Full Range Full Range dB min

GAIN ERROR ±0.1 ±0.15 ±0.15 ±0.20 dB max
VIN INPUT RESISTANCE 9/11/15 9/11/15 7/11/18 7/11/18 kΩ min/typ/max
RFB INPUT RESISTANCE 9.3/11.5/15.7 9.3/11.5/15.7 7.3/11.5/18.8 7.3/11.5/18.8 kΩ min/typ/max
DIGITAL INPUTS

VIH (Input High Voltage) 2.4 2.4 2.4 2.4 V min
VIL (Input High Voltage) 0.8 0.8 0.8 0.8 V max
Input Leakage Current ±1 ±10 ±1 ±10 µA max Digital Inputs = V

SWITCHING CHARACTERISTICS

t

CS

t

CH

t

WR

t

DS

t

DH

1

0 0 0 0 ns min

Chip Select to Write Setup Time
0 0 0 0 ns min Chip Select to Write Hold Time
57 57 57 57 ns min Write Pulse Width
25 25 25 25 ns min Data Valid to Write Setup Time
10 10 10 10 ns min Data Valid to Write Hold Time

POWER SUPPLY

V

DD

I

DD

+5 +5 +5 +5 V Digital Inputs = VIL or V
1 2 1 2 mA max CS = WR = 0 V
1 1 1 1 mA max Digital Inputs = 0 V or VDD;

See Figure 6

NOTE

1

Sample tested at +25°C to ensure compliance.

Specifications subject to change without notice.

DD

IH

AC PERFORMANCE CHARACTERISTICS

to test. VDD = +5 V, VIN = –10 V dc except where noted, I

These characteristics are included for design guidance only and are not subject

= AGND = DGND = O V, output amplifier AD711 except where noted.

OUT

AD7111AC Grade AD7111AB Grade

Parameter TA = +258CTA = T

DC Supply Rejection, ∆Gain/∆V
Propagation Delay 1 1.5 1 1.5 µs max Full-Scale Change Measured from

DD

0.001 0.005 0.001 0.005 dB per % max

MIN

, T

MAXTA

= +258CTA = T

MIN

, T

Units Conditions/Comments

MAX

∆VDD = ±10%, Input Code = 00000000

WR Going High, CS = 0 V

Digital-to-Analog Glitch Impulse 10 20 10 20 nV secs typ Measured with AD843 as Output

Amplifier for Code Transition
10000000 to 00000000

C1 of Figure 1 is 0 pF
Output Capacitance, Pin 1 50 50 50 50 pF max
Input Capacitance, Pin 15 and Pin 16 7 7 7 7 pF max
Feedthrough at 1 kHz –94 –90 –92 –90 dB max
Total Harmonic Distortion –91 –91 –91 –91 dB typ VIN = 6 V rms at 1 kHz
Output Noise Voltage Density 70 70 70 70 nV/√Hz max Includes AD711 Amplifier Noise
Digital Input Capacitance 7 7 7 7 pF max

Specifications subject to change without notice.

REV. 0

–3–