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

a		LC2MOS LOGDAC
		Logarithmic D/A Converter
		AD7111/AD7111A

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 WR input is edge triggered and re- 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.

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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.

FUNCTIONAL BLOCK DIAGRAMS

	VDD	VIN
			RFB
AD7111		17-BIT DAC	I OUT
			AGND
		17-BIT LATCH
		DECODE LOGIC
CONTROL LOGIC		8-BIT BUFFER
CS	WR	D0 – D7	DGND

	VDD	VIN
			RFB
AD7111A		17-BIT DAC	I OUT
			AGND
		17-BIT LATCH
		DECODE LOGIC
CONTROL LOGIC		8-BIT BUFFER
CS	WR	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 CS and WR inputs 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.

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

AD7111/AD7111A–SPECIFICATIONS

AD7111–ELECTRICAL CHARACTERISTICS				(VDD = +5 V, VIN = –10 V dc, IOUT = AGND = DGND = O V output amplifier
				AD711 except where noted)
	AD7111L/C/U Grades			AD7111K/B/T Grades
Parameter	TA = +258C	TA = TMIN, TMAX		TA = +258C	TA = TMIN, TMAX	Units	Conditions/Comments
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	kW 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	kW 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	mA max	Digital Inputs = VDD
SWITCHING CHARACTERISTICS1
tCS	0	0		0	0	ns min	Chip Select to Write Setup Time
tCH	0	0		0	0	ns min	Chip Select to Write Hold Time
tWR	350	500		350	500	ns min	Write Pulse Width
tDS	175	250		175	250	ns min	Data Valid to Write Setup Time
tDH	10	10		10	10	ns min	Data Valid to Write Hold Time
tRFSH	3	4.5		3	4.5	ms min	Refresh Time
POWER SUPPLY
VDD	+5	+5		+5	+5	V
IDD	1	4		1	4	mA max	Digital Inputs = VIL or VIH
	500	1000		500	1000	mA max	Digital Inputs = 0 V or VDD;
							See Figure 6

NOTE

1Sample tested at +25°C to ensure compliance. Specifications subject to change without notice.

AC PERFORMANCE CHARACTERISTICS These characteristics are included for design guidance only and are not subject to test. VDD = +5 V, VIN = –10 V dc except where noted, IOUT = AGND = DGND = O V, output amplifier AD711 except where noted.

AD7111L/C/U Grades

AD7111K/B/T Grades

Parameter

TA = +258C TA = TMIN, TMAX

TA = +258C TA = TMIN, TMAX

Units

Conditions/Comments

DC Supply Rejection, DGain/DVDD

0.001

0.005

0.001

0.005

dB per % max

DVDD = ±10%, Input Code = 00000000

Propagation Delay

3.0

4.5

3.0

4.5

ms max

Full-Scale Change Measured from

WR

Going High,

CS

= 0 V

Digital-to-Analog Glitch Impulse

100

100

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

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/Ö

Hz

max

Includes AD711 Amplifier Noise

Digital Input Capacitance

7

7

7

7

pF max

Specifications subject to change without notice.

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AD7111/AD7111A

(VDD = +5 V, VIN = –10 V dc, IOUT = AGND = DGND = O V output amplifier

AD7111A–ELECTRICAL CHARACTERISTICS AD711 except where noted)

	AD7111AC Grade		AD7111AB Grade
Parameter	TA = +258C	TA = TMIN, TMAX	TA = +258C TA = TMIN, TMAX		Units		Conditions/Comments
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	kW 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	kW 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	mA max		Digital Inputs = VDD
SWITCHING CHARACTERISTICS1
tCS	0	0	0	0	ns min		Chip Select to Write Setup Time
tCH	0	0	0	0	ns min		Chip Select to Write Hold Time
tWR	57	57	57	57	ns min	Write Pulse Width
tDS	25	25	25	25	ns min	Data Valid to Write Setup Time
tDH	10	10	10	10	ns min	Data Valid to Write Hold Time
POWER SUPPLY
VDD	+5	+5	+5	+5	V	Digital Inputs = VIL or VIH
IDD	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

1Sample tested at +25°C to ensure compliance. Specifications subject to change without notice.

AC PERFORMANCE CHARACTERISTICS These characteristics are included for design guidance only and are not subject to test. VDD = +5 V, VIN = –10 V dc except where noted, IOUT = AGND = DGND = O V, output amplifier AD711 except where noted.

AD7111AC Grade

AD7111AB Grade

Parameter

TA = +258C TA = TMIN, TMAX

TA = +258C TA = TMIN, TMAX

Units

Conditions/Comments

DC Supply Rejection, DGain/DVDD

0.001

0.005

0.001

0.005

dB per % max

DVDD = ±10%, Input Code = 00000000

Propagation Delay

1

1.5

1

1.5

ms max

Full-Scale Change Measured from

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/Ö

Hz

max

Includes AD711 Amplifier Noise

Digital Input Capacitance

7

7

7

7

pF max

Specifications subject to change without notice.

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