Burr Brown Corporation DAC908U-1K, DAC908U, DAC908E-2K5, DAC908E Datasheet

®

For most current data sheet and other product

information, visit www.burr-brown.com

DAC908

DAC908

DAC908

8-Bit, 165MSPS

DIGITAL-TO-ANALOG CONVERTER

FEATURES

● SINGLE +5V OR +3V OPERATION

●

HIGH SFDR:

● LOW GLITCH: 3pV-s

● LOW POWER: 170mW at +5V

● INTERNAL REFERENCE:

Optional Ext. Reference
Adjustable Full-Scale Range
Multiplying Option

DESCRIPTION

The DAC908 is a high-speed, digital-to-analog converter (DAC)
offering an 8-bit resolution option within the SpeedPlus family
of high-performance converters. Featuring pin compatibility
among family members, the DAC900, DAC902, and DAC904
provide a component selection option to an 10-, 12-, and 14-bit
resolution, respectively. All models within this family of D/A
converters support update rates in excess of 165MSPS with
excellent dynamic performance, and are especially suited to
fulfill the demands of a variety of applications.

The advanced segmentation architecture of the DAC908 is
optimized to provide a high Spurious-Free Dynamic Range
(SFDR) for single-tone, as well as for multi-tone signals—
essential when used for the transmit signal path of communica­tion systems.

The DAC908 has a high impedance (200kΩ) current output with
a nominal range of 20mA and an output compliance of up to

1.25V. The differential outputs allow for both a differential, or
single-ended analog signal interface. The close matching of the
current outputs ensures superior dynamic performance in the
differential configuration, which can be implemented with a
transformer.

Utilizing a small geometry CMOS process, the monolithic
DAC908 can be operated on a wide, single-supply range of
+2.7V to +5.5V. Its low power consumption allows for use in
portable and battery operated systems. Further optimization can
be realized by lowering the output current with the adjustable
full-scale option.

5.04MHz

Output at

100MSPS: 67dBc

TM

APPLICATIONS

● MEDICAL INSTRUMENTATION

Ultrasound (DBF)

● VIDEO, DIGITAL TV

● WAVEFORM GENERATION

Direct Digital Synthesis (DDS)
Arbitrary Waveform Generation (ARB)

● TEST INSTRUMENTATION

● COMMUNICATIONS

For noncontinuous operation of the DAC908, a power-down
mode results in only 45mW of standby power.

The DAC908 comes with an integrated 1.24V bandgap refer­ence and edge-triggered input latches, offering a complete
converter solution. Both +3V and +5V CMOS logic families
can be interfaced to the DAC908.

The reference structure of the DAC908 allows for additional
flexibility by utilizing the on-chip reference, or applying an
external reference. The full-scale output current can be adjusted
over a span of 2mA to 20mA, with one external resistor, while
maintaining the specified dynamic performance.

The DAC908 is available in the SO-28 and TSSOP-28 pack­ages.

FSA

REF

INT/EXT

+V

DAC908

IN

+1.24V Ref.

AGND CLK DGND

BW

A

Current

Sources

+V

D

Switches

Segmented

Switches

Latches

8-Bit Data Input

D7...D0

LSB

I

OUT

I

OUT

BYP

PD

International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: [phone]

Twx: 910-952-1111 • Internet: http://www.burr-brown.com/ • Cable: BBRCORP • Telex: 066-6491 • FAX: [phone] • Immediate Product Info: [phone]

©

1999 Burr-Brown Corporation PDS-1507B Printed in U.S.A. April, 2000

1

DAC908

®

SPECIFICATIONS

At TA = full specified temperature range, +VA = +5V, +VD = +5V, differential transformer coupled output, 50Ω doubly terminated, unless otherwise specified.

DAC908U/E

PARAMETER CONDITIONS MIN TYP MAX UNITS

Resolution 8 Bits
Output Update Rate (f
Output Update Rate 2.7V to 3.3V 125 165 MSPS
Full Specified Temperature Range, Operating Ambient, T

STATIC ACCURACY

Differential Nonlinearity (DNL) f
Integral Nonlinearity (INL) –0.5 ±0.25 +0.5 LSB

DYNAMIC PERFORMANCE TA = +25°C
Spurious Free Dynamic Range (SFDR) To Nyquist

= 1.0MHz, f

f

OUT

= 2.1MHz, f

f

OUT

= 5.04MHz, f

f

OUT

= 5.04MHz, f

f

OUT

= 20.2MHz, f

f

OUT

= 25.3MHz, f

f

OUT

= 41.5MHz, f

f

OUT

= 27.4MHz, f

f

OUT

= 54.8MHz, f

f

OUT

Spurious Free Dynamic Range within a Window

= 2.1MHz, f

f

OUT

= 5.04MHz, f

f

OUT

Total Harmonic Distortion (THD)

= 2.1MHz, f

f

OUT

= 5.04MHz, f

f

OUT

= 20.2MHz, f

f

OUT

Output Settling Time
Output Rise Time
Output Fall Time

(2)

(2)

Glitch Impulse 3 pV-s

DC-ACCURACY

Full-Scale Output Range
Output Compliance Range –1.0 +1.25 V
Gain Error With Internal Reference –10 ±1 +10 %FSR
Gain Error With External Reference –10 ±2 +10 %FSR
Gain Drift With Internal Reference ±120 ppmFSR/°C
Offset Error With Internal Reference –0.025 +0.025 %FSR
Offset Drift With Internal Reference ±0.1 ppmFSR/°C
Power Supply Rejection, +V
Power Supply Rejection, +V
Output Noise I
Output Resistance 200 kΩ
Output Capacitance I

REFERENCE

Reference Voltage +1.24 V
Reference Tolerance ±5%
Reference Voltage Drift ±50 ppmFSR/°C
Reference Output Current 10 µA
Reference Input Resistance 1MΩ
Reference Input Compliance Range 0.1 1.25 V
Reference Small Signal Bandwidth

DIGITAL INPUTS

Logic Coding Straight Binary
Latch Command Rising Edge of Clock
Logic High Voltage, V
Logic Low Voltage, V
Logic High Voltage, V
Logic Low Voltage, V
Logic High Current
Logic Low Current, I
Input Capacitance 5pF

) 4.5V to 5.5V 165 200 MSPS

CLOCK

(1)

CLOCK

= 25MSPS 64 70 dBc

CLOCK

= 50MSPS 69 dBc

CLOCK

= 50MSPS 67 dBc

CLOCK

= 100MSPS 67 dBc

CLOCK

= 100MSPS 61 dBc

CLOCK

= 125MSPS 57 dBc

CLOCK

= 125MSPS 51 dBc

CLOCK

= 165MSPS 58 dBc

CLOCK

= 165MSPS 52 dBc

CLOCK

= 50MSPS 2MHz Span 70 dBc

CLOCK

= 100MSPS 4MHz Span 69 dBc

CLOCK

= 50MSPS –72 dBc

CLOCK

= 100MSPS –66 dBc

CLOCK

= 100MSPS –60 dBc

CLOCK

(2)

TA = +25°C

= 25MSPS, f

A

= 1.0MHz –0.5 ±0.25 +0.5 LSB

OUT

to 0.1% 30 ns

–40 +85 °C

10% to 90% 2 ns
10% to 90% 2 ns

(3)

(FSR) All Bits High, I

A
D

(4)

IH

IL

IH

IL

,

(5)

I

IH

IL

OUT

OUT

= 20mA, R

, I

OUT

OUT

= 50Ω 50 pA/√Hz

LOAD

to Ground 12 pF

+VD = +5V 3.5 5 V
+VD = +5V 0 1.2 V
+VD = +3V 2 3 V
+VD = +3V 0 0.8 V
+VD = +5V ±20 µA
+VD = +5V ±20 µA

2.0 20.0 mA

–0.2 +0.2 %FSR/V

–0.025 +0.025 %FSR/V

1.3 MHz

The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.

®

DAC908

2

SPECIFICATIONS (Cont.)

At TA = +25°C, +VA = +5V, +VD = +5V, differential transformer coupled output, 50Ω doubly terminated, unless otherwise specified.

DAC908U/E
PARAMETER CONDITIONS MIN TYP MAX UNITS
POWER SUPPLY

Supply Voltages

+V

A

+V

D

Supply Current

I

VA

, Power-Down Mode 1.1 2 mA

I

VA

I

VD

Power Dissipation +5V, I

Power Dissipation, Power-Down Mode 45 mW
Thermal Resistance,

SO-28 75 °C/W
TSSOP-28 50 °C/W

NOTES: (1) At output I
Section for details. (4) Reference bandwidth depends on size of external capacitor at the BW pin and signal level. (5) Typically 45µA for the PD pin, which has an
internal pull-down resistor. (6) Measured at f

(6)

= 20mA 170 230 mW

OUT

= 2mA 50 mW

+3V, I

OUT

θ

JA

, while driving a virtual ground. (2) Measured single-ended into 50Ω Load. (3) Nominal full-scale output current is 32x I

OUT

= 50MSPS and f

CLOCK

= 1.0MHz.

OUT

+2.7 +5 +5.5 V
+2.7 +5 +5.5 V

24 30 mA

815mA

; see Application

REF

ABSOLUTE MAXIMUM RATINGS

+VA to AGND ........................................................................ –0.3V to +6V

+VD

to DGND........................................................................ –0.3V to +6V

AGND to DGND ................................................................. –0.3V to +0.3V

+VA to +VD .............................................................................. –6V to +6V

CLK, PD to DGND ...................................................... –0.3V to VD + 0.3V

D0-D7 to DGND .......................................................... –0.3V to VD + 0.3V

, I

to AGND............................................................–1V to VA + 0.3V

I

OUT

OUT

BW, BYP to AGND.......................................................–0.3V to VA + 0.3V

REFIN, FSA to AGND.................................................. –0.3V to VA + 0.3V

INT/EXT to AGND........................................................ –0.3V to VA + 0.3V

Junction Temperature .................................................................... +150°C

Case Temperature ......................................................................... +100°C

Storage Temperature..................................................................... +125°C

This integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.

ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.

ELECTROSTATIC
DISCHARGE SENSITIVITY

PACKAGE/ORDERING INFORMATION

PACKAGE SPECIFIED

PRODUCT PACKAGE NUMBER RANGE MARKING NUMBER

DRAWING TEMPERATURE PACKAGE ORDERING TRANSPORT

DAC908U SO-28 217 –40°C to +85°C DAC908U DAC908U Rails

"""""DAC908U/1K Tape and Reel

DAC908E TSSOP-28 360 –40°C to +85°C DAC908E DAC908E Rails

"""""DAC908E/2K5 Tape and Reel

NOTE: (1) Models with a slash (/) are available only in Tape and Reel in the quantities indicated (e.g., /2K5 indicates 2500 devices per reel). Ordering 2500 pieces
of “DAC908E/2K5” will get a single 2500-piece Tape and Reel.

(1)

MEDIA

DEMO BOARD ORDERING INFORMATION

PRODUCT ORDERING NUMBER COMMENT

DAC908U DEM-DAC90xU Populated evaluation board without D/A converter. Order sample of desired DAC90x model separately.
DAC908E DEM-DAC908E Populated evaluation board including the DAC908E.

DEMO BOARD

3

DAC908

®

Top View SO/TSSOP

(MSB) Bit 1

Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7

(LSB) Bit 8

NC
NC
NC
NC
NC
NC

1
2
3
4
5
6
7

DAC908

8

(1)

9

(1)

10

(1)

11

(1)

12

(1)

13

(1)

14

28
27
26
25
24
23
22
21
20
19
18
17
16
15

CLK
+V

D

DGND

(1)

NC
+V

A

BYP
I

OUT

I

OUT

AGND
BW
FSA
REF

IN

INT/EXT
PD

NOTE: (1) NC pins should be left unconnected or grounded.

PIN DESCRIPTIONSPIN CONFIGURATION

PIN DESIGNATOR DESCRIPTION

1 Bit 1 Data Bit 1 (D7), MSB
2 Bit 2 Data Bit 2 (D6)
3 Bit 3 Data Bit 3 (D5)
4 Bit 4 Data Bit 4 (D4)
5 Bit 5 Data Bit 5 (D3)
6 Bit 6 Data Bit 6 (D2)
7 Bit 7 Data Bit 7 (D1)
8 Bit 8 Data Bit 8 (D0), LSB

9 NC No Connection
10 NC No Connection
11 NC No Connection
12 NC No Connection
13 NC No Connection
14 NC No Connection
15 PD Power Down, Control Input; Active

16 INT/EXT Reference Select Pin; Internal (= 0) or

17 REF

IN

18 FSA Full-Scale Output Adjust
19 BW Bandwidth/Noise Reduction Pin:

20 AGND Analog Ground
21 I
22 I
23 BYP Bypass Node: Use 0.1µF to AGND
24 +V
25 NC No Connection

OUT
OUT

A

26 DGND Digital Ground
27 +V
28 CLK Clock Input

D

High.

Contains internal pull-down circuit;

may be left unconnected if not used.

External (= 1) Reference Operation.
Reference Input/Ouput. See Applications

section for further details.

Bypass with 0.1µF to +V
Performance.

for Optimum

A

Complementary DAC Current Output
DAC Current Output

Analog Supply Voltage, 2.7V to 5.5V

Digital Supply Voltage, 2.7V to 5.5V

TYPICAL CONNECTION CIRCUIT

+5V +5V

0.1µF

+V

A

DAC908

FSA

REF

IN

R

SET

0.1µF

INT/EXT

+1.24V Ref.

AGND CLK DGND

BW

Current

Sources

+V

D

Switches

Segmented

Switches

Latches

8-Bit Data Input

D7.......D0

LSB

MSB

I

OUT

I

OUT

BYP

PD

0.1µF

50Ω

20pF

50Ω

1:1

20pF

®

DAC908

4

TIMING DIAGRAM

CLK

D7- D0

I

OUT

t

1

t

t

S

H

t

PD

t

2

t

SET

SYMBOL DESCRIPTION MIN TYP MAX UNITS

t

1

t

2

t

S

t

H

t

PD

t

SET

Clock Pulse High Time 6.25 ns

Clock Pulse Low Time 6.25 ns

Data Setup Time 2 ns

Data Hold Time 2 ns

Propagation Delay Time (t1+t2)+1 ns

Output Settling Time to 0.1% 25 ns

®

5

DAC908