4-Channel, 16-Bit, 1.25 GSPS DAC Slashes power consumption, increases speed

Philip Pratt

Product Marketing Engineer, High Speed Data Converters

High Performance Analog

Applications• Sensors• Motor Control• Test Equipment• Programmable Logic

Controllers• Energy

TI data converter markets and applications

Applications Optical Networking Base Stations Wireless Handsets Cable Modem WiMax

Applications Portable Media

Players Digital Video

Recorders Media Gateways Digital Cameras Smartphones / PDAs

Applications Electrocardiogram

(ECG) CT Scanners Infusion Pumps Pulse Oximetry Ultrasound Systems

Applications Radar Software Defined

Radio Signals Intelligence Satellite

Communications Data Links

MultimediaIndustrial MedicalCommunicationSpace &Defense

Market Drivers • Low Noise• High Accuracy /

Resolution• Low Offset• Low Drift• Power• Packaging

Market Drivers • Speed• Resolution• Bandwidth• Gain• Power• Integration

Market Drivers• Power• Size• Integration• Cost

Market Drivers • Resolution• Sampling Rate• Power• Size• Integration• Cost

Market Drivers • Speed• Resolution• Bandwidth• IF Performance• Power• Integration

Wireless infrastructure market growth continues

• LTE network equipment, including E-

UTRAN (eNodeB) macrocells and

Evolved Packet Core (EPC) equipment,

jumped 704% in 2010 over 2009

• 4G infrastructure market forecast to hit

$16 billion by 2015, driven by LTE and

WiMAX investments

• Mobile broadband service revenue

expected to grow faster than voice and

SMS/MMS, with a 25% 5-year compound

annual growth rate from 2009 to 2014

• Mobile broadband subscribers projected

to reach 1.8 billion worldwide in 2014

(28% of subscribers), driven by

smartphone adoption

Source: Infonetics

Interpolating DACs

Sample Rate (MSPS)

400 800 1000

16

Reso

lution (

Bits)

500-625 1250

DAC5674Single, PLL

4x Interpolation

14

DAC5687Dual, QMC, PLL,

NCO, 8x Interpolation

DAC5686Dual, PLL, NCO

16x Interpolation

DAC3282Dual,

2x Interpolation

DAC3283Dual, QMC

4x Interpolation

DAC5689Dual, QMC,

NCO, 8x Interpolation

DAC5688Dual, QMC, PLL

NCO, 8x Interpolation

DAC5682ZDual, QMC, PLL

NCO, 4x Interpolation

DAC5681ZSingle, QMC, PLL

4x Interpolation

12

DAC3484Quad, 16x Interpolation

312M Input Rate

DAC3482Dual, 16x Interpolation

625M Input Rate

DAC34H84Quad, 16x Interpolation

625M Input Rate

1+GSPS quad DAC comparisonTI DAC slashes power while boosting speed

~ For base stations, wideband repeaters, software defined radios ~

More features and benefits

Feature Benefit

9-mm x 9-mm Multi-row QFN

(DAC3484, DAC3482)

44% smaller than closest competitor

16-bit interleaved 1.25-GSPS input Reduces pin count, layout complexity

and board size

Group delay calibration Improves sideband suppression for

wideband signals

Multi-DAC synchronization Reduces design complexity for

diversity and smart antenna radios

2x-16x interpolation Lowers interface rate, cost of

FPGA/DUC

Two 32-bit NCOs (DAC3484,

DAC34H84)

Independent, fine-tuned, wide-range

output frequency

First TI product with Multi-row QFN

Benefits:

• Great thermal capability

• Higher I/O density

• Customized footprint

88 pins, 9-mm x 9-mm package

DAC3484

DAC3482

DAC3484 diagram

HPA

GC5330

DUC/DDC

CFR/DPD

SDRAM

Main

Diversity

Main

Diversity

IQ DeModulatorTRF3711

Digital Pre-Distortion (DPD)

Feedback Path

IQ Modulator

TRF370315

IQ DeModulatorTRF3711

Two Transmit PathsTwo Receive Paths

Antenna

AntennaAntenna

Antenna

DAC3484

DAC

DAC

DAC

DAC

ADS6422

ADC

ADC

ADC

ADC

CDCE72010CLOCK

IQ Modulator

TRF372017

C6748DSP

ADS41B29

ADC

THS7700

HPA

3G/LTE multimode base station Two transmit, two receive radio with pre-distortion

Unwanted sideband at 200 MHz wideband unadjusted

Ref -20 dBm Att 5 dB

1 AP

CLRWR

A

80 MHz/Center 1.8 GHz Span 800 MHz

3DB

RBW 3 MHz

VBW 10 MHz

SWT 2.5 ms

-120

-110

-100

-90

-80

-70

-60

-50

-40

-30

-20

Date: 30.NOV.2010 11:58:20

DAC3484 settings:

• 307.2 MSPS input rate

• 4x interpoloation

• 200 MHz NCO

• DAC sampling rate:

1228.8 MHz

TRF370315 settings:

• Local oscillator 1.8 GHz

Center 1.8 GHz Spacing, 80 MHz Per Division, Span 800 MHz

Wanted Signal

Unwanted Sideband

Enabling gain and phase correction reduces unwanted sideband; does not eliminate it

Ref -20 dBm Att 5 dB

1 AP

CLRWR

A

80 MHz/Center 1.8 GHz Span 800 MHz

*

3DB

RBW 50 kHz

VBW 200 kHz

SWT 320 ms

-120

-110

-100

-90

-80

-70

-60

-50

-40

-30

-20

Date: 30.NOV.2010 12:09:18

Unwanted Sideband

Reduced

Center 1.8 GHz Spacing, 80 MHz Per Division, Span 800 MHz

Wanted Signal

Ref -20 dBm Att 5 dB

1 AP

CLRWR

A

80 MHz/Center 1.8 GHz Span 800 MHz

*

3DB

RBW 50 kHz

VBW 200 kHz

SWT 320 ms

-120

-110

-100

-90

-80

-70

-60

-50

-40

-30

-20

Date: 30.NOV.2010 12:06:39

Enabling gain, phase AND group delay correction suppresses unwanted sideband

Unwanted Sideband

Suppressed

Wanted Signal

Center 1.8 GHz Spacing, 80 MHz Per Division, Span 800 MHz

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Summary

• Industry’s most power-efficient 4-channel,

16-bit DAC

• At 1.25 GSPS, the DAC3484 is 25% faster

than the next fastest 4-channel DAC

• Consumes only 250 mW per channel in

16x interpolation mode – 65% less than the

closest competitor

• 40% smaller than alternative quad DAC

solutions while supporting data rates up

312.5 MSPS per DAC

• For data rates up to 625 MSPS:

– 2-channel DAC3482

– 4-channel DAC34H84

More information

• DAC3484 overview: www.ti.com/dac3484-pr

• DAC3484 data sheet: www.ti.com/dac3484ds-pr

• New TI signal chain guide: www.ti.com/signalchain-pr

• High Speed Data Converter forum on E2E Community:

www.ti.com/e2ehsdc-pr