ADS1174IPAPR datasheet(9/35 Pages) TI

9 / 35 page

www.ti.com

OVERVIEW

Modulator1

Digital

Filter1

VREFP

IN1

VREFN

REF

TEST[1:0]

FORMAT[2:0]

CLK

SYNC

PWDN

(1)

[4:1]/[8:1]

CLKDIV

MODE

DRDY/FSYNC

SCLK

DOUT[4:1]/[8:1]

(1)

DIN

SPI

and

Frame-Sync

Interface

Control

Logic

AINP1

AINN1

VCOM

Modulator2

Digital

Filter2

IN2

AINP2

AINN2

Modulator4/8

(1)

Digital

Filter4/8

(1)

IN4/8

AINP4/8

(1)

AINN4/8

(1)

DVDD

AVDD

AGND

DGND

IOVDD

NOTE:(1)TheADS1174hasfourchannels;theADS1178haseightchannels.

ADS1174

ADS1178

SBAS373 – OCTOBER 2007

To allow tradeoffs between speed and power, two

The ADS1174 (quad) and ADS1178 (octal) are 16-bit,

modes of operation are supported: High-Speed and

delta-sigma ADCs. They offer the combination of

Low-Power. Table 1 summarizes the performance of

excellent

linearity,

low

noise,

and

low

power

each mode.

consumption. Figure 1 shows the block diagram. Note

that both devices are the same, except the ADS1174

In High-Speed mode, the data rate is 52kSPS, and in

has four ADCs, and the ADS1178 has eight ADCs.

Low-Power mode, the power dissipation is only

The

pinout

and

package

the

ADS1178

8mW/channel at 10.5kSPS.

compatible with the ADS1174, permitting drop-in

The ADS1174/78 is configured by simply setting the

expandability. The converters are comprised of either

appropriate I/O pins—there are no registers to

four

(ADS1174)

eight

(ADS1178)

advanced,

program. Data is retrieved over a serial interface that

6th-order, chopper-stabilized, delta-sigma modulators

supports both SPI and Frame-Sync formats. The

followed by low-ripple, linear phase FIR filters. The

ADS1174/78 has a daisy-chainable output and the

modulators measure the differential input signal, VIN =

ability to synchronize externally, so it can be used

(AINP – AINN), against the differential reference,

conveniently in systems requiring more than eight

VREF = (VREFP – VREFN). The digital filters receive

channels.

the modulator signal and provide a low-noise digital

output.

Figure 1. ADS1174/ADS1178 Block Diagram

Table 1. Operating Mode Performance Summary

POWER DISSIPATION

DATA RATE

PASSBAND

SNR

NOISE

PER CHANNEL(1)

MODE

(SPS)

(Hz)

(dB)

(LSBPP)

(mW)

High-Speed

52,734

23,889

Low-Power

10,547

4,536

(1)

Measured with all channels operating.

Submit Documentation Feedback

Product Folder Link(s): ADS1174 ADS1178

ADS1174IPAPR датащи(PDF) 9 Page - Texas Instruments

ADS1174IPAPR датащи(HTML) 9 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

датащи скачать

ссылки URL