AVDD

DGND

AGND

DVDD

DS

Modulator

DATA

VINP

VINN

2.5V

Ref

CLKIN

AMC1204

AMC1204B

www.ti.com

SBAS512C – APRIL 2011 – REVISED AUGUST 2012

20MHz, Second-Order, Isolated Delta-Sigma Modulator

for Current-Shunt Measurement

Check for Samples: AMC1204, AMC1204B

1

FEATURES

DESCRIPTION

The AMC1204 and AMC1204B are 1-bit digital

2

•

±250mV Input Voltage Range Optimized for

output, isolated delta-sigma (

ΔΣ) modulators that can

Shunt Resistors

be clocked at up to 20MHz. The digital isolation of the

•

Certified Digital Isolation:

modulator output is provided by a silicon dioxide

–

CSA, IEC60747-5-2, and UL1577 Approved

interference. This barrier has been certified to provide

–

basic

galvanic

isolation

of

up

to

–

–

Transient Immunity: 15kV/µs

UL1577,

IEC60747-5-2,

and

CSA

standards

or

specifications.

•

Long Isolation Barrier Lifetime (see

Application Report SLLA197)

The AMC1204 and AMC1204B provide a single-chip

solution for measuring the small signal of a shunt

•

High Electromagnetic Field Immunity

resistor across an isolated barrier. These types of

(see Application Note SLLA181A)

resistors are typically used to sense currents in motor

•

Outstanding AC Performance:

control inverters, green energy generation systems,

–

SNR: 84dB (min)

and other industrial applications. The AMC1204 and

AMC1204B differential inputs easily connect to the

–

THD: –80dB (max)

shunt resistor or other low-level signal sources. An

•

Excellent DC Precision:

internal reference eliminates the need for external

–

INL: ±8LSB (max)

components. When used with an appropriate external

–

Gain Error: ±2% (max)

digital filter, an effective number of bits (ENOB) of 14

is achieved at a data rate of 78kSPS.

•

External Clock Input for Easier

Synchronization

A 5V analog supply (AVDD) is used by the modulator

while the isolated digital interface operates from a 3V,

•

Fully Specified Over the Extended Industrial

3.3V, or 5V supply (DVDD). The AMC1204 and

Temperature Range

AMC1204B are available in SO-16 (DW) packages

and are specified from –40°C to +105°C.

APPLICATIONS

•

Shunt Resistor Based Current Sensing in:

–

Motor Control

–

Green Energy

–

Inverter Applications

–

Uninterruptible Power Supplies

1

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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2

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PRODUCTION DATA information is current as of publication date.

Copyright © 2011–2012, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.