AMC1203 Datasheet, PDF (1/23 Pages) Texas Instruments – 1-Bit, 10MHz, 2nd-Order, Isolated Delta-Sigma Modulator

AMC1203
www.ti.com
SBAS427 – FEBRUARY 2008
1-Bit, 10MHz, 2nd-Order, Isolated Delta-Sigma Modulator
FEATURES
1
•2 16-Bit Resolution
• SNR: 80.5dB min
• THD: –88dB max (AMC1203B)
• ±280mV Input Range with +5V Supply
• Internal 2.5V Reference Voltage: 1% Accuracy
• Gain Error: ±1% (AMC1203B)
• UL1577, IEC60747-5-2 (VDE0884, Rev. 2), and
IEC61010-1 Approved
– Isolation: 4000V_PEAK,
Working Voltage: 560V
– Transient Immunity: 15kV/µs
• Typical 25-Year Life at Rated Working Voltage
(see Application Report SLLA197)
• Operating Temperature Range:
–40°C to +105°C
APPLICATIONS
• Shunt Based Current Sensing in:
– Motor Control
– Uninterruptible Power Supplies
– Power Inverters
– Industrial Process Control
DESCRIPTION
The AMC1203 is a 1-bit, 10MHz, isolated delta-sigma
(ΔΣ) modulator with an output buffer separated from
the input interface circuitry by a silicon dioxide (SiO₂)
isolation barrier. This barrier provides galvanic
isolation of up to 4000V_PEAK. Used in conjunction with
isolated power supplies, these devices prevent noise
currents on a data bus or other circuits from entering
the local ground and interfering with or damaging
sensitive circuitry.
The AMC1203 modulator operates from a +5V supply
with a dynamic range of 95dB. The differential inputs
are ideal for direct connection to shunt resistors or
other low-level signal sources. With the appropriate
digital filter and modulator rate, the device can be
used to achieve 16-bit analog-to-digital (A/D)
conversion with no missing codes. An effective
resolution of 14 bits and an SNR of 85dB (typical)
can be maintained with a sinc³ filter with a decimation
ratio of 256.
The modulator output is translated to a balanced
signal and then transferred by the capacitive isolation
barrier. Across the isolation barrier, a differential
comparator receives the logic transition information,
and then sets or resets a flip-flop and the output
circuit accordingly.
The AMC1203 is available in an SO-8 gull-wing
package. SO-8 and SO-16 packages are planned for
release in 2008. The AMC1203 is characterized for
operation over the ambient temperature range of
–40°C to +105°C.
Isolation Barrier
V_IN+
2nd-Order
DS Modulator
V_IN-
+
-
V_REF
+
-
Output
Buffer
MDAT
POR
BIAS
POR
Buffer
2.5V
V_REF
20MHz
RC
Oscillator
+
-
V_REF
+
-
Output
Buffer
MCLK
1
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2008, Texas Instruments Incorporated