AMC1304M25 - Reinforced Isolated Modulator With LDO Regulator, ±250mV Input, and CMOS Interface

The AMC1304 is a precision, delta-sigma (ΔΣ) modulator with the output separated from the input circuitry by a capacitive double isolation barrier that is highly resistant to magnetic interference. This barrier is certified to provide reinforced isolation of up to 7000 V_PEAK according to the DIN V VDE V 0884-10, UL1577 and CSA standards. Used in conjunction with isolated power supplies, the device prevents noise currents on a high common-mode voltage line from entering the local system ground and interfering with or damaging low voltage circuitry.

The input of the AMC1304 is optimized for direct connection to shunt resistors or other low voltage-level signal sources. The unique low input voltage range of the ±50-mV device allows significant reduction of the power dissipation through the shunt while supporting excellent ac and dc performance. By using an appropriate digital filter (that is, as integrated on the TMS320F2807x or TMS320F2837x families) to decimate the bit stream, the device can achieve 16 bits of resolution with a dynamic range of 81 dB (13.2 ENOB) at a data rate of 78 kSPS.

On the high-side, the modulator is supplied by an integrated low-dropout (LDO) regulator that allows an unregulated input voltage between 4 V and 18 V (LDOIN). The isolated digital interface operates from a 3.3-V or 5-V power supply (DVDD).

The AMC1304 is available in a wide-body SOIC-16 (DW) package and is specified from –40°C to 125°C.

• Pin-Compatible Family Optimized for Shunt-Resistor-Based Current Measurements:
  • ±50-mV or ±250-mV Input Voltage Ranges
  • CMOS or LVDS Digital Interface Options
• Excellent DC Performance Supporting High-Precision Sensing on System Level:
  • Offset Error: ±50 µV or ±100 µV (max)
  • Offset Drift: 1.3 µV/°C (max)
  • Gain Error: ±0.2% or ±0.3% (max)
  • Gain Drift: ±40 ppm/°C (max)
• Safety-Related Certifications:
  • 7000-V_PK Reinforced Isolation per DIN V VDE V 0884-10 (VDE V 0884-10): 2006-12
  • 5000-V_RMS Isolation for 1 Miinute per UL1577
  • CAN/CSA No. 5A-Component Acceptance Service Notice, IEC 60950-1: 2005, and IEC60065: 2014 End Equipment Standards
• Transient Immunity: 15 kV/µs (min)
• High Electromagnetic Field Immunity
  (see Application Note SLLA181A)
• External 5-MHz to 20-MHz Clock Input for
  Easier System-Level Synchronization
• On-Chip 18-V LDO Regulator
• Fully Specified Over the Extended Industrial Temperature Range