Diodes Incorporated ZXCT199A1DW-7

Overview

ZXCT199A1DW-7 from Diodes Incorporated is a zero-drift, bidirectional current shunt monitor IC designed for high-precision sensing across low-value shunts in high-current systems. It delivers 50V/V fixed gain, ±150μV max input offset voltage (–40°C to +125°C), rail-to-rail output swing, and operates from 2.7V to 26V supply with 100μA max quiescent current. Used in server power rails and industrial motor controllers where 10mV full-scale shunt drop and –0.1V to 26V common-mode range are critical.

For engineers reviewing the ZXCT199A1DW-7 datasheet, ZXCT199A1DW-7 pinout, ZXCT199A1DW-7 application, or ZXCT199A1DW-7 equivalent, key selection criteria include its bidirectional sensing capability via REF pin biasing, zero-drift architecture enabling <0.5μV/°C drift, 90dB min CMRR over temperature, and SOT363 package compatibility with high-density PCB layouts.

Technical Context

The ZXCT199A1DW-7 implements a precision difference amplifier topology with zero-drift chopper-stabilized core, enabling stable DC-coupled current measurement under wide common-mode transients. Its internal resistor network sets fixed 50V/V gain, and the REF pin accepts externally applied bias (0V to V+) to configure unidirectional or bidirectional output response.

Input stage tolerates –0.1V to 26V common-mode voltage independent of supply, while output swings within 50mV of rails (VOH = V+ – 0.05V, VOL = GND + 5mV) into 10kΩ loads across –40°C to +125°C. PSRR exceeds ±0.1μV/V and CMRR reaches 120dB typical at 25°C, supporting accurate sensing in noisy power-conversion environments.

Key Specifications

Pinout & Package

Package: 6-pin SOT363 (2.1mm × 2.0mm × 1.0mm, 0.95mm pitch), surface-mount, RoHS-compliant, halogen-free.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current-sense amplifier applications.

Compared with INA240A1D and MAX4080TASA+, the ZXCT199A1DW-7 uniquely combines 26V common-mode tolerance, 50V/V gain optimized for 10mV shunts, and configurable bidirectionality via REF-making it optimal for high-current, wide-rail industrial and computing power systems requiring minimal external components.

Availability

ZXCT199A1DW-7 is available at Aetrix Electronics and suitable for server farm power management, industrial motor drives, telecom rectifier modules, and programmable DC load calibration requiring stable component supply and long-term production continuity.

Supply support for ZXCT199A1DW-7 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and connectivity applications.

The ZXCT199 series belongs to Diodes' precision analog portfolio, engineered specifically for high-accuracy, low-shunt-drop current monitoring in industrial, computing, and telecom power systems where zero-drift performance and wide common-mode operation are essential.

FAQ

What is the maximum common-mode voltage the ZXCT199A1DW-7 can measure?

The ZXCT199A1DW-7 supports a common-mode input range of –0.1V to 26V, independent of supply voltage. This allows direct high-side sensing on 24V bus rails even when powered from a lower 3.3V or 5V supply, eliminating level-shifters or isolation barriers in many applications.

How does the REF pin enable bidirectional current sensing?

The REF pin sets the output's zero-current baseline: grounding REF yields unidirectional output (0V to V+), while applying mid-supply voltage (e.g., 2.5V on 5V rail) creates symmetric ±output swing for bidirectional flow. This avoids external op-amps or dual-supply designs needed by conventional amplifiers.

Can the ZXCT199A1DW-7 operate with a 3.3V supply while monitoring a 24V shunt?

Yes. The device's input stage tolerates up to 26V common-mode voltage regardless of V+ voltage. With 3.3V supply, the output swings from ~5mV to ~3.25V, fully compatible with 3.3V ADCs-enabling compact, low-power sensing on high-voltage rails without auxiliary supplies.

What is the impact of input filtering resistors on measurement accuracy?

Adding unmatched source resistors >10Ω at IN+/IN− degrades CMRR and introduces gain error. For ZXCT199A1DW-7 with 50V/V gain, 10Ω resistors add ~0.84% gain error; matched resistors and buffered REF minimize this. Input RC filters must satisfy 2×RS×CF ≥ LSHUNT/RSHUNT to avoid bandwidth loss from shunt inductance.