Diodes Incorporated ZXCT1050E5TA

Overview

ZXCT1050E5TA from Zetex Semiconductors is a precision wide-input-range current monitor IC designed for high-side or low-side load current sensing in power management systems. It operates with 2.7–20V supply, supports 0 to V_CC−2V common-mode input range, delivers ±3% total output error at 30mV sense voltage, and features 50µA quiescent current in SOT23-5 package - enabling accurate monitoring in battery-powered motor control and overcurrent protection circuits.

For engineers reviewing the ZXCT1050E5TA datasheet, ZXCT1050E5TA pinout, ZXCT1050E5TA application, or ZXCT1050E5TA equivalent, key selection criteria include its dual-rail gain configuration (R_SH/R_G), 300 kHz bandwidth, 70 dB CMRR, 60 dB PSRR, and ability to sense down to 0V common-mode - critical for short-circuit detection and ground-referenced solenoid control.

Technical Context

The ZXCT1050 functions as a transconductance-based current monitor with externally set gain via two resistors: R_SH sets internal transconductance (typ. 100 µS), while R_G converts output current to voltage (gain = 10 × R_G/R_SH). Its rail-to-rail input stage enables operation at 0V common-mode, distinguishing it from line-powered alternatives like ZXCT1021.

It employs a current-output architecture where sensed differential voltage (V_SENSE) forces proportional current through R_G, yielding scalable output voltage (e.g., 1V out per 100mV sense at gain=10). Input bias currents are ultra-low (≤150 nA), minimizing error from shunt resistor parasitics and supporting high-accuracy measurement at low currents.

Key Specifications

Pinout & Package

The ZXCT1050E5TA is housed in a RoHS-compliant SOT23-5 surface-mount package (3.0 × 2.8 mm footprint, 1.0 mm height), optimized for space-constrained PCB layouts in portable and embedded power systems.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current monitoring applications.

Compared with MAX4080TASA+ and INA219AIDR, the ZXCT1050E5TA uniquely supports true 0 V common-mode sensing and offers fully configurable analog gain via discrete resistors - making it optimal for cost-sensitive, ground-referenced, or mixed-signal designs requiring minimal BOM count and deterministic analog response.

Availability

ZXCT1050E5TA is available at Aetrix Electronics and suitable for power supply overcurrent protection, DC motor control, and battery management systems requiring stable component supply, long-term lifecycle support, and consistent parametric performance across temperature extremes.

Supply support for ZXCT1050E5TA 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

Zetex Semiconductors (now part of Diodes Incorporated) is a UK-based designer of high-performance analog and power management ICs, ISO 9001 and TS16949 certified, with focus on precision sensing and efficient power conversion.

The ZXCT series was developed specifically for high-accuracy, low-power current monitoring in space-constrained industrial and portable equipment - emphasizing rail-to-rail input operation, external gain flexibility, and robustness in noisy environments.

FAQ

What is the minimum sense voltage for 1% accuracy?

The ZXCT1050E5TA achieves typical 1% accuracy at 30 mV differential sense voltage due to its ultra-low input offset and matched internal transistors. At lower voltages (e.g., 10 mV), total error increases to ±3%, as specified in the electrical characteristics table under 'Accuracy' test conditions.

Can the device sense current on a 0 V rail?

Yes - the SENSE+ and SENSE− inputs operate from 0 V up to V_CC−2 V, enabling direct connection to ground-referenced shunts. This allows detection of short-circuit currents flowing into ground, unlike line-powered monitors that cease operation below ~2 V common-mode.

How do R_SH and R_G affect bandwidth?

Increasing R_G beyond 40 kΩ or R_SH beyond 10 kΩ reduces bandwidth and introduces load-induced errors. The datasheet specifies 300 kHz bandwidth at R_G = 3.75 kΩ and R_SH = 7.5 kΩ; halving both resistors maintains bandwidth but increases power dissipation in the gain network.

Is the output compatible with standard ADC inputs?

Yes - the OUT pin sinks current into R_G to generate a ground-referenced voltage (0 V to V_CC−2 V), which directly interfaces with most SAR or delta-sigma ADCs. For 3.3 V ADCs, limit V_CC to ≤5.3 V or add a simple resistive divider to avoid exceeding input voltage ratings.