Diodes Incorporated ZXCT1041E5TA

Overview

ZXCT1041E5TA from Zetex Semiconductors is a bidirectional precision high-side current monitor IC with fixed 10× gain, 2.7V–20V common-mode input range, ±0.8V differential sense range, and open-collector Flag pin indicating current direction. It achieves ±2% total output error at +100mV sense voltage and operates down to 35µA quiescent current in portable battery management systems.

For engineers reviewing the ZXCT1041E5TA datasheet, ZXCT1041E5TA pinout, ZXCT1041E5TA application, or ZXCT1041E5TA equivalent, key selection criteria include bidirectional sensing capability, SOT23-5 package constraints, 300 kHz bandwidth, 60 dB CMRR at 100 mV_RMS, and compatibility with low-voltage battery stacks (up to 4 Li-ion cells).

Technical Context

The ZXCT1041 employs dual anti-parallel transconductance amplifiers with matched 1.5 kΩ internal resistors and a shared 15 kΩ gain-setting resistor, delivering precise 10× scaling independent of external components. Its open-collector Flag output enables level-shifting across wide voltage domains - e.g., monitoring a 12 V rail while interfacing to a 3.3 V microcontroller.

Offset trimming on amplifier 1 ensures ±2% accuracy at +100 mV sense input; accuracy degrades to ±5% at −100 mV due to asymmetry in reverse-current path characterization. The device maintains stable operation from −40°C to +125°C with 30 ppm/°C V_OUT temperature coefficient.

Key Specifications

Pinout & Package

SOT23-5 surface-mount package (JEDEC MO-178AA), 2.7 mm × 2.2 mm footprint, 1.3 mm max height, thermal resistance θ_JA ≈ 250°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bidirectional high-side current monitoring applications.

Compared with INA219BIDR and TSC2101IYDT, the ZXCT1041E5TA uniquely combines analog output, open-collector flag, bidirectional sensing, and 35 µA IQ in SOT23-5 - making it optimal for compact, low-power, analog-centric battery and motor control designs requiring real-time polarity detection.

Availability

ZXCT1041E5TA is available at Aetrix Electronics and suitable for battery management systems, overcurrent protection circuits, and motor control feedback loops requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for ZXCT1041E5TA 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 plc (now part of Diodes Incorporated) was a UK-based designer of high-performance analog and discrete semiconductors, ISO 9001 and TS16949 certified, with focus on precision signal conditioning and power management.

The ZXCT series targets precision current sensing in space-constrained, low-power applications - specifically engineered for high-side, bidirectional measurement in battery-powered and automotive subsystems.

FAQ

What is the minimum sense voltage required for reliable Flag assertion?

The Flag trip point is specified at ±2.5 mV referred to V_SENSE, meaning reliable direction detection occurs with ≥3 mV differential input under typical conditions. At 10 mV V_SENSE, Flag transitions cleanly with <1 µs delay, enabling use with 10 mΩ shunts at 1 A load. Accuracy degrades below 5 mV due to offset drift.

Can ZXCT1041E5TA operate with a 2.5 V supply rail?

No - the absolute minimum common-mode voltage is 2.7 V per datasheet specifications. Operation below 2.7 V risks undefined Flag behavior and reduced gain accuracy. For 2.5 V systems, consider the ZXCT1009 (2.0 V min) or redesign with a local 3.3 V LDO to power the S+ pin.

How does the S+ pin supply current vary with sense voltage?

S+ pin current ranges from 10 µA (V_SENSE = 0 V) to 24 µA (V_SENSE = ±150 mV), varying linearly with |V_SENSE|. This current flows through the high-side rail and must be included in total system supply calculations - e.g., 24 µA added to 10 A load contributes negligible error (<0.00025%).

Is external filtering required on the OUT pin for ADC interfacing?

A 10 nF capacitor to GND at the OUT pin is recommended to reduce high-frequency noise from PCB coupling, especially near switching regulators. The 300 kHz bandwidth allows ≤100 kHz anti-aliasing without compromising transient response; no series resistor is needed due to low output impedance (<100 Ω).