Diodes Incorporated ZXCT1011E5TA

Overview

ZXCT1011E5TA from Zetex Semiconductors is a high-side current sense monitor IC that converts shunt voltage into a proportional output current with 1% typical accuracy, 10 mA/V transconductance (at Rshunt = 120 Ω), and operates from 2.5 V to 20 V supply range. It enables ground-plane–intact load current sensing in battery management and overcurrent protection circuits.

For engineers reviewing the ZXCT1011E5TA datasheet, ZXCT1011E5TA pinout, ZXCT1011E5TA application, or ZXCT1011E5TA equivalent, key selection factors include its 4 µA quiescent current, ±3% accuracy over temperature, SOT23-5 package footprint, and external gain-setting resistor interface for precision scaling.

Technical Context

The ZXCT1011E5TA implements a transconductance-based current-sense architecture where output current Iout = Iq + Vsense × gm, with gm trimmed via external Rshunt (120 Ω nominal). Its high-side topology isolates measurement from ground return paths, eliminating ground-loop errors in motor control and power rail monitoring.

It features a 400 kHz small-signal bandwidth (CL = 5 pF, Rout = 1 kΩ) and 68 dB supply rejection ratio at 200 mV sense input, enabling stable operation in noisy automotive and industrial DC power systems without additional filtering.

Key Specifications

Pinout & Package

Package: SOT23-5 - surface-mount, 5-pin, 2.9 mm × 1.6 mm footprint with 0.95 mm pitch; rated for −40°C to +125°C operation and 300 mW power dissipation at 25°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX4080TASA+ and INA219AIDR, the ZXCT1011E5TA delivers lowest power consumption and smallest footprint for analog current-to-voltage conversion, while requiring external gain-setting and signal conditioning-but offering superior thermal stability and supply rejection in harsh environments.

Availability

ZXCT1011E5TA is available at Aetrix Electronics and suitable for automotive battery monitoring, DC motor overcurrent protection, and portable equipment power management requiring stable component supply and long-term lifecycle support.

Supply support for ZXCT1011E5TA 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 was a UK-based analog IC designer specializing in high-performance, low-power sensor and interface solutions before acquisition by Diodes Incorporated in 2008.

The ZXCT1011 belongs to Zetex's precision current sensing product line, engineered for high-side measurement in space-constrained, thermally demanding applications such as automotive subsystems and industrial power controls.

FAQ

What is the minimum headroom required between Vsense+ and Iout pins?

The ZXCT1011E5TA requires a minimum 2.5 V differential between Vsense+ and the Iout pin to operate correctly. This headroom must accommodate both the voltage drop across Rout (Vout = Iout × Rout) and any output-stage saturation margin. At 100 mV sense input and 10 mA output, a 3 kΩ Rout yields 30 V drop-so supply must exceed 32.5 V unless Rout is reduced accordingly.

Can Pin 1 (N/C) be connected to ground?

Pin 1 is internally unconnected and may be left floating or tied to GND without affecting operation. Zetex documentation confirms no electrical function; grounding it improves EMI immunity in high-noise layouts but introduces no performance benefit or risk.

How does Rshunt value affect accuracy and bandwidth?

Rshunt sets transconductance (gm = 1.2 / Rshunt), so a 1% tolerance in Rshunt causes 1% gain error. Bandwidth remains unchanged-characterized at 400 kHz regardless of Rshunt-as it depends on internal amplifier compensation and Rout–CL loading, not Rshunt.

Is the ZXCT1011E5TA suitable for bidirectional current sensing?

No-the ZXCT1011E5TA is unidirectional and only measures current flowing from Vsense+ to Vsense−. It cannot resolve polarity reversal or negative Vsense values; its input stage saturates below 0 V differential. For bidirectional sensing, consider dual-supply amplifiers like the INA226 or discrete op-amp solutions.