Diodes Incorporated ZXCT1023DFGTA

Overview

ZXCT1023DFGTA from Diodes Incorporated is a precision high-side current sense monitor with fixed 50× gain, operating from 2.5V to 20V common-mode input range and consuming only 3.5µA quiescent current. It uses the sensed rail as its power source, requires only an external sense resistor, and delivers output-referenced-to-GND voltage (V_OUT = 50 × V_SENSE) for battery charge/discharge monitoring in space-constrained Li-ion/polymer systems.

For engineers reviewing the ZXCT1023DFGTA datasheet, ZXCT1023DFGTA pinout, ZXCT1023DFGTA application, or ZXCT1023DFGTA equivalent, key selection criteria include its micropower operation, rail-sourced supply architecture, TDFN1218-4 package footprint, ±3% accuracy at 50mV sense voltage, and suitability for single-cell battery current measurement where ground-plane integrity is critical.

Technical Context

The ZXCT1023DFGTA implements a high-side sensing topology that derives power directly from the S+ pin (the monitored rail), eliminating need for separate supply and reducing system component count. Its internal amplifier features fixed 50 V/V gain with output referenced to GND, enabling direct ADC interfacing without level-shifting.

It operates across a wide common-mode voltage range (2.5V–20V) while maintaining specified accuracy and bandwidth (1 MHz at 50mV V_SENSE). Input bias current at S− is 100nA max, supporting high-value sense resistors without significant error contribution.

Key Specifications

Pinout & Package

Package: TDFN1218-4L (1.2 mm × 1.8 mm, 0.5 mm height, exposed thermal pad connected to GND).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX4080TASA+ and INA219AIDR, the ZXCT1023DFGTA offers the lowest quiescent current (3.5 µA) and smallest footprint (1.2×1.8 mm), making it optimal for space- and energy-constrained high-side analog current sensing where simplicity and longevity are prioritized over digital features or extended voltage range.

Availability

ZXCT1023DFGTA is available at Aetrix Electronics and suitable for battery capacity monitoring, portable charger feedback, and over-current protection circuits requiring stable component supply, long-lifecycle availability, and consistent parametric performance across production batches.

Supply support for ZXCT1023DFGTA 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 manufacturer of discrete semiconductors and analog ICs, specializing in high-efficiency power management, signal integrity, and precision sensing solutions for industrial, computing, and consumer markets.

The ZXCT1023 belongs to Diodes' Zetex high-precision current sensing product line, designed specifically for micropower, rail-sourced, high-side monitoring in battery-powered and space-constrained applications.

FAQ

What is the maximum allowable sense voltage (V_SENSE) for ZXCT1023DFGTA?

The absolute maximum differential sense voltage is +2.5 V, but the recommended operating range is 0–380 mV. At V_SENSE = 380 mV and gain = 50, V_OUT = 19 V - which approaches the upper limit of the output voltage range (VS− − 1 V). Exceeding 380 mV risks output saturation or reduced linearity per datasheet specifications.

Can ZXCT1023DFGTA measure current in a grounded-load configuration?

No - the ZXCT1023DFGTA is strictly a high-side current monitor. Its S+ pin must connect to the high side of the load, and S− to the load's low side (i.e., upstream of the load's ground connection). It cannot be used in low-side (ground-referenced) configurations because its output is GND-referenced and its internal architecture relies on sensing above ground potential.

How does the exposed thermal pad affect PCB layout and thermal performance?

The central paddle is internally connected to GND and must be soldered to a dedicated GND copper pour on the PCB. A minimum 4×4 array of thermal vias (0.3 mm diameter, spaced ≤1 mm apart) is recommended to conduct heat into inner-layer GND planes. This reduces θ_JA by up to 30°C/W and prevents thermal drift in accuracy-critical applications.

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

A 100 pF to 1 nF capacitor between OUT and GND is recommended to reduce high-frequency noise and improve ADC sampling stability. The device's 15 kΩ output resistance forms an RC filter with this capacitor; for 1 MHz bandwidth, ≤100 pF is advised. Larger values degrade step response but improve SNR in DC or slow-sampling applications.