Diodes Incorporated DDTA143FUA-7

Overview

DDTA143FUA-7 from Diodes Incorporated is a PNP pre-biased small-signal transistor in SOT-323 package, featuring built-in bias resistors R1 = 4.7 kΩ and R2 = 22 kΩ (R1 ≠ R2), V_CEO = −50 V, I_C(max) = −100 mA, and DC current gain (h_FE) of 68 at −10 mA/−5 V. It serves as a logic-level interface switch in low-power digital control circuits.

For engineers reviewing the DDTA143FUA-7 datasheet, DDTA143FUA-7 pinout, DDTA143FUA-7 application, or DDTA143FUA-7 equivalent, key selection criteria include input voltage thresholds (V_IN(on) = −2.5 V @ −20 mA), output saturation voltage (V_CE(sat) ≤ −0.3 V), resistor tolerance (±30% on R1), resistance ratio tolerance (±20% on R2/R1), and thermal resistance (625 °C/W).

Technical Context

This device integrates a PNP bipolar junction transistor with two discrete external-base biasing resistors-R1 connected between base and input, R2 between base and emitter-enabling single-resistor logic-level drive without external bias network. Its R1 ≠ R2 topology provides asymmetric turn-on/turn-off behavior optimized for digital switching.

Designed for surface-mount operation at ambient temperatures from −55 °C to +150 °C, it delivers stable DC current gain (h_FE = 68 min) and low saturation voltage under −5 mA to −100 mA load conditions, with f_T = 250 MHz confirming suitability for moderate-speed switching up to ~10 MHz.

Key Specifications

Pinout & Package

Package: SOT-323 - ultra-small surface-mount plastic package (2.0–2.2 mm × 1.15–1.35 mm × 0.25–0.40 mm height), RoHS-compliant, moisture sensitivity level 1, weight ≈ 0.006 g.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP pre-biased transistor applications.

Compared with DDTA143ZUA-7-F, DDTA143FUA-7 offers faster turn-off due to lower R2 (22 kΩ vs. 47 kΩ), reducing storage time; versus DDTC143FUA-7-F, it provides PNP polarity essential for negative-rail load control and direct connection to ground-referenced drivers.

Availability

DDTA143FUA-7 is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and consumer appliance control boards requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for DDTA143FUA-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 manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The DDTA series targets cost-sensitive, space-constrained digital interface applications-delivering pre-biased PNP transistors with standardized SOT-323 footprints and tightly controlled resistor tolerances for reliable logic-level switching.

FAQ

What is the absolute maximum input voltage for DDTA143FUA-7?

The absolute maximum input voltage (V_IN) is specified as −30 V, measured between Pin 1 (Emitter) and Pin 2 (Base). This rating aligns with the device's V_CEO = −50 V and ensures robustness against transient overvoltage events in automotive and industrial environments where load-dump spikes may occur.

Can DDTA143FUA-7 be used in place of a standard PNP transistor with external bias resistors?

Yes-it replaces a discrete PNP transistor plus two base resistors, with identical functional behavior. The internal R1 = 4.7 kΩ and R2 = 22 kΩ match common design values; however, layout must respect the fixed SOT-323 pinout (Emitter = Pin 1, Collector = Pin 3), unlike flexible discrete placement.

What is the typical leakage current when the device is off?

Output leakage current I_O(off) is −0.5 μA maximum at V_CC = −50 V and V_IN = 0 V. This ultra-low off-state current minimizes power loss in always-on systems such as battery-backed IoT nodes and ensures reliable high-impedance isolation in multiplexed sensor arrays.

Does DDTA143FUA-7 support reflow soldering per J-STD-020?

Yes-it is qualified for lead-free reflow soldering per J-STD-020C, with moisture sensitivity level 1 (unlimited floor life at ≤30 °C/60% RH). The matte tin finish on Alloy 42 leads ensures reliable wetting, and the UL 94V-0 mold compound withstands peak reflow temperatures up to 260 °C.