Diodes Incorporated DDTA143XCA-7-F

Overview

DDTA143XCA-7-F 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 = 10 kΩ (R1 ≠ R2), −20 V input voltage range, −100 mA output current capability, and DC current gain (h_FE) of −30 at V_CE = −5 V and I_C = −10 mA. It serves as a logic-level interface switch in low-power digital control circuits.

For engineers reviewing the DDTA143XCA-7-F datasheet, DDTA143XCA-7-F pinout, DDTA143XCA-7-F application, or DDTA143XCA-7-F equivalent, key selection criteria include verified input voltage thresholds (V_IN(on) = −3.0 V), guaranteed saturation voltage (V_CE(sat) ≤ −0.3 V), resistor tolerance (±30% on R1), resistance ratio tolerance (±20% on R2/R1), and thermal performance (R_θJA = 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 components. Its R1 ≠ R2 topology provides asymmetric switching thresholds for improved noise immunity in digital signal conditioning.

The SOT-323 package supports surface-mount assembly on FR4 PCBs with recommended pad layout AP02001, delivering 200 mW power dissipation and operation across −55 °C to +150 °C. The "Green" molding compound meets UL 94V-0 flammability rating and J-STD-020C Level 1 moisture sensitivity.

Key Specifications

Pinout & Package

Package: SOT-323 - ultra-small surface-mount plastic package (2.00–2.20 mm length, 1.15–1.35 mm width, 0.25–0.40 mm thickness), lead-free matte tin plating, UL 94V-0 rated, moisture sensitivity Level 1.

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, this part offers faster switching due to lower R2 and higher effective base drive; versus DDTC143XCA-7-F, it preserves PNP logic polarity and pin compatibility, avoiding redesign of gate-drive paths and firmware logic inversion.

Availability

DDTA143XCA-7-F is available at Aetrix Electronics and suitable for industrial sensor interfaces, automotive body control modules, and consumer appliance control boards requiring stable component supply, consistent parametric performance, and long-term lifecycle support.

Supply support for DDTA143XCA-7-F 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, serving industrial, computing, communications, and consumer markets with high-reliability, environmentally compliant components.

This device belongs to the DDTA (R1≠R2 Series) pre-biased transistor family, designed specifically for simplified digital interface and logic-level translation in compact, cost-sensitive PCB designs where board space and assembly yield are critical.

FAQ

What is the absolute maximum input voltage for DDTA143XCA-7-F?

The absolute maximum input voltage (V_IN) is specified as +7 V to −20 V at T_A = 25 °C. This range reflects safe operation under transient overvoltage conditions and ensures robustness against ESD and supply rail coupling. Exceeding −20 V risks irreversible breakdown of the internal R1 resistor or base-emitter junction.

Can DDTA143XCA-7-F be used in linear amplifier configurations?

No-it is optimized for saturated switching operation, not linear amplification. Its R1/R2 bias network fixes the base operating point, and the datasheet provides no linearity, distortion, or small-signal gain specifications. Use discrete transistors or dedicated amplifier ICs for analog signal conditioning.

Is the SOT-323 package thermally adequate for continuous 100 mA operation?

At full rated I_O = −100 mA and V_CE(sat) ≈ −0.25 V, power dissipation is ~25 mW-well below the 200 mW P_D limit. With R_θJA = 625 °C/W, junction rise is ~16 °C above ambient, making it thermally sufficient for continuous operation on standard FR4 without heatsinking.

How does resistor tolerance affect switching performance?

R1 tolerance of ±30% directly impacts input current and thus switching speed and saturation depth; R2/R1 ratio tolerance of ±20% affects threshold stability and noise margin. These tolerances are factored into the min/max V_IN(on) and h_FE specs-designs must accommodate worst-case bounds rather than typical values.