Diodes Incorporated DDTC124XCA-7-F

Overview

DDTC124XCA-7-F from Diodes Incorporated is an NPN pre-biased small-signal transistor in SOT23 package with integrated bias resistors R1 = 22 kΩ and R2 = 47 kΩ, rated for 50 V V_CEO, 50 mA I_O, and 200 mW power dissipation. It operates across –55°C to +150°C and is AEC-Q101 qualified for automotive signal switching applications such as LED driver control and logic-level translation.

For engineers reviewing the DDTC124XCA-7-F datasheet, DDTC124XCA-7-F pinout, DDTC124XCA-7-F application, or DDTC124XCA-7-F equivalent, key selection criteria include input voltage range (–10 V to +40 V), DC current gain (G_L = 68 at V_CE = 5 V, I_O = 5 mA), saturation voltage (V_CE(SAT) ≤ 0.3 V), resistor tolerance (±30% on R1, ±20% on R2/R1 ratio), and thermal resistance (R_θJA = 625 °C/W).

Technical Context

This device integrates two precision bias resistors (R1 ≠ R2) to configure a fixed-current-input, open-collector output stage optimized for digital interface buffering and level-shifting. Its internal inverter topology enables direct connection to CMOS/TTL outputs without external base resistors.

The transistor supports rail-to-rail input operation (–10 V to +40 V) and delivers stable 50 mA output current into saturated switching loads. Its 250 MHz f_T and low V_CE(SAT) ensure fast edge response and minimal conduction loss in high-frequency digital control paths.

Key Specifications

Pinout & Package

Package: SOT23 - Surface-mount plastic case (2.9 mm × 1.35 mm × 1.0 mm), UL 94V-0 rated, moisture sensitivity Level 1, matte tin-plated leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DDTC124XCA-7-F, DDTC123YCA-7-F offers faster turn-on at lower voltages but reduced input voltage headroom, while DDTC143XCA-7-F provides broader transient tolerance at the cost of lower DC gain (G_L = 30 vs. 68) and higher R1 tolerance impact on bias stability.

Availability

DDTC124XCA-7-F is available at Aetrix Electronics and suitable for automotive lighting control, industrial PLC I/O conditioning, and medical diagnostic equipment requiring stable component supply with AEC-Q101 compliance and long-term lifecycle support.

Supply support for DDTC124XCA-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, specializing in high-reliability components for automotive, industrial, and consumer markets with ISO/TS 16949 and IATF 16949 certification.

This part belongs to the DDTC (R1≠R2 Series) CA family of pre-biased transistors designed specifically for simplified digital interface design in space-constrained, high-volume applications where board area and assembly cost are critical.

FAQ

What is the function of the R1 ≠ R2 configuration in DDTC124XCA-7-F?

The asymmetric resistor network (R1 = 22 kΩ, R2 = 47 kΩ) creates a defined base current path that ensures predictable transistor turn-on behavior without external components. This configuration provides stable DC biasing for digital switching, suppresses false triggering from noise, and maintains consistent gain across temperature and process variation.

Can DDTC124XCA-7-F be used in place of a standard NPN transistor like BC847?

Yes, but only in open-collector configurations where the base is driven through the internal R1/R2 network. Unlike BC847, it lacks a direct base terminal - the base is internally accessible only via the resistor junction at Pin 2. External base drive or linear amplification is not supported due to the fixed bias architecture.

What does the "-7-F" suffix indicate in the part number?

The "-7-F" denotes tape-and-reel packaging: 7-inch reel diameter, 8 mm tape width, and 3,000 units per reel. The "F" confirms full RoHS compliance and halogen-free ("Green") construction per Diodes Incorporated's specification, with matte tin plating and J-STD-020 Level 1 moisture sensitivity rating.

Is thermal derating required for continuous 50 mA operation?

Yes - at 25°C ambient, full 50 mA output is permissible only if power dissipation remains ≤200 mW. With V_CE(SAT) ≈ 0.25 V, P_D ≈ 12.5 mW, well within limit. However, above 70°C ambient, derating begins per the 625 °C/W R_θJA; at 100°C ambient, max safe I_O drops to ~32 mA to maintain T_J ≤ 150°C.