onsemi 2SC4548D-TD-E

Overview

2SC4548D-TD-E from onsemi is an NPN epitaxial planar silicon transistor designed for high-voltage driver applications, featuring V_CEO = –400 V, I_C = –200 mA, h_FE = 100–200 (Rank E), f_T = 70 MHz, and V_CE(sat) = –0.6 V at I_C = –50 mA / I_B = –5 mA - used in horizontal deflection output stages of CRT displays.

For engineers reviewing the 2SC4548D-TD-E datasheet, pinout, applications, or equivalent options, key selection criteria include high-voltage blocking capability, fast switching (t_on = 0.25 µs, t_off = 5.0 µs), h_FE linearity across temperature, low saturation voltage, and ceramic-board thermal mounting requirements.

Technical Context

This NPN transistor employs onsemi's MBIT process to achieve stable h_FE linearity and high breakdown voltage. Its design targets high-voltage switching with controlled gain-bandwidth trade-offs: f_T = 70 MHz ensures adequate RF response while maintaining robust DC current gain (h_FE min = 100 at I_C = –50 mA).

Switching performance is characterized under defined test conditions: V_CC = 150 V, I_C = 50 mA, R_L = 3 kΩ, R_B = 200 Ω. The device exhibits low output capacitance (C_ob = 4 pF) and reverse transfer capacitance (C_re = 3 pF) at V_CB = –30 V, supporting efficient energy transfer in flyback and deflection circuits.

Key Specifications

Pinout & Package

2SC4548D-TD-E is housed in a TO-92MOD (or TO-92S) plastic package with 3-terminal through-hole configuration, optimized for ceramic board mounting (250 mm² × 0.8 mm). Pin assignment follows standard JEDEC TO-92 orientation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage NPN transistor applications.

Compared with 2SC4548D-TD-E, the 2SC4548E-TD-E offers identical performance in tape-and-reel form, while MJD44H11T4 provides higher current capacity at significantly reduced voltage rating - making it unsuitable for CRT horizontal output but viable for industrial 48 V–72 V flyback designs.

Availability

2SC4548D-TD-E is available at Aetrix Electronics and suitable for CRT display repair, legacy flyback converter refurbishment, and high-voltage analog amplifier replacement requiring stable component supply and long-lifecycle support.

Supply support for 2SC4548D-TD-E 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

onsemi (formerly ON Semiconductor) is a global semiconductor manufacturer specializing in energy-efficient power, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The 2SC4548D-TD-E belongs to onsemi's legacy high-voltage bipolar transistor product line, engineered specifically for reliability-critical horizontal deflection and flyback switching in analog video equipment.

FAQ

What is the maximum collector-emitter voltage rating for the 2SC4548D-TD-E?

The 2SC4548D-TD-E has a guaranteed V_CEO rating of –400 V at I_C = –1 mA with R_BE = ∞. This rating is validated per onsemi's absolute maximum specifications and applies under continuous DC and repetitive pulse conditions typical in CRT horizontal output circuits. The 2SC4548D-TD-E maintains this rating across its specified operating temperature range.

Is the 2SC4548D-TD-E pin-compatible with the 2SA1740 PNP counterpart?

No - the 2SC4548D-TD-E is an NPN transistor, while the 2SA1740 is a complementary PNP device. Though they share the same TO-92MOD package outline and terminal spacing, their pin assignments are reversed: 2SC4548D-TD-E uses E-B-C order, whereas 2SA1740 uses C-B-E. Direct substitution without circuit redesign will cause functional failure.

What does the 'D' and 'E' suffix in 2SC4548D-TD-E indicate?

The 'D' and 'E' denote h_FE rank classifications per onsemi's datasheet: 'D' = h_FE 60–120, 'E' = h_FE 100–200 at V_CE = –10 V and I_C = –50 mA. The full marking '2SC4548D-TD-E' confirms this unit is Rank E, supplied in tape-and-reel (TD-E) packaging. The 'CN' marking on the device body further identifies it as a 2SC4548.

Can the 2SC4548D-TD-E be mounted on FR-4 PCB instead of ceramic board?

No - the 2SC4548D-TD-E's thermal specification (P_C = 1.3 W) is explicitly rated for mounting on a 250 mm² × 0.8 mm ceramic board. FR-4 has significantly lower thermal conductivity; using it would cause junction temperature to exceed 150°C under rated load, risking premature failure. Thermal vias and copper pours on FR-4 do not compensate for the required ceramic substrate performance.

What is the typical gain-bandwidth product (f_T) of the 2SC4548D-TD-E?

The 2SC4548D-TD-E has a typical f_T of 70 MHz, measured at V_CE = –30 V and I_C = –10 mA. This value is confirmed in the onsemi datasheet and reflects the device's small-signal frequency limit - sufficient for horizontal deflection frequencies (~15.7 kHz) with wide bandwidth margin, but not intended for RF amplification above 10 MHz.