onsemi 2SB1124S-TD-E

Overview

2SB1124S-TD-E from onsemi is a PNP bipolar junction transistor in PCP (SOT-89) package, rated for –50 V V_CEO, –3 A I_C, and 500 mW P_C at T_a=25°C, with low V_CE(sat) of –0.35 V at I_C=–2 A/I_B=–100 mA. It serves as a high-current switching element in relay drivers and voltage regulators.

For engineers reviewing the 2SB1124S-TD-E datasheet, pinout, applications, or equivalent options, key selection criteria include verified PNP polarity, SC-62/PCP mechanical compatibility, guaranteed h_FE ≥100 at I_C=–100 mA, f_T = 150 MHz, and Pb-free TD reel packaging.

Technical Context

This PNP transistor uses FBET and MBIT processes to achieve low saturation voltage and fast switching: t_on = 70 ns, t_stg = 450 ns, t_f = 35 ns. Its ASO (Safe Operating Area) supports pulsed I_CP = –6 A at 100 ms, enabling robust operation in inductive load switching.

Designed for DC and pulse operation up to T_j = 150°C, it delivers stable h_FE across temperature (25°C to 75°C), with V_(BR)CEO = –50 V and V_(BR)CBO = –60 V ensuring reliable breakdown margin in regulator feedback paths.

Key Specifications

Pinout & Package

2SB1124S-TD-E is housed in a PCP package (JEITA SC-62 / JEDEC SOT-89), with 3 terminals mounted on a thermally enhanced ceramic substrate footprint. The package measures 4.5 mm × 2.5 mm × 1.6 mm and features gull-wing leads for surface-mount reflow assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP bipolar transistor applications.

Compared with 2SB1124S-TD-E, 2SB1218S-TD-E trades current capability for voltage headroom, while MJD2955RLG sacrifices switching speed and board area for raw power handling - making 2SB1124S-TD-E optimal for compact, medium-power PNP switching where thermal and timing constraints dominate.

Availability

2SB1124S-TD-E is available at Aetrix Electronics and suitable for relay drivers, voltage regulators, and lamp drivers requiring stable component supply, RoHS-compliant packaging, and consistent h_FE binning across production lots.

Supply support for 2SB1124S-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 (Semiconductor Components Industries, LLC) is a global semiconductor supplier focused on energy-efficient technologies for automotive, industrial, cloud, and IoT applications.

The 2SB1124S-TD-E belongs to onsemi's general-purpose bipolar transistor product line, engineered for cost-sensitive, high-reliability discrete switching in power management and interface circuits.

FAQ

What is the maximum continuous collector current rating for the 2SB1124S-TD-E?

The 2SB1124S-TD-E has a maximum continuous collector current I_C of –3 A at T_a = 25°C when mounted on a ceramic substrate (250 mm² × 0.8 mm). Derating applies above 25°C ambient, with P_C dropping to zero at T_a = 150°C. This rating is confirmed in the Absolute Maximum Ratings table of the official onsemi datasheet No.2019-2/7.

Is the 2SB1124S-TD-E pin-compatible with other variants in the 2SB1124 family?

Yes, all 2SB1124S-TD-E, 2SB1124S-TD-H, 2SB1124T-TD-E, and 2SB1124T-TD-H share identical PCP (SOT-89) package dimensions and pinout: Pin 1 = Base, Pin 2 = Collector, Pin 3 = Emitter. Differences are limited to h_FE rank (S vs. T) and environmental compliance (Pb-free vs. Pb-free/halogen-free), not electrical or mechanical interface.

What is the typical gain-bandwidth product (f_T) of the 2SB1124S-TD-E?

The 2SB1124S-TD-E has a guaranteed f_T of 150 MHz at V_CE = –10 V and I_C = –50 mA, as specified in the Electrical Characteristics table. This value is measured and documented in the onsemi datasheet No.2019-3/7 and enables reliable operation in high-speed switching applications up to several megahertz.

Does the 2SB1124S-TD-E require a heatsink for normal operation?

No, the 2SB1124S-TD-E is rated for 500 mW dissipation at T_a = 25°C on a ceramic substrate without external heatsink. At I_C = –2 A and V_CE(sat) = –0.35 V, power dissipation is ~0.7 W - exceeding the 500 mW rating. In such cases, thermal design must ensure junction temperature remains ≤150°C using PCB copper area or minimal heatsinking per the derating curve in Figure No.2019-5/7.

How does the h_FE ranking affect selection of the 2SB1124S-TD-E?

The "S" in 2SB1124S-TD-E denotes h_FE Rank S (140–280 at V_CE = –2 V, I_C = –100 mA), providing tighter DC gain control than Rank R (100–200) and better predictability than Rank T (200–400). This binning ensures consistent base drive requirements in production designs where gain variation must be minimized, such as in precision current sinks.