onsemi KSA1182YMTF

Overview

KSA1182YMTF from ON Semiconductor (formerly Fairchild) is a PNP epitaxial silicon transistor designed for low-frequency power amplification and switching in compact consumer and industrial circuits, with V_CEO = −30 V, I_C = −500 mA, P_C = 150 mW, h_FE = 120–240 (Y-grade), and SOT-23 package.

For engineers reviewing the KSA1182YMTF datasheet, pinout, applications, or equivalent options, this page delivers verified electrical ratings, terminal roles, thermal limits, complementary pairing context with KSC2859, and real-world use cases in audio preamp stages and relay drivers.

Technical Context

This PNP bipolar junction transistor operates in linear amplification and saturated switching modes, with guaranteed h_FE ≥120 at I_C = −100 mA and V_CE = −1 V, and f_T = 200 MHz enabling stable gain up to low-MHz signal bands. Its V_CE(sat) ≤ −0.25 V at I_C = −100 mA / I_B = −10 mA supports efficient low-voltage switching.

The device features low leakage (I_CBO, I_EBO ≤ −0.1 µA), tight Cob = 13 pF at V_CB = −6 V, and junction temperature rating up to 150°C - making it suitable for thermally constrained PCB layouts where thermal derating must be applied above 25°C ambient.

Key Specifications

Pinout & Package

SOT-23 surface-mount package with gull-wing leads; 1.90 mm × 1.30 mm footprint, 0.95 mm height, and JEDEC-standard 3-pin configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBT3906LT1G and BC807-40, the KSA1182YMTF offers tighter h_FE binning at high current, optimized V_CE(sat) for 100–400 mA loads, and documented complementary pairing with KSC2859 - making it preferred for matched dual-transistor amplifier and driver designs.

Availability

KSA1182YMTF is available at Aetrix Electronics and suitable for audio pre-amplifier stages, DC relay drivers, LED constant-current sinks, and level-shifting interfaces requiring stable component supply and consistent Y-grade gain performance.

Supply support for KSA1182YMTF 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

ON Semiconductor (acquired Fairchild Semiconductor in 2016) is a global supplier of energy-efficient semiconductor components for automotive, industrial, cloud computing, and IoT applications.

The KSA1182YMTF belongs to Fairchild's legacy general-purpose bipolar transistor family, engineered specifically for low-frequency linear amplification and robust switching in space-constrained consumer electronics and industrial controls.

FAQ

What is the maximum continuous collector current rating for KSA1182YMTF?

The KSA1182YMTF has a maximum continuous collector current (I_C) rating of −500 mA at T_A = 25°C. Derating is required above ambient temperatures - for example, at 70°C ambient, usable I_C drops to approximately −350 mA due to its 150 mW power dissipation limit and thermal resistance characteristics. Always verify junction temperature in final layout using θ_JA from the datasheet.

Is KSA1182YMTF pin-compatible with other SOT-23 PNP transistors like MMBT3906?

Yes, KSA1182YMTF uses standard SOT-23 pinout (1=Base, 2=Emitter, 3=Collector), matching MMBT3906 and BC807 series. However, direct substitution requires verification of h_FE, V_CE(sat), and thermal limits - KSA1182YMTF's Y-grade h_FE (120–240) and −500 mA rating differ from MMBT3906's −200 mA limit and broader h_FE range.

What does the "Y" in KSA1182YMTF signify?

The "Y" in KSA1182YMTF denotes the h_FE gain bin: guaranteed DC current gain of 120–240 at V_CE = −6 V and I_C = −400 mA. This tighter specification enables predictable biasing in production amplifiers without manual gain sorting or feedback trimming, distinguishing it from standard "O"-grade (70–140) variants.

Can KSA1182YMTF be used in switching power supply circuits?

KSA1182YMTF is not recommended for high-frequency switching power supplies due to its 200 MHz f_T and 150 mW power limit - insufficient for typical PWM controller drive or synchronous rectification. It is qualified for low-frequency (<100 kHz) auxiliary bias supplies and discrete gate drivers where switching speed and power handling are modest.

Does KSA1182YMTF have an official replacement or second-source part?

No direct second-source part exists for KSA1182YMTF. ON Semiconductor maintains active supply, and the closest functional alternatives - such as BC807-40 or MMBT3906LT1G - require circuit validation due to differences in h_FE distribution, saturation voltage, and absolute maximum ratings. KSA1182YMTF remains the only Y-grade, −500 mA, SOT-23 PNP with documented complementarity to KSC2859.