NXP Semiconductors BC556B,116

Overview

BC556B,116 from NXP Semiconductors is a PNP general-purpose bipolar junction transistor in TO-92 (SOT54) package, rated for −65 V V_CEO, −80 V V_CBO, −100 mA I_C, with h_FE range 220–475 at I_C = −2 mA, and V_CEsat ≤ −300 mV at I_C = −10 mA / I_B = −0.5 mA. It serves as a low-voltage, low-current switch or linear amplifier in discrete analog and digital interface circuits.

For engineers reviewing the BC556B,116 datasheet, BC556B,116 pinout, BC556B,116 application, or BC556B,116 equivalent, key selection criteria include verified PNP polarity, TO-92 mechanical compatibility, DC current gain binning (B-grade), absolute maximum ratings under IEC 60134, and thermal resistance of 250 K/W on FR4 PCB.

Technical Context

The BC556B,116 operates as a silicon PNP BJT with base-controlled minority-carrier injection into the emitter, enabling current amplification and switching via forward-active or saturation biasing. Its design targets cost-sensitive, non-critical analog and logic-level interfacing where precise gain matching or high-frequency operation is not required.

It exhibits temperature-dependent V_BE (−2 mV/K) and V_BEsat (−1.7 mV/K), supports pulsed peak collector current up to −200 mA, and delivers f_T ≥ 100 MHz at V_CE = −5 V and I_C = −10 mA - sufficient for audio-frequency and low-speed digital signal conditioning.

Key Specifications

Pinout & Package

BC556B,116 is housed in a plastic single-ended leaded (through-hole) TO-92 package, also designated SOT54 or SC-43A, with 3 leads and JEDEC-standard outline dimensions (L = 14.5 mm, D = 4.8 mm, E = 4.2 mm, e = 2.54 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC556B,116, BC557B,116 offers identical gain binning but reduced voltage rating, while MMBT5551LT1G provides higher voltage capability in SMT form but demands circuit re-engineering due to polarity and package mismatch.

Availability

BC556B,116 is available at Aetrix Electronics and suitable for audio signal amplification, level-shifting interfaces, discrete power switching, and current mirror reference circuits requiring stable component supply and consistent B-grade h_FE performance.

Supply support for BC556B,116 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and consumer applications.

The BC556B,116 belongs to NXP's legacy discrete transistor product line, engineered for cost-effective, reliable general-purpose switching and amplification in through-hole assembled equipment.

FAQ

What is the maximum collector-emitter voltage rating for BC556B,116?

The BC556B,116 has a maximum collector-emitter voltage (V_CEO) rating of −65 V with the base open, per IEC 60134 Absolute Maximum Ratings. This defines the highest reverse bias the transistor can withstand in common-emitter configuration without breakdown. Exceeding this value risks permanent damage, and derating is recommended for long-term reliability in production designs using BC556B,116.

Is BC556B,116 pin-compatible with BC546 or BC547?

No - BC556B,116 is a PNP transistor, while BC546 and BC547 are NPN devices with complementary functionality but identical TO-92 pinout (emitter-base-collector = pins 1-2-3). Though mechanically compatible, they are electrically opposite in polarity and cannot be substituted without circuit modification. The BC556B,116's pinout remains emitter (1), base (2), collector (3), matching the BC546/BC547 physical layout but reversing current flow direction.

What does the 'B' suffix indicate in BC556B,116?

The 'B' in BC556B,116 denotes the h_FE (DC current gain) bin: specifically, a guaranteed range of 220–475 at I_C = −2 mA and V_CE = −5 V. This binning allows designers to select transistors with tighter gain tolerance than the broader A-grade (125–250) or C-grade (420–800) variants, improving predictability in base-drive calculations for BC556B,116-based amplifiers and switches.

Can BC556B,116 be used in surface-mount designs?

No - BC556B,116 is packaged exclusively in the through-hole TO-92 (SOT54) format and lacks an SMT variant. For surface-mount equivalents, engineers must select alternative PNP transistors such as the PBSS4041T (SOT-23) or MMBT3906 (SOT-23), which differ in pinout, gain binning, and thermal characteristics. Direct substitution of BC556B,116 into SMT layouts is not feasible without adapter hardware or PCB redesign.

What is the thermal resistance junction-to-ambient for BC556B,116?

The thermal resistance from junction to ambient (R_th(j-a)) for BC556B,116 is 250 K/W when mounted on a standard FR4 printed-circuit board, as specified in the NXP datasheet. This value assumes no added heatsinking and defines the temperature rise per watt of dissipated power - critical for calculating safe operating area and derating curves when designing circuits that operate BC556B,116 near its 500 mW total power limit.