NXP Semiconductors PN2907A,126

Overview

PN2907A from NXP Semiconductors is a PNP bipolar junction transistor designed for general-purpose switching and linear amplification in low-voltage, medium-current applications. It supports −60 V collector-base and collector-emitter voltages, −600 mA DC collector current, 500 mW power dissipation at 25 °C ambient, and delivers DC current gain (h_FE) of 100–300 at −150 mA/−10 V. It is commonly used in relay drivers, LED switches, and discrete logic-level inverters.

For engineers reviewing the PN2907A datasheet, PN2907A pinout, PN2907A application, or PN2907A equivalent, key selection considerations include its TO-92 (SOT54/SC-43A) through-hole package, verified PNP switching performance, −365 ns turn-off time, −200 MHz transition frequency, and complementary pairing with PN2222A in push-pull configurations.

Technical Context

The PN2907A operates as a silicon-based PNP BJT with fixed emitter-base and collector-base junction structures optimized for stable DC gain and fast switching. Its h_FE varies from 75 to 300 across collector currents from 0.1 mA to 500 mA, and saturation voltages are characterized at −400 mV (IC = −150 mA, IB = −15 mA) and −1.6 V (IC = −500 mA, IB = −50 mA).

Thermal resistance from junction-to-ambient is 250 K/W when mounted on FR4 PCB, limiting continuous operation under high-power conditions without heatsinking. Switching behavior is defined by measured times: 40 ns turn-on, 365 ns turn-off, and 300 ns storage time - all validated at −150 mA conduction and ±15 mA base drive.

Key Specifications

Pinout & Package

PN2907A is housed in a plastic single-ended leaded (through-hole) TO-92 package, standardized as SOT54 and SC-43A, with 3 leads and JEDEC-compliant outline dimensions (L = 14.5 mm, D = 4.8 mm, e = 2.54 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with PN2907A, MMBT2907A trades package form factor and thermal capacity for compactness, while BC557 emphasizes gain and noise performance at the expense of breakdown voltage and bandwidth - making PN2907A the balanced choice for robust, general-purpose PNP switching.

Availability

PN2907A is available at Aetrix Electronics and suitable for relay driver circuits, LED current switches, digital level shifters, and analog signal inverters requiring stable component supply and long-term obsolescence support.

Supply support for PN2907A 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.

PN2907A belongs to NXP's legacy discrete transistor product line, engineered for reliability in general-purpose analog and switching functions across industrial control, power management, and interface circuitry.

FAQ

What is the maximum collector-emitter voltage rating for PN2907A?

The PN2907A has a maximum collector-emitter voltage (V_CEO) rating of −60 V under open-base conditions. This value represents the absolute maximum reverse bias the transistor can withstand before breakdown. Exceeding this voltage risks permanent damage. The PN2907A datasheet confirms this limit applies across the full operating temperature range and is validated per IEC 60134 Absolute Maximum Ratings.

Is PN2907A pin-compatible with PN2222A?

No, PN2907A is not pin-compatible with PN2222A - they share the same TO-92 package outline and lead spacing, but their pin assignments differ. PN2907A uses pin 1 = collector, pin 2 = base, pin 3 = emitter; PN2222A uses pin 1 = emitter, pin 2 = base, pin 3 = collector. Direct substitution without PCB modification will result in incorrect polarity and circuit failure. Always verify pinout before interchanging.

What is the typical DC current gain (hFE) of PN2907A at 150 mA collector current?

The typical DC current gain (h_FE) of PN2907A at V_CE = −10 V and I_C = −150 mA is 200, with a guaranteed minimum of 100 and maximum of 300. This gain range is confirmed in the "Characteristics" section of the official NXP datasheet and reflects stable amplification performance under moderate load conditions suitable for switching and linear operation.

Can PN2907A be used in RF amplifier applications?

Yes, PN2907A can be used in low-frequency RF amplifier applications up to approximately 20 MHz due to its 200 MHz transition frequency (f_T). However, it is not optimized for RF - its 8 pF collector capacitance and lack of specified noise figure or S-parameters limit use in sensitive receiver front-ends. It is best suited for broadband AF amplifiers, oscillator buffers, or harmonic generators below 30 MHz.

What thermal resistance does PN2907A exhibit when mounted on FR4 PCB?

When mounted on a standard FR4 printed-circuit board without heatsinking, PN2907A exhibits a junction-to-ambient thermal resistance (R_th(j-a)) of 250 K/W. This value means that at 500 mW power dissipation, the junction temperature rises 125 °C above ambient - requiring careful thermal design to stay within the 150 °C maximum junction temperature limit. Derating is necessary above 25 °C ambient.