Nexperia USA Inc. PDTB123YUX

Overview

PDTB123YUX from Nexperia is a PNP resistor-equipped transistor (RET) in SOT323 (SC-70) package, designed for digital switching applications requiring integrated biasing. It delivers −500 mA output current, features 2.2 kΩ input bias resistor (R1) and 10 kΩ base-emitter resistor (R2), and supports operation up to 175 °C ambient temperature - ideal for automotive body control modules and industrial I/O drivers.

For engineers reviewing the PDTB123YUX datasheet, PDTB123YUX pinout, PDTB123YUX application, or PDTB123YUX equivalent, key selection criteria include its ±10 % R2/R1 ratio tolerance (4.1–5.0), −1.0 V typical on-state input voltage at −20 mA, −100 mV collector-emitter saturation voltage, and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

This device integrates a PNP bipolar transistor with two monolithically embedded precision resistors: R1 (2.2 kΩ) connects the input terminal to the base, while R2 (10 kΩ) ties base to emitter, enabling single-resistor drive from logic-level sources. Its fixed R2/R1 ratio of 4.55 ensures stable DC current gain (h_FE = 70 typ. at −50 mA) without external bias network design.

Rated for −50 V V_CEO and −500 mA I_O, it operates across −55 °C to +175 °C ambient, with thermal resistance R_th(j-a) of 353 K/W on 4-layer FR4 PCB. The built-in structure eliminates discrete resistor placement, reducing board area and assembly steps in high-density digital interface circuits.

Key Specifications

Pinout & Package

SOT323 (SC-70) plastic surface-mounted package: 1.35 mm × 1.15 mm × 0.45 mm footprint, 3-terminal leadframe with gull-wing leads. Optimized for reflow soldering per JEDEC J-STD-020; thermal pad not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PDTB123EU, PDTB123YUX offers superior noise immunity due to higher R2 value and tighter R2/R1 ratio, making it preferred in electrically noisy automotive cabins; versus BC807-40, it trades raw gain for integration, reliability, and reduced layout complexity in volume production.

Availability

PDTB123YUX is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLC output stages, consumer appliance interfaces, and medical diagnostic equipment requiring stable component supply and AEC-Q101 compliance.

Supply support for PDTB123YUX 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

Nexperia is a global semiconductor expert focused on essential efficiency technologies, delivering high-performance, reliable discrete and logic devices for automotive, industrial, and consumer markets.

PDTB123YUX belongs to the PDTB1xxxU series of resistor-equipped transistors, engineered specifically to simplify digital interface design in space-constrained, high-reliability applications - especially where AEC-Q101 qualification and thermal robustness are mandatory.

FAQ

What is the maximum allowable input voltage (VI) for PDTB123YUX?

The absolute maximum input voltage is −12 V (negative polarity) and +5 V (positive polarity), per Table 6 limiting values. Exceeding −12 V risks permanent damage to the internal R1 resistor and transistor junction. For reliable operation, keep VI within −1.4 V to −0.5 V (on-state) or −0.65 V to −0.4 V (off-state) as specified in Table 8 characteristics.

Can PDTB123YUX replace BC817-40 in existing designs?

Direct replacement is not recommended without circuit validation. BC817-40 is an NPN transistor requiring external biasing and opposite polarity drive; PDTB123YUX is a PNP RET with integrated resistors and negative-voltage logic interface. Functional equivalence requires inverting the control signal and verifying load configuration compatibility.

How does the R2/R1 ratio of 4.55 affect switching behavior?

A ratio of 4.55 ensures strong base-emitter forward bias during turn-on while maintaining sufficient reverse bias for clean turn-off. This yields predictable h_FE ≈ 70 at −50 mA and suppresses leakage-induced false triggering - particularly valuable in high-noise automotive CAN bus environments where stray coupling could otherwise activate the device.

Is thermal derating required when operating at 125 °C ambient?

Yes. At T_amb = 125 °C, the maximum allowable continuous output current must be reduced from −500 mA to approximately −220 mA, based on the 353 K/W junction-to-ambient thermal resistance and 175 °C T_j limit. Derating follows linear power reduction: P_tot = (175 − T_amb) / R_th(j-a).