Diodes Incorporated ZTX795A

Overview

ZTX795A from Zetex Semiconductors (now Diodes Incorporated) is a PNP silicon planar medium-power high-gain bipolar junction transistor designed for linear amplification and switching in industrial power control stages. It delivers V_CEO = −140 V, h_FE = 250 at I_C = −0.2 A, and V_CE(sat) = −0.25 V at I_C = −500 mA / I_B = −50 mA, enabling robust operation in high-voltage DC-DC converter output stages and relay drivers.

For engineers reviewing the ZTX795A datasheet, ZTX795A pinout, ZTX795A application, or ZTX795A equivalent, key selection criteria include verified PNP high-voltage capability (−140 V), low saturation voltage under high current, thermal resistance of 116 °C/W on 1-inch² PCB copper, and TO-92 package compatibility with legacy E-Line footprints.

Technical Context

The ZTX795A operates as a medium-power PNP BJT optimized for stable DC gain across collector currents from −10 mA to −300 mA, with h_FE ranging from 800 (min at I_C = −10 mA) to 100 (min at I_C = −300 mA). Its f_T = 100 MHz supports moderate-speed switching up to ~10–20 MHz with controlled rise/fall times.

Thermal design relies on its R_th(j–amb)2 = 116 °C/W when mounted on ≥1 inch² PCB copper, and safe operating area (SOA) curves confirm pulsed capability up to I_C = −1 A with V_CE ≤ −50 V under 2% duty cycle. V_BE(sat) = −0.95 V at I_C = −500 mA ensures predictable base drive requirements.

Key Specifications

Pinout & Package

Package: TO-92 (E-Line compatible, 3-lead plastic case). Standard lead configuration with emitter (E), base (B), and collector (C) arranged in linear order per JEDEC TO-92 outline.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP high-voltage switching applications.

Compared with ZTX753, the ZTX795A offers 40 V higher blocking voltage and 34 °C/W lower thermal resistance-critical for compact 100 V designs. Versus MJD2955, it trades current capacity for PCB-mount convenience and voltage headroom, making it optimal for space-constrained medium-voltage switching.

Availability

ZTX795A is available at Aetrix Electronics and suitable for industrial DC-DC converters, high-voltage relay drivers, and analog signal amplifiers requiring stable component supply with long-lifecycle support.

Supply support for ZTX795A 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

Zetex Semiconductors, now part of Diodes Incorporated, specializes in high-performance discrete semiconductors for power management and signal conditioning.

The ZTX7xx series was developed for industrial-grade PNP switching and amplification where high V_CEO, low V_CE(sat), and TO-92 compatibility are essential-targeting legacy system upgrades and space-constrained power stages.

FAQ

Is ZTX795A RoHS compliant and halogen-free?

Yes, ZTX795A meets RoHS Directive 2011/65/EU and is halogen-free per IEC 61249-2-21. Diodes Incorporated's official documentation confirms compliance for all ZTX795A lots manufactured after April 2010, with full material declarations available upon request for qualifying orders.

Can ZTX795A replace BC327 in existing designs?

ZTX795A can replace BC327 only if the application operates below −45 V V_CE and does not require the BC327's higher h_FE at low currents. ZTX795A's −140 V rating and −0.25 V V_CE(sat) offer advantages in high-voltage designs, but its h_FE drops faster above −200 mA-verify gain and thermal margins in situ.

What is the maximum safe continuous collector current at 70°C ambient?

At T_amb = 70 °C, derating from P_tot = 1.5 W at 25 °C applies: ΔT = 45 °C × 5.7 mW/°C = 256.5 mW reduction → P_max = 1.2435 W. With V_CE(sat) ≈ −0.28 V at I_C = −0.5 A, max continuous I_C ≈ 0.44 A assuming worst-case V_CE(sat).

Does ZTX795A require a base resistor in switching applications?

Yes-a base resistor is mandatory to limit I_B and prevent thermal runaway. For I_C = −500 mA and h_FE = 250, minimum I_B = −2 mA is required; with V_BE(sat) = −0.95 V and 5 V drive, R_B ≈ 2 kΩ ensures reliable saturation while avoiding excessive base current.