Diodes Incorporated ZTX692BSTOA

Overview

ZTX692BSTOA from Diodes Incorporated is an NPN silicon planar medium-power high-gain transistor designed for switching and linear amplification in low-voltage, moderate-current circuits. It delivers V_CEO = 70 V, h_FE = 400 at I_C = 500 mA, V_CE(sat) = 0.15 V (I_C = 0.1 A, I_B = 0.5 mA), and f_T = 150 MHz - enabling efficient relay and motor drive stages in battery-powered industrial controls.

For engineers reviewing the ZTX692BSTOA datasheet, ZTX692BSTOA pinout, ZTX692BSTOA application, or ZTX692BSTOA equivalent, key selection criteria include verified saturation voltage under pulsed load conditions, thermal resistance (R_th(j-amb) = 175 °C/W on 1-in² PCB copper), and gain linearity across I_C = 100 mA to 1 A at V_CE = 2 V.

Technical Context

This discrete NPN bipolar junction transistor operates with a maximum junction temperature of +200 °C and supports continuous collector current up to 1 A. Its low V_CE(sat) (0.15 V typical) and high h_FE (500 min at I_C = 100 mA) enable efficient Darlington pair configurations and reduce base drive requirements in switching applications.

The device features f_T = 150 MHz at I_C = 50 mA and V_CE = 5 V, with C_ibo = 200 pF and C_obo = 12 pF - confirming suitability for medium-frequency switching (e.g., PWM motor control up to ~50 kHz) while maintaining stable DC gain characteristics.

Key Specifications

Pinout & Package

Package: TO-92 (E-Line compatible, 3-pin plastic through-hole). Mounting requires ≥1 in² copper area for rated power dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN medium-power switching applications.

Compared with ZTX653BSTOA, ZTX692BSTOA offers +10 V headroom and +60% gain at 500 mA, improving noise immunity in relay interfaces; versus MJD112G, it trades 10× power capacity for TO-92 compatibility and lower system cost in sub-1 A applications.

Availability

ZTX692BSTOA is available at Aetrix Electronics and suitable for relay drivers, battery-powered motor control, Darlington amplifier stages, and industrial sensor interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ZTX692BSTOA 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

Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal solutions for industrial, computing, consumer, and communications markets.

ZTX692BSTOA belongs to the ZTX series of high-gain, medium-power bipolar transistors engineered for robust switching and amplification in cost-sensitive, thermally constrained applications such as portable equipment and factory automation modules.

FAQ

What is the maximum safe continuous collector current for ZTX692BSTOA at 75°C ambient?

At T_amb = 75 °C, derating begins at 25 °C using R_th(j-amb) = 175 °C/W. With T_j(max) = 200 °C, allowable ΔT = 125 °C → P_tot = 125 / 175 ≈ 0.714 W. Using V_CE(sat) ≈ 0.3 V at I_C = 1 A, actual dissipation at 1 A is ~0.3 W - so 1 A is thermally viable if copper area meets spec. Full 1 A rating holds only with ≥1 in² copper.

Can ZTX692BSTOA replace BC337-40 in a 5 V microcontroller-driven relay circuit?

Yes - ZTX692BSTOA has higher V_CEO (70 V vs. 45 V), higher h_FE (400 vs. 250), and lower V_CE(sat) (0.15 V vs. 0.2 V), making it a superior drop-in replacement. Pinout (E-B-C) matches BC337-40, and TO-92 footprint is identical. No layout change needed.

Is ZTX692BSTOA suitable for linear amplifier applications?

Yes - its h_FE remains stable from I_C = 10 mA to 1 A at V_CE = 2 V, and V_CE(sat) is well-characterized. However, f_T = 150 MHz and C_obo = 12 pF limit small-signal bandwidth to ~10 MHz; it is appropriate for audio preamps or sensor signal conditioning but not RF amplification.

Does ZTX692BSTOA require a heatsink for 500 mA continuous operation?

No - with 1 in² copper pad per Diodes' datasheet condition, R_th(j-amb) = 175 °C/W yields ~53 °C rise at P_tot = 0.3 W (I_C = 500 mA, V_CE(sat) ≈ 0.6 V), keeping T_j < 100 °C at 45 °C ambient. A heatsink is unnecessary unless ambient exceeds 70 °C or copper area is reduced.