This document describes the features and applications of the QSZ4 transistors, including low VCE(sat) and small package. The transistors have a silicon epitaxial planar structure. The QSZ4 model consists of two independent transistors and a diode, housed in a TSMT5 package.
The QSZ4 is a general‑purpose isolated transistor offered by ROHM for use in DC‑DC converters and motor drivers. It features a low collector‑emitter saturation voltage and a compact TSMT5 package.
The document lists absolute maximum ratings, electrical characteristics such as voltage limits, current ratings, transition frequency, and gain, as well as packaging specifications and application notes for designers.
| Collector‑base voltage (VCBO) | -30 V |
|---|---|
| Emitter‑base voltage (VEB0) | -6 V |
| Power dissipation (PD) | 1.25 W |
| Storage temperature range | -55 to +150 °C |
| Package | TSMT5 |
| Transition frequency (ft) | 280 MHz |
The QSZ4 is supplied in a TSMT5 surface‑mount package.
The transition frequency (ft) is specified as 280 MHz.