All Transistor Equivalent Book [work] Jun 2026

At its core, a transistor equivalent book is a . It lists thousands of original manufacturer part numbers (e.g., 2N2222, BC547, 2SC945) and suggests one or more substitute parts with similar electrical characteristics.

| If you have... | Do NOT substitute with... | Why | | :--- | :--- | :--- | | A (TIP120) | A single BJT (2N3904) | The base current will be 100x too low. | | A JFET (2N5457) | Any MOSFET or BJT | JFETs are depletion-mode; MOSFETs are enhancement-mode. Not interchangeable. | | A Matched pair (LM394) | Two random individual transistors | Vbe mismatch will cause DC offset. | | A High-voltage CRT driver (BU508A) | A standard power transistor (TIP31) | The standard part will instantly breakdown at 1500V. | | A RF transistor (2SC1971) | A general purpose transistor | Low ft and high Cob will kill RF power output. | all transistor equivalent book

While not just for equivalents, it provides authoritative details on substitutions and common problems for transistors. Towers' International Transistor Selector At its core, a transistor equivalent book is a

Ensure the substitute is the same type (NPN or PNP). Check VCEOcap V sub cap C cap E cap O end-sub | Do NOT substitute with