The BDX53B is an NPN Darlington transistor in a TO-220 through-hole package, rated for 80 V collector-emitter breakdown and 8 A continuous collector current. The Darlington pair gives a minimum DC current gain of 750 at 3 A collector current and 3 V VCE, so the base drive requirement stays low — about 12 mA base current to saturate the output at 3 A. That gain margin means a simple microcontroller GPIO through a resistor can drive it, no separate driver stage needed. Maximum power dissipation is 60 W, which sets the thermal budget. In a TO-220 package that figure assumes the device is bolted to an infinite heatsink — real-world derating depends on the thermal interface and ambient.
BDX53B NPN Darlington Transistor, 80V 8A TO-220
MPNBDX53B
End of Life
BDX53B NPN Darlington transistor, 80 V VCEO, 8 A Ic, 60 W max, hFE 750 min at 3 A, TO-220-3, through hole, 150°C junction temperature.
$1.3Ref. price · indicative, final on quote
PackagingTO-220-3
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026
Specifications
| Parameter | Value |
|---|---|
| Mounting | Through Hole |
| FET type | NPN - Darlington |
| Voltage - collector emitter breakdown | 80 V |
| Current - collector (Ic) | 8 A |
| Current - collector cutoff | 500µA |
| DC current gain (hFE) (Min) @ ic, vce | 750 @ 3A, 3V |
| Power - max | 60 W |
| Operating temperature | 150°C (TJ) |
| Package | Tube |
| Case | TO-220-3 |
| Vce saturation (Max) @ ib, ic | 2V @ 12mA, 3A |
Product details
Frequently asked questions
Is BDX53B equivalent to TIP122?
Both are NPN Darlington transistors in TO-220 packages with similar voltage and current ratings. The TIP122 is rated 100 V VCEO and 5 A Ic, while the BDX53B is rated 80 V VCEO and 8 A Ic. The BDX53B carries a higher continuous current rating but a lower voltage rating. Pin-compatible in the same TO-220 footprint, but the voltage and current limits differ — check the load conditions before substituting.