# How do I test a diode for Reverse Breakdown Voltage on my curve tracer?

### 問題：

How do I test a diode for Reverse Breakdown Voltage on my curve tracer?

### 答案：

Reverse Breakdown Voltage - V(br)

What It Is:

Reverse breakdown voltage is the reverse anode voltage at which the diode conducts a specified amount of reverse current.  Since it's the reverse current across a junction, IR exhibits a knee shaped rise, increasing rapidly once breakdown occurs.

On the curve tracer, the Collector Supply drives the anode.

What The Display Shows:

The display shows VR on the horizontal axis, and the resulting IR on the vertical axis.  The specification is met when at the specified IR, VR is less than or equal to the specified maximum.

How To Do It:

1. Set controls:

A: Max Peak Volts to the lowest setting above the specified VR

B: Max Peak Power Watts to the lowest setting that satisfies (IR x VR)

C: Horizontal Volts/Div to display VR between the 5th and 10th horizontal divisions

D: Vertical Current/Div to display IR between the 5th and 10th vertical divisions

E: Collector Supply Polarity to -DC

F: Configuration to (Base/Open, Emitter/Common)

G: Variable Collector Supply to minimum % (full ccw)

H: DotCursor ON

2. Apply power to the diode:

A: Position the Left/Right switch as appropriate

B: Slowly increase the Variable Collector Supply % until the specified IR is attained

3. Compare to data sheet specifications:

Check that at the specified IR, VR is less than or equal to the specified maximum