# Laser Diode Burn-In Log Worksheet

> Source: https://netray.co/tools/laser-diode-burn-in-log-worksheet
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

Editable burn-in record that computes power degradation percent per unit and flags devices drifting past your limit.

## Category

quality

## Industry

Photonics

## Audience

- Reliability engineer
- Test engineer
- Production supervisor

## Tool

**Kind:** worksheet

**Mode:** editable

**Columns:**

#### Serial number

**Key:** serial

**Type:** text

#### Burn-in station

**Key:** station

**Type:** text

#### Case temp (C)

**Key:** temp

**Type:** number

**Format:** decimal

#### Hours on test

**Key:** hours

**Type:** number

**Format:** integer

#### Initial power (W)

**Key:** p0

**Type:** number

**Format:** decimal

#### Current power (W)

**Key:** p1

**Type:** number

**Format:** decimal

#### Max allowed drop (%)

**Key:** limit

**Type:** number

**Format:** percent

#### Power drop (%)

**Key:** drop

**Type:** number

**Expr:** (p0 - p1) / max(p0, 0.0001) * 100

**Format:** percent

#### Drop per 100 h (%)

**Key:** rate

**Type:** number

**Expr:** (p0 - p1) / max(p0, 0.0001) * 100 / max(hours, 1) * 100

**Format:** decimal

#### Within limit (1=yes)

**Key:** ok

**Type:** number

**Expr:** if(lte((p0 - p1) / max(p0, 0.0001) * 100, limit), 1, 0)

**Format:** integer

**Rows:**

**Serial:** LD-1001

**Station:** BI-A1

**Temp:** 45

**Hours:** 48

**P0:** 5.02

**P1:** 5

**Limit:** 3

**Serial:** LD-1002

**Station:** BI-A2

**Temp:** 45

**Hours:** 48

**P0:** 4.98

**P1:** 4.9

**Limit:** 3

**Serial:** LD-1003

**Station:** BI-A3

**Temp:** 45

**Hours:** 48

**P0:** 5.05

**P1:** 4.78

**Limit:** 3

**Serial:** LD-1004

**Station:** BI-A4

**Temp:** 45

**Hours:** 96

**P0:** 5.1

**P1:** 5.04

**Limit:** 3

**Serial:** LD-1005

**Station:** BI-B1

**Temp:** 60

**Hours:** 96

**P0:** 4.95

**P1:** 4.9

**Limit:** 3

**Totals:**

#### Units within limit

**Key:** ok

**Agg:** sum

**Format:** integer

#### Worst power drop

**Key:** drop

**Agg:** max

**Format:** percent

**Summary:**

#### Burn-in screen yield

**Key:** screen_yield

**Expr:** sum_ok / max(count, 1) * 100

**Format:** percent

**Notes:** Burn-in conditions, duration and acceptance limits come from your product reliability plan. This sheet records and calculates only; it does not predict lifetime.

## Content

**Intro:** Burn-in screens early failures by running devices under stress before shipment. This worksheet records hours and power, then calculates drift per device so out of limit units are easy to find.

**Sections:**

#### How to use the worksheet

**Body:** Log each device with its station, case temperature, hours on test, initial power and current power, along with the allowed drop from your reliability plan. The sheet calculates percent power drop and drop per 100 hours, then marks units within limit. Re-enter the current power at each checkpoint, or add a new row per checkpoint to retain history.

**Bullets:**

- Record temperature and drive conditions
- Use the same meter for initial and later readings
- Log checkpoints as separate rows
- Quarantine units outside the limit

#### The calculation

**Body:** Power drop percent equals initial power minus current power, divided by initial power, times 100. For LD-1003 above, 5.05 W falling to 4.78 W is about 5.3 percent, beyond a 3 percent limit. The drop per 100 hours column normalizes drift across different durations for quick comparison.

#### Interpreting drift

**Body:** Early rapid drift can indicate a defect that burn-in is designed to catch. Slow, stable drift is typical. Look at trends by station and temperature as well, since a failing station or fixture can mimic bad devices. Feed repeated failures into your corrective action process and consider linking lots to results in your ERP.

**Cta:** If burn-in results sit in lab files, Netray can help tie them to lots and serial numbers in your ERP for traceability.

**Faq:**

#### How long should burn-in run?

**Answer:** It depends on the device, application and reliability plan. Durations from tens to hundreds of hours are common. Use your qualification data rather than a general figure.

#### Does this predict lifetime?

**Answer:** No. It records and screens. Lifetime prediction requires dedicated reliability testing and statistical models such as accelerated life tests.

#### Why track the station?

**Answer:** A faulty station, fixture or cooling problem can cause apparent drift across many devices. Station data helps separate device issues from equipment issues.

#### Can I add more checkpoints?

**Answer:** Yes. Add a new row for each checkpoint with the same serial number and updated hours and power. Export to Excel for plotting.

## Search terms

laser diode burn-in log, burn-in test record template, laser power degradation tracking, burn in data sheet excel, diode reliability screening log, led laser burn-in worksheet, photonics reliability test template, power drift log

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