Is there a pin-compatible replacement for LR7805D?

Several parts like CJ78D05 and NCP1117DT50RKG come in the same DPAK/TO-252 package and are likely pin-compatible. However, none are confirmed as direct drop-in replacements without reviewing electrical differences, such as the lower input voltage on the NCP1117.

What risks should I check before replacing LR7805D?

The main risks are electrical and mechanical. First, ensure the substitute's maximum input voltage is at least 35V. Many similar-looking parts are rated for only 15-20V. Second, confirm the package and pinout are identical, as even parts in a DPAK package can have different pin assignments.

LR7805D Alternatives, Datasheet & Cross Reference | LRC

Find and compare replacements for the LR7805D, a 5V 1A linear voltage regulator in a DPAK package. This guide analyzes alternatives, highlighting critical differences in input voltage, package, and temperature range to ensure a reliable substitution.

AI replacement insight

Electrical riskhigh

Many alternatives have a lower max input voltage (Vin), which can lead to device failure if not verified.

Package riskmedium

While many parts use a DPAK/TO-252 package, pinouts for different families (e.g., 78xx vs 1117) can vary.

Sourcing risklow

5V/1A LDOs are a common component class with many manufacturers, offering good availability.

Can it be replaced directly?

No verified direct drop-in replacement has been identified. CJ78D05 is the strongest candidate but requires engineering review of its package and temperature specs. Other candidates in the same package have lower voltage ratings.

Best replacement path

CJ78D05 is the most promising alternative, offering identical key electrical ratings in a likely compatible package, but its lower temperature rating (125°C vs 150°C) must be acceptable for the application.

Main risk

The primary risk when substituting LR7805D is selecting a part with a lower maximum input voltage, as many common alternatives are rated for only 15-20V, not 35V.

Recommended alternatives

Strong electrical match in a likely compatible package, but has a lower maximum operating temperature.

View details

Alternative comparison matrix

Feature / factor	LR7805D	CJ78D05	NCP1117DT50RKG	Compatibility / risk
Package	DPAK (TO-252)	TO-252-2L	DPAK (TO-252)	TO-252-2L / DPAK (TO-252) — Likely same as DPAK (TO-252), but requires verification.; NCP1117DT50RKG: Package is a form-fit match.
Voltage	35.0 V	35.0 V	20.0 V	35.0 V / 20.0 V — Max input voltage matches.; NCP1117DT50RKG: Max input voltage is significantly lower.
Current	1.0 A	1.0 A	1.0 A	1.0 A — Output current matches.; NCP1117DT50RKG: Output current matches.
Temperature	0°C to +150°C	-25°C to +125°C	0°C to +125°C	-25°C to +125°C / 0°C to +125°C — Operating range is narrower on the high end.; NCP1117DT50RKG: Operating range is narrower on the high end.

Application & sourcing insights

Questions & answers

The best alternative appears to be CJ78D05, as it matches the 5V output, 1A current, and 35V maximum input voltage. However, you must verify its TO-252-2L package is compatible with your DPAK footprint and that its 125°C max temperature is sufficient.