LP8345CDT-1.8/NOPB Equivalent & Substitute Parts

Part Overview

The LP8345CDT-1.8/NOPB is a linear voltage regulator IC from Texas Instruments designed for positive fixed 1.8V output at 500mA in a TO-252-3 (DPAK) surface mount package. This part is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and procurement continuity. The device provides over current and over temperature protection suitable for low-voltage power management applications.

Substiute Parts

LP8345CDT-1.8/NOPB

Texas InstrumentsIn Stock: 1084LP8345CDT-1.8/NOPB Datasheet

Current PartRFQ

MCP1825S-1802E/EB

Microchip TechnologyIn Stock: 1580MCP1825S-1802E/EB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LP8345CDT-1.8/NOPB is determined by the following critical parameters:

• Fixed output voltage of 1.8V
• Output current capability of 500mA minimum
• Surface mount packaging compatible with TO-252-3 footprint or equivalent thermal performance
• Positive output configuration
• Single regulator output
• RoHS3 compliance for regulatory alignment
• Operating temperature range support (minimum 0°C to 125°C)

The MCP1825S-1802E/EB from Microchip Technology meets these substitution criteria with matching output voltage and current specifications, active product status, and equivalent surface mount packaging in DDPAK-3 format.

Parameter Comparison

Engineering Selection Recommendations

The MCP1825S-1802E/EB is the designated substitute for the obsolete LP8345CDT-1.8/NOPB based on functional equivalence in output voltage and current specifications. Both devices are ROHS3 compliant and provide the required 1.8V fixed output at 500mA for surface mount applications.

Key considerations for selection:

The MCP1825S-1802E/EB has an active product status, ensuring long-term availability and supply chain continuity compared to the obsolete LP8345CDT-1.8/NOPB. The substitute device operates across an extended temperature range (-40°C to 125°C) versus the original part's 0°C to 125°C range, providing broader environmental compatibility.

The MCP1825S-1802E/EB features additional protection mechanisms including short circuit protection and under voltage lockout (UVLO) beyond the over current and over temperature protection of the original device. The substitute has a specified dropout voltage of 0.35V at 500mA, whereas the original part does not provide this specification.

Package footprints differ between the TO-252-3 (DPAK) original and the TO-263-4 (D2PAK/DDPAK-3) substitute. PCB layout modifications are required to accommodate the different pin configuration and thermal tab placement. Both packages provide equivalent thermal performance for the specified 500mA output current.

Frequently Asked Questions (FAQ)

Q: Can the MCP1825S-1802E/EB directly replace the LP8345CDT-1.8/NOPB without PCB modifications?

A: No. While both devices are functionally equivalent in output voltage and current, the package types differ. The LP8345CDT-1.8/NOPB uses TO-252-3 (DPAK) packaging, while the MCP1825S-1802E/EB uses TO-263-4 (D2PAK/DDPAK-3) packaging. PCB layout changes are required to accommodate the different pin arrangement and thermal tab location.

Q: What are the key electrical differences between these two parts?

A: Both devices provide 1.8V fixed output at 500mA. The MCP1825S-1802E/EB has a lower maximum input voltage (6V vs 10V), higher quiescent current (220 µA vs 50 µA), and includes additional protection features (short circuit and UVLO). The substitute offers a specified dropout voltage of 0.35V at 500mA.

Q: Is the MCP1825S-1802E/EB suitable for applications requiring the full 10V input range of the original part?

A: No. The MCP1825S-1802E/EB has a maximum input voltage of 6V, which is lower than the LP8345CDT-1.8/NOPB specification of 10V. Applications requiring input voltages above 6V require alternative solutions.

Q: Are both parts RoHS compliant?

A: Yes. Both the LP8345CDT-1.8/NOPB and MCP1825S-1802E/EB are ROHS3 compliant, meeting current regulatory requirements for hazardous substance restrictions.

Q: What is the impact of the higher quiescent current in the MCP1825S-1802E/EB?

A: The MCP1825S-1802E/EB has a quiescent current of 220 µA compared to 50 µA in the original part. In battery-powered or low-power standby applications, this difference may impact overall system power consumption and should be evaluated against application requirements.

Q: Does the extended operating temperature range of the MCP1825S-1802E/EB provide any advantage?

A: Yes. The MCP1825S-1802E/EB operates from -40°C to 125°C, compared to 0°C to 125°C for the original part. This extended lower temperature limit provides compatibility with applications requiring operation in cold environments.