TK71750SCL Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The TK71750SCL is a linear voltage regulator IC manufactured by Asahi Kasei Microdevices (AKM) designed to provide a fixed 5V output at 200mA in a surface-mount SOT-23-5 package. This device is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and production continuity. The part delivers positive fixed output regulation with integrated protection features including over-current, over-temperature, and reverse polarity protection, operating across the industrial temperature range of -40°C to 85°C.

Substiute Parts

TK71750SCL

Asahi Kasei Microdevices/AKMIn Stock: 9623TK71750SCL Datasheet

Current PartRFQ

LDK220M50R

STMicroelectronicsIn Stock: 24614LDK220M50R Datasheet

DirectRFQ

LP2985-50DBVR

Texas InstrumentsIn Stock: 32205LP2985-50DBVR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TK71750SCL is determined by the following critical parameters:

Primary Compatibility Criteria:

• Output voltage: 5V fixed
• Package type: SOT-23-5 (SC-74A, SOT-753)
• Output configuration: Positive
• Mounting type: Surface Mount
• Control features: Enable capability

Secondary Compatibility Criteria:

• Output current rating: minimum 150mA (TK71750SCL rated at 200mA)
• Input voltage tolerance: minimum 14V maximum rating
• Protection features: Over-current and over-temperature protection
• Operating temperature range: minimum -40°C to 85°C coverage

Two substitute parts meet these criteria with varying degrees of parameter alignment. The LDK220M50R from STMicroelectronics provides the closest electrical match with 200mA output current capability. The LP2985-50DBVR from Texas Instruments offers a lower output current rating of 150mA but maintains functional compatibility for applications not requiring the full 200mA specification.

Parameter Comparison

Engineering Selection Recommendations

LDK220M50R (STMicroelectronics) - Primary Substitute

The LDK220M50R is the preferred direct replacement for the TK71750SCL. This part maintains identical output current specification (200mA) and package configuration. The device is currently in active production status with ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1), providing superior long-term availability and supply chain stability compared to the obsolete original part. The maximum input voltage specification of 13.2V is marginally lower than the original 14V rating; circuit designs operating near the upper input voltage limit require verification. The dropout voltage of 0.35V at 200mA and extended operating temperature range to 125°C represent improvements over the original specification.

LP2985-50DBVR (Texas Instruments) - Secondary Substitute

The LP2985-50DBVR serves as a functional alternative for applications where the full 200mA output current is not required. This part offers the highest maximum input voltage rating (16V) and includes short-circuit protection in addition to standard over-current and over-temperature protection. The 150mA output current rating necessitates load current verification before implementation. Active production status and ROHS3 compliance ensure supply availability. The higher dropout voltage of 0.58V at rated current should be evaluated in power budget calculations.

Both substitute parts are actively manufactured, ROHS3 compliant, and available in high inventory quantities, providing reliable alternatives to the obsolete TK71750SCL.

Frequently Asked Questions (FAQ)

Q: Can the LDK220M50R directly replace the TK71750SCL without circuit modifications?

A: The LDK220M50R is pin-compatible and functionally equivalent for most applications. The primary consideration is the maximum input voltage specification of 13.2V versus the original 14V. Circuits designed to operate at or near 14V input require verification that the lower specification does not impact system performance.

Q: What is the key difference between the LDK220M50R and LP2985-50DBVR substitutes?

A: The primary difference is output current capability. The LDK220M50R maintains the original 200mA specification, while the LP2985-50DBVR is rated for 150mA. The LP2985-50DBVR offers higher maximum input voltage (16V) and includes short-circuit protection. Selection depends on actual load current requirements.

Q: Are both substitute parts available in the same SOT-23-5 package?

A: Yes. Both the LDK220M50R and LP2985-50DBVR are supplied in SOT-23-5 (SC-74A, SOT-753) packages, ensuring mechanical and electrical pin compatibility with the original TK71750SCL.

Q: What compliance certifications apply to the substitute parts?

A: Both substitute parts carry ROHS3 compliance and REACH Unaffected status. The LDK220M50R has MSL 1 (unlimited moisture sensitivity), while the LP2985-50DBVR also carries MSL 1 rating, both superior to the original part's MSL 3 specification.

Q: Can the LP2985-50DBVR be used in applications requiring 200mA output?

A: The LP2985-50DBVR is rated for 150mA maximum output current. Use in applications requiring sustained 200mA output exceeds the device specification and is not recommended. The LDK220M50R is the appropriate choice for full 200mA load requirements.

Q: What is the operating temperature range difference between the original and substitute parts?

A: The TK71750SCL operates from -40°C to 85°C. Both substitute parts extend the upper temperature limit to 125°C, providing improved thermal margin for industrial applications. The lower temperature limit remains -40°C across all three parts.