AP1117T33L-U Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The AP1117T33L-U is a linear voltage regulator IC manufactured by Diodes Incorporated, designed to provide a fixed 3.3V output at 1A maximum current in a TO-220-3 package. This device is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production requirements. The AP1117T33L-U serves as a positive fixed output regulator suitable for power management applications requiring stable 3.3V regulation with integrated over-current and over-temperature protection.

Key Parameters

Parameter	Value
Manufacturer Part Number	AP1117T33L-U
Manufacturer	Diodes Incorporated
Category	Power Management (PMIC)
Output Voltage (Fixed)	3.3V
Output Current	1A
Input Voltage (Max)	18V
Voltage Dropout (Max)	1.4V @ 1A
Quiescent Current	10 mA
PSRR	60dB (180Hz)
Protection Features	Over Current, Over Temperature
Operating Temperature	0°C ~ 125°C
Package / Case	TO-220-3
Mounting Type	Through Hole
Product Status	Obsolete
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution of the AP1117T33L-U is determined by the following critical parameters:

Output voltage fixed at 3.3V
TO-220-3 package compatibility
Positive output configuration
Over-current and over-temperature protection
Through-hole mounting type
ROHS3 compliance

Substitute parts must maintain the same output voltage, package form factor, and protection features. Variations in maximum input voltage, dropout voltage, output current rating, and quiescent current are acceptable provided the substitute meets or exceeds the application requirements. All identified substitutes are pin-compatible and functionally equivalent for standard 3.3V regulation applications.

Parameter Comparison

Parameter	AP1117T33L-U	LD1117AV33	LD1117V33	LD1117V33C	LM1117T-3.3/NOPB
Manufacturer	Diodes Incorporated	STMicroelectronics	STMicroelectronics	STMicroelectronics	Texas Instruments
Output Voltage	3.3V	3.3V	3.3V	3.3V	3.3V
Output Current	1A	1A	800mA	800mA	800mA
Input Voltage (Max)	18V	15V	15V	15V	15V
Voltage Dropout (Max)	1.4V @ 1A	1.3V @ 1A	1.2V @ 800mA	1.3V @ 800mA	1.2V @ 800mA
Quiescent Current	10 mA	10 mA	10 mA	10 mA	5 mA
PSRR	60dB (180Hz)	75dB (120Hz)	75dB (120Hz)	75dB (120Hz)	75dB (120Hz)
Operating Temperature	0°C ~ 125°C	0°C ~ 125°C	0°C ~ 125°C	-40°C ~ 125°C	0°C ~ 125°C
Package / Case	TO-220-3	TO-220-3	TO-220-3	TO-220-3	TO-220-3
Product Status	Obsolete	Obsolete	Active	Active	Active
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant

Engineering Selection Recommendations

For applications currently using the AP1117T33L-U, the following selection criteria apply:

LD1117AV33 provides the closest electrical match with 1A output current capability and maintains the same quiescent current specification. This part is manufactured by STMicroelectronics and remains functionally equivalent, though classified as obsolete.

LD1117V33 and LD1117V33C are active production alternatives from STMicroelectronics with reduced output current (800mA) and improved PSRR performance. LD1117V33C extends the operating temperature range to -40°C ~ 125°C, suitable for industrial applications. Both parts feature lower dropout voltage at their rated current.

LM1117T-3.3/NOPB is an active production part from Texas Instruments offering the lowest quiescent current (5 mA) and equivalent dropout voltage performance at 800mA output. This part is recommended for new designs prioritizing low standby power consumption.

All substitute parts maintain ROHS3 compliance and TO-220-3 package compatibility. Selection should be based on output current requirements, input voltage constraints, and production status needs.

Frequently Asked Questions (FAQ)

Q: Can LD1117V33 or LD1117V33C replace the AP1117T33L-U in applications requiring 1A output?

A: LD1117V33 and LD1117V33C are rated for 800mA maximum output current, not 1A. These parts are suitable only for applications where the load current does not exceed 800mA. For applications requiring the full 1A capability, LD1117AV33 is the appropriate substitute.

Q: What is the difference between LD1117V33 and LD1117V33C?

A: Both parts are functionally identical with 800mA output current and identical electrical specifications. The primary difference is operating temperature range: LD1117V33 operates from 0°C to 125°C, while LD1117V33C extends to -40°C to 125°C. LD1117V33C is specified for industrial and extended temperature applications.

Q: Are all substitute parts pin-compatible with the AP1117T33L-U?

A: Yes. All listed substitute parts use the TO-220-3 package with identical pin configuration and are directly pin-compatible. No PCB modifications are required for substitution.

Q: Why does the AP1117T33L-U have a higher maximum input voltage (18V) than the substitutes (15V)?

A: The AP1117T33L-U is specified for 18V maximum input, while LD1117 and LM1117 series parts are specified for 15V maximum input. Applications operating above 15V input voltage require the AP1117T33L-U or equivalent parts with higher voltage ratings.

Q: Which substitute part has the best power efficiency?

A: LM1117T-3.3/NOPB offers the lowest quiescent current at 5 mA compared to 10 mA for other parts, resulting in reduced standby power consumption. For applications with continuous operation at rated load, dropout voltage becomes the primary efficiency factor, where LM1117T-3.3/NOPB and LD1117V33 both specify 1.2V @ 800mA.

Q: Are all substitute parts currently in production?

A: LD1117AV33 is obsolete. LD1117V33, LD1117V33C, and LM1117T-3.3/NOPB are active production parts with established supply availability. For new designs, active production parts are recommended.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message