Part Number: LM1084

Function: 5A, Low Dropout Positive Regulator

Package: TO-220, TO-263 Type

Manufacturer: Texas Instruments

Image and Pinouts:

 

Description

The LM1084 is a regulator with a maximum dropout of 1.5 V at 5 A of load current. The device has the same pinout as TI’s industry standard LM317. Two resistors are required to set the output voltage of the adjustable output voltage version of the LM1084. Fixed output voltage versions integrate the adjust resistors. The LM1084 circuit includes a zener trimmed bandgap reference, current limiting, and thermal shutdown. Refer to LM1085 for the 3A version, and the LM1086 for the 1.5A version.

Features

1. Available in 3.3-V, 5.0-V, and Adjustable Versions

2. Current Limiting and Thermal Protection

3. Output Current 5 A

4. Industrial Temperature Range : -40°C to 125°C

5. Line Regulation 0.015% (Typical)

6. Load Regulation 0.1% (Typical)

Applications:

1. Post Regulator for Switching DC-DC Converter

2. High-Efficiency Linear Regulators

3. Battery Chargers

 

Other data sheets are available within the file:

LM1084IS-3.3, LM1084IS-3.3/NOPB, LM1084IS-5.0, LM1084IS-5.0/NOPB

LM1084 Datasheet PDF

Part Number: MAX687

Function: High-Accuracy, Low-Dropout Linear Regulator

Package: DIP, SO 8 Pin Type

Manufacturer: Maxim Integrated

Pinouts:

 

Description

The MAX687 / MAX688 / MAX689 low-dropout linear regulators operate with an input-to-output voltage differential limited only by an external PNP transistor. Outputs are fixed at 3.3V (MAX687/MAX688) or 3.0V (MAX689).

The only external components required are a PNP pass transistor and output, compensation, and bypass capacitors. Base drive to the external transistor is at least 10mA, permitting output currents to exceed 1A when using high-gain transistors (β > 100). Output current limiting is implemented by limiting the external transistor’s base current. Output voltage monitoring and shutdown functions are included.

The 3.3V MAX687 automatically shuts down whenever the output voltage drops below 2.96V. An internal power-fail comparator also monitors the output and provides an early warning of low output voltage before the device shuts down.

When shut down, the output is latched off until the ON input is pulsed. Turning off the power supply in this way prevents battery damage due to excessive discharge or cell-reversal. Typical applications include portable telephones and other battery-powered equipment where the power supply must be disabled when the battery voltage is low.

Features

1. Directly Drives External PNP Transistor

2. 10mA Min Base-Current Drive for >1A Output

3. Power-Fail Output Monitors the Output Voltage

Other data sheets are available within the file:

MAX687CPA, MAX687CSA, MAX687CUA, MAX687EPA, MAX6870ETJ+

 

MAX687 Datasheet PDF Download