LP38690, LP38692 1-A Low Dropout CMOS Linear Regulators Stable with Ceramic Output Capacitors
1 Features
- Wide Input Voltage Range (2.7 V to 10 V)
- 2.5% Output Accuracy (25°C)
- Low Dropout Voltage: 450 mV at 1 A
(typical, 5 VOUT) - Precision (Trimmed) Bandgap Reference
- Ensured Specifications for –40°C to 125°C
- 1-µA Off-State Quiescent Current
- Thermal Overload Protection
- Foldback Current Limiting
- 3-Lead TO-252, 5-Lead SOT-223, and 6-Bump WSON Packages
- Enable Pin (LP38692)
- Ground Pin Current: 55 µA (typical) at Full Load
- Precision Output Voltage: 2.5% (25°C) Accuracy
2 Applications
- Hard Disk Drives
- Notebook Computers
- Battery Powered Devices
- Portable Instrumentation
3 Description
The LP38690 and LP38692 low-dropout CMOS linear regulators provide tight output tolerance (2.5% typical), extremely low dropout voltage (450 mV at a 1-A load current, VOUT = 5 V), and excellent AC performance utilizing ultra low ESR ceramic output capacitors.
The low thermal resistance of the WSON, SOT-223, and TO-252 packages allow the full operating current to be used even in high ambient temperature environments.
The use of a PMOS power transistor means that no DC base drive current is required to bias it allowing ground pin current to remain below 100 µA regardless of load current, input voltage, or operating temperature.
Device Information(1)
| PART NUMBER | PACKAGE | BODY SIZE (NOM) |
|---|---|---|
| LP38690 | TO-252 (3) | 6.58 mm x 6.10 mm |
| WSON (6) | 3.00 mm x 3.00 mm | |
| LP38692 | SOT-223 (5) | 6.50 mm x 3.56 mm |
| WSON (6) | 3.00 mm x 3.00 mm |
Simplified Schematic for LP38690
**WSON package devices only.
Simplified Schematic for LP38692
**WSON package devices only.
4 Revision History
Changes from L Revision (March 2015) to M Revision
- Added top navigator icon for TI Designs Go
- Added Caution note to Foldback Current Limiting subsection Go
Changes from K Revision (December 2014) to L Revision
- Changed "mA" back to "mV" - error from SDS conversion.Go
Changes from J Revision (April 2013) to K Revision
- Changed Device Information and ESD Rating tables, Feature Description, Device Functional Modes, Application and Implementation, Power Supply Recommendations, Layout, Device and Documentation Support, and Mechanical, Packaging, and Orderable Information sections; update Thermal Values moved some curves to Application Curves section; change package name PFM to TO-252 (National to TI nomenclature) and pin names from VIN, VOUT to IN, OUT. Go
Changes from I Revision (April 2013) to J Revision
- Changed layout of National Data Sheet to TI formatGo
5 Pin Configuration and Functions
Pin Functions
| PIN | TYPE | DESCRIPTION | ||||
|---|---|---|---|---|---|---|
| NAME | LP38690 | LP38692 | ||||
| TO-252 | WSON | SOT-223 | WSON | |||
| EN | — | — | 1 | 3 | I | The Enable (EN) pin allows the part to be turned ON and OFF by pulling this pin HIGH or LOW. |
| GND | TAB | 2 | 5 | 2 | — | Circuit ground for the regulator. For the TO-252 and SOT-223 packages this is thermally connected to the die and functions as a heat sink when soldered down to a large copper plane. |
| IN | 3 | 1, 6 | 4 | 1, 6 | I | This is the input supply voltage to the regulator. For WSON devices, both IN pins must be tied together for full current operation (500 mA maximum per pin). |
| OUT | 1 | 4 | 3 | 4 | O | Regulated output voltage. |
| SNS | — | 5 | — | 5 | I | WSON only - Output sense pin allows remote sensing at the load which eliminates the error in output voltage due to voltage drops caused by the resistance in the traces between the regulator and the load. This pin must be tied to VOUT. |
| DAP | — | X | — | X | — | WSON only - The DAP (Exposed Pad) functions as a thermal connection when soldered to a copper plane. See WSON Mounting section in Layout for more information. |
