features

135-mW -Maximum (5-V Input) High-Side

MOSFET Switch

250 mA Continuous Current

Short-Circuit and Thermal Protection With

Overcurrent Logic Output

Operating Range . . . 2.7-V to 5.5-V

Logic-Level Enable Input

2.5-ms Typical Rise Time

Undervoltage Lockout

10 mA Maximum Standby Supply Current

Bidirectional Switch

Available in 8-pin SOIC and PDIP Packages

Ambient Temperature Range, –40°C to 85°C

2-kV Human-Body-Model, 200-V

Machine-Model ESD Protection

typical applications

Notebook, Desktop and Palmtop PCs

Monitors, Keyboards, Scanners, and

Printers

Digital Cameras, Phones, and PBXs

Hot-Insertion Applications

description

The TPS2045 and TPS2055 power-distribution switches are intended for applications where heavy capacitive

loads and short circuits are likely. Each of these 135-mW N-channel MOSFET high-side power switches is

controlled by a logic enable compatible with 5-V and 3-V logic. Gate drive is provided by an internal charge pump

that controls the power-switch rise times and fall times to minimize current surges during switching. The charge

pump requires no external components and allows operation from supplies as low as 2.7 V.

When the output load exceeds the current-limit threshold or a short is present, the TPS2045 and TPS2055 limit

the output current to a safe level by switching into a constant-current mode, pulling the overcurrent (OC) logic

output low. When continuous heavy overloads and short circuits increase the power dissipation in the switch,

causing the junction temperature to rise, a thermal protection circuit shuts off the switch in overcurrent to prevent

damage. Recovery from a thermal shutdown is automatic once the device has cooled sufficiently. Internal

circuitry ensures the switch remains off until valid input voltage is present.

The TPS2045 and TPS2055 are designed to limit at 0.44-A load. These power-distribution switches, available

in 8-pin small-outline integrated circuit (SOIC) and 8-pin plastic dual-in-line packages (PDIP), operate over an

ambient temperature range of –40°C to 85°C.