Date: 06/01/2009

Power-distribution switches provide accurate current limits

Texas Instruments launched four new power-distribution switches TPS2552/3 & TPS2552-1/3-1 versions, which enable end equipment to handle heavy capacitive loads while preventing short-circuits in a variety of applications, such as USB ports/hubs, cell phones, laptops, flat panel TVs and set-top boxes.

The constant current TPS2552/53 devices limit the output current to a safe level by switching into a constant-current mode when the output load exceeds the current-limit threshold while the latch-off TPS2552-1/53-1 turns the switch off completely during over-current events. The accuracy of the TPS2552/53 also enables the device to be used as a simple circuit-breaking or current-limiting solution for a wide range of applications outside of consumer end equipment, including optical modules and low current management rails in telecommunications systems.

Key Features include:

1. +/-6 percent current-limit accuracy at 1.3 A
2. Meets USB current-limiting requirements
3. Adjustable current limit from 75 mA to 1,300 mA
4. Constant current (TPS2552/3) and latch-off (TPS2552-1/3-1) versions
5. Compatible with TPS2550/1
6. Wide, 2.5-V to 6.5-V input range
7. Fast 2-uS over-current response
8. Operating temperature range of -40 degree C to 85 degree C

Key Benefits include:

1. No need to over-design power supply for inaccurate switch
2. Eases USB power implementation
3. Single device used across platforms, with just a resistor change
4. Fault behavior can be optimized for different designs
5. Easy upgrade path from existing TPS2550/1 products
6. Same product allows protection for 2.5-V, 3.3-V and 5-V rails
7. Switch response fast enough to protect power supply
8. Temperature range meets most commercial and industrial requirements

Availability: The TPS2552/53 is available now
Pricing: $0.75 in quantities of 1,000.
Packaging: SOT23-6 and 2mm x 2mm SON-6

For more information visit: www.ti.com
www.power.ti.com