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Five output regulator supports TFT-LCD panel applications

Linear Technology Corp has released a five output monolithic switching regulator packaged in a 5mm x 7mm QFN package.

The LT3513 offers a 2.2A (ISW) buck regulator, a 1.5A (ISW) boost regulator, a 250mA (ISW) boost regulator, a 250mA (ISW) inverter and an LDO controller, all in a single package.

Each channel has an independent soft-start/run pin. The LT3513's input voltage range of 4.5V to 30V makes it ideal for a wide array of TFT-LCD applications, including automotive, industrial and unregulated wall transformer-based systems. The device's 2MHz switching frequency keeps switching noise out of critical frequency bands, such as AM radio, and ensures tiny externals. Combined with a 5mm x 7mm QFN package, the LT3513 offers a compact TFT-LCD power solution.

The LT3513's buck regulator can deliver up to 1.2A of output current for logic rails. A lower voltage secondary logic supply may be generated via the LDO controller and an external NPN MOSFET. A high power step-up converter (ISW=1.5A), a lower power step-up converter (ISW=250mA) and an inverting converter (ISW=250mA) provide the three independent output voltages: AVDD, VON and VOFF required by LCD panels.

An integrated high side PNP provides a delayed turn on of the VON signal while Panel Protect circuitry disables VON if any of the four outputs are more than 10 percent below their programmed voltage, protecting the TFT-LCD panel. Other features include integrated schottky diodes, PGOOD pin for AVDD output disconnect and inductor current sense for the buck regulator.

Availability and pricing

The LT3513EUHF is available from stock in a 38-lead 5mm x 7mm QFN package. Pricing starts at $4.25 each in 1,000-piece quantities. An industrial grade version, the LT3513IUHF, is tested and guaranteed to operate from a -40 degrees C to 125 degrees C operating junction temperature and is priced at $5.00 each in 1,000-piece quantities. All versions are available from stock.

Summary of Features: LT3513

4.5V to 30V Input Voltage Range

Four Integrated Switches: 2.2A Buck, 1.5A Boost, 0.25A Boost, 0.25A Inverter (Guaranteed Minimum Current Limit)

External NPN LDO Driver

Fixed Frequency, Low Noise Outputs

Inductor Current Sense for Buck

Soft-Start for All Outputs

Externally Programmable VON Delay

Three Integrated Schottky Diodes

PGOOD Pin for AVDD Output Disconnect

PanelProtect Circuitry Disables VON upon Fault

Thermally Enhanced 38-Lead 5mm – 7mm QFN Package

For more information, visit www.linear.com

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