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TS30011/12/13

Version 1.6

Specifications subject to change

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Copyright © 2012, Triune Systems, LLC

FUNCTIONAL DESCRIPTION

The TS30011/12/13 current-mode synchronous step-down power supply product is ideal for use in the commercial, industrial,

and automotive market segments. It includes flexibility to be used for a wide range of output voltages and is optimized for high

low cost LC filter combinations. Additionally, the fixed output versions enable a minimum external component count to provide

a complete regulation solution with only 4 external components: an input bypass capacitor, an inductor, an output capacitor,

and the bootstrap capacitor. The regulator automatically transitions between PFM and PWM mode to maximize efficiency for

the load demand.

The TS30011/12/13 was designed to provide these system benefits:



Reduced board real estate



Lower system cost

o

Lower cost inductor

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Low external parts count



Ease of design

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Bill of Materials and suggested board layout provided

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Power Good output

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Integrated compensation network

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Wide input voltage range



Robust solution

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Over current, over voltage and over temperature protection

DETAILED PIN DESCRIPTION

Unregulated input, VCC

This terminal is the unregulated input voltage source for the IC. It is recommended that a 10uF bypass capacitor be placed

close to the device for best performance. Since this is the main supply for the IC, good layout practices need to be followed for

this connection.

Bootstrap control, BST

This terminal will provide the bootstrap voltage required for the upper internal NMOS switch of the buck regulator. An external

ceramic capacitor placed between the BST input terminal and the VSW pin will provide the necessary voltage for the upper

switch. In normal operation the capacitor is re-charged on every low side synchronous switching action. In the case of where

the switch mode approaches 100% duty cycle for the high side FET, the device will automatically reduce the duty cycle switch

Sense feedback, FB

This is the input terminal for the output voltage feedback.

possible, and should be made as close as possible to the capacitor. The trace should not be shared with any other connection.

(Figure 23)

For adjustable mode versions, this should be connected to the external resistor divider. To choose the resistors, use the

following equation:

The input to the FB pin is high impedance, and input current should be less than 100nA. As a result, good layout practices are

required for the feedback resistors and feedback traces. When using the adjustable version, the feedback trace should be kept

as short as possible and minimum width to reduce stray capacitance and to reduce the injection of noise.

For the adjustable version, the ratio of VCC/Vout cannot exceed 16.