TL1963A-Q1

SLVSA79 – APRIL 2010

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TERMINAL FUNCTIONS

NO.

NAME

DESCRIPTION

KTT

Shutdown. The SHDN pin is used to put the TL1963A regulators into a low-power shutdown state. The output

is off when the SHDN pin is pulled low. The SHDN pin can be driven either by 5-V logic or open-collector logic

SHDN

1

with a pullup resistor. The pullup resistor is required to supply the pullup current of the open-collector gate,

normally several microamperes, and the SHDN pin current, typically 3 mA. If unused, the SHDN pin must be

Input. Power is supplied to the device through the IN pin. A bypass capacitor is required on this pin if the

device is more than six inches away from the main input filter capacitor. In general, the output impedance of a

battery rises with frequency, so it is advisable to include a bypass capacitor in battery-powered circuits. A

bypass capacitor (ceramic) in the range of 1 mF to 10 mF is sufficient. The TL1963A regulators are designed

IN

2

to withstand reverse voltages on the IN pin with respect to ground and the OUT pin. In the case of a reverse

input, which can happen if a battery is plugged in backwards, the device acts as if there is a diode in series

with its input. There is no reverse current flow into the regulator, and no reverse voltage appears at the load.

The device protects both itself and the load.

GND

3

Ground

Output. The output supplies power to the load. A minimum output capacitor (ceramic) of 10 mF is required to

OUT

4

prevent oscillations. Larger output capacitors are required for applications with large transient loads to limit

peak voltage transients.

Adjust. For the adjustable TL1963A, this is the input to the error amplifier. This pin is clamped internally to ±7

ADJ

5

V. It has a bias current of 3 mA that flows into the pin. The ADJ pin voltage is 1.21 V referenced to ground,

and the output voltage range is 1.21 V to 20 V.

Sense. For fixed voltage versions of the TL1963A (TL1963A-1.5, TL1963A-1.8, TL1963A-2.5, and

TL1963A-3.3), the SENSE pin is the input to the error amplifier. Optimum regulation is obtained at the point

where the SENSE pin is connected to the OUT pin of the regulator. In critical applications, small voltage drops

SENSE

5

by connecting the SENSE pin to the output at the load as shown in Figure 32. Note that the voltage drop

across the external PC traces adds to the dropout voltage of the regulator. The SENSE pin bias current is 600

mA at the rated output voltage. The SENSE pin can be pulled below ground (as in a dual supply system in

which the regulator load is returned to a negative supply) and still allow the device to start and operate.

For the KTT package, the exposed thermal pad is connected to ground and must be soldered to the PCB for

Thermal Pad

rated thermal performance.

ABSOLUTE MAXIMUM RATINGS

(1)

over operating free-air temperature range (unless otherwise noted)

IN

–20 V to 20 V

OUT

–20 V to 20 V

–20 V to 20 V

Input voltage range

SENSE

–20 V to 20 V

ADJ

–7 V to 7 V

SHDN

–20 V to 20 V

Output short-circuit duration

Indefinite

Operating virtual-junction temperature range

–40°C to 125°C

Storage temperature range

–65°C to 150°C

(1)

Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings

only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating

conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(2)

Absolute maximum input-to-output differential voltage cannot be achieved with all combinations of rated IN pin and OUT pin voltages.

With the IN pin at 20 V, the OUT pin may not be pulled below 0 V. The total measured voltage from IN to OUT cannot exceed ±20 V.

PACKAGE THERMAL DATA

(1)

PACKAGE

BOARD

(2)

TO-263 (KTT)

High K, JESD 51-5

26.5°C/W

24.1°C/W

0.38°C/W

(1)

(2)

between the die junction and the bottom of the exposed pad.

2

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