Datasheet

TL1963A-xx
SLVS719F –JUNE 2008–REVISED MAY 2011 www.ti.com
ORDERING INFORMATION
(1)
V
OUT
T
A
PACKAGE
(2)
ORDERABLE PART NUMBER TOP-SIDE MARKING
(TYP)
TO-263 – KTT Reel of 500 TL1963A-15KTTR TL1963A-15
1.5 V SOT-223 – DCQ Reel of 2500 TL1963A-15DCQR 1963A-15
SOT-223 – DCY Reel of 2500 TL1963A-15DCYR TF
TO-263 – KTT Reel of 500 TL1963A-18KTTR TL1963A-18
1.8 V SOT-223 – DCQ Reel of 2500 TL1963A-18DCQR 1963A-18
SOT-223 – DCY Reel of 2500 TL1963A-18DCYR TG
TO-263 – KTT Reel of 500 TL1963A-25KTTR TL1963A-25
–40°C to 125°C
2.5 V SOT-223 – DCQ Reel of 2500 TL1963A-25DCQR 1963A-25
SOT-223 – DCY Reel of 2500 TL1963A-25DCYR TH
TO-263 – KTT Reel of 500 TL1963A-33KTTR TL1963A-33
3.3 V SOT-223 – DCQ Reel of 2500 TL1963A-33DCQR 1963A-33
SOT-223 – DCY Reel of 2500 TL1963A-33DCYR TJ
TO-263 – KTT Reel of 500 TL1963AKTTR TL1963A
ADJ
SOT-223 – DCQ Reel of 2500 TL1963ADCQR TL1963A
(1) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
(2) Package drawings, thermal data, and symbolization are available at www.ti.com/packaging.
Table 1. TERMINAL FUNCTIONS
NO.
NAME DESCRIPTION
DCQ DCY KTT
Shutdown. The SHDN pin is used to put the TL1963A-xx 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 with a pullup resistor. The pullup resistor is required to supply
SHDN 1 — 1
the pullup current of the open-collector gate, normally several microamperes, and the SHDN pin
current, typically 3 μA. If unused, the SHDN pin must be connected to V
IN
. The device is in the
low-power shutdown state if the SHDN pin is not connected.
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 μF to
IN 2 1 2 10 μF is sufficient. The TL1963A-xx regulators are designed 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, 6 2, 4 3 Ground
Output. The output supplies power to the load. A minimum output capacitor (ceramic) of 10 μF
OUT 4 3 4 is required to 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
ADJ 5 — 5 internally to ±7 V. It has a bias current of 3 μA 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-xx (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 are caused by the resistance (R
P
) of PC
traces between the regulator and the load. These may be eliminated by connecting the SENSE
SENSE 5 — 5
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 μA 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
Thermal Pad — —
the PCB for rated thermal performance.
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