LT1963AES8-2.5 Linear Technology, LT1963AES8-2.5 Datasheet - Page 13

• Manufacturer Part Number: LT1963AES8-2.5
• Description: IC LDO REG LONOIS 1.5A 2.5V8SOIC
• Manufacturer: Linear Technology

Specifications of LT1963AES8-2.5

• Regulator Topology: Positive Fixed
• Voltage - Output: 2.5V
• Voltage - Input: Up to 20V
• Voltage - Dropout (typical): 0.34V @ 1.5A
• Number Of Regulators: 1
• Current - Output: 1.5A
• Current - Limit (min): 1.6A
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

PIN FUNCTIONS
OUT: Output. The output supplies power to the load.
A minimum output capacitor of 10µF is required to
prevent oscillations. Larger output capacitors will be
required for applications with large transient loads to limit
peak voltage transients. See the Applications Information
section for more information on output capacitance and
reverse output characteristics.
SENSE: Sense. For fixed voltage versions of the LT1963A
(LT1963A-1.5/LT1963A-1.8/LT1963A-2.5/LT1963A-3.3),
the SENSE pin is the input to the error amplifier. Optimum
regulation will be obtained at the point where the SENSE
pin is connected to the OUT pin of the regulator. In criti-
cal applications, small voltage drops are caused by the
resistance (R
load. These may be eliminated by connecting the SENSE
pin to the output at the load as shown in Figure 1 (Kelvin
Sense Connection). Note that the voltage drop across
the external PC traces will add to the dropout voltage of
the regulator. The SENSE pin bias current is 600µA at
the nominal rated output voltage. The SENSE pin can be
pulled below ground (as in a dual supply system where
the regulator load is returned to a negative supply) and
still allow the device to start and operate.
ADJ: Adjust. For the adjustable LT1963A, this is the input
to the error amplifier. This pin is internally clamped to ± 7V.
It has a bias current of 3µA which flows into the pin. The
ADJ pin voltage is 1.21V referenced to ground and the
output voltage range is 1.21V to 20V.
SHDN: Shutdown. The SHDN pin is used to put the LT1963A
regulators into a low power shutdown state. The output will
P
) of PC traces between the regulator and the
be off when the SHDN pin is pulled low. The SHDN pin can
be driven either by 5V logic or open-collector logic with a
pull-up resistor. The pull-up resistor is required to supply
the pull-up current of the open-collector gate, normally
several microamperes, and the SHDN pin current, typically
3µA. If unused, the SHDN pin must be connected to V
The device will be in the low power shutdown state if the
SHDN pin is not connected.
IN: 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 in
the range of 1µF to 10µF is sufficient. The LT1963A regula-
tors 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 will act as if there is a diode in
series with its input. There will be no reverse current flow
into the regulator and no reverse voltage will appear at
the load. The device will protect both itself and the load.
V
IN
+
Figure 1. Kelvin Sense Connection
IN
SHDN
LT1963A
GND
LT1963A Series
SENSE
OUT
R
R
P
P
+
1963A F01
LOAD
13
1963afe
IN
.