Datasheet

LT3080
8
3080fc
Typical perForMance characTerisTics
Output Voltage Noise
Error Amplifier Gain and Phase
V
CONTROL
(Pin 5/Pin 5/Pin 4/Pin 4/NA): This pin is the
supply pin for the control circuitry of the device. The cur-
rent flow into this pin is about 1.7% of the output current.
For the device to regulate, this voltage must be more than
1.2V to 1.35V greater than the output voltage (see dropout
specifications).
IN (Pins 7, 8/Pins 7, 8/Pin 5/Pin 5/Pin 3): This is the
collector to the power device of the LT3080. The output
load current is supplied through this pin. For the device
to regulate, the voltage at this pin must be more than
0.1V to 0.5V greater than the output voltage (see dropout
specifications).
NC (Pin 6/Pin 6/Pin 1/Pin 1/NA): No Connection. No con-
nect pins have no connection to internal circuitry and may
be tied to V
IN
, V
CONTROL
, V
OUT
, GND or floated.
OUT (Pins 1-3/Pins 1-3/Pin 3/Pin 3/Pin 2): This is the
power output of the device. There must be a minimum
load current of 1mA or the output may not regulate.
SET (Pin 4/Pin 4/Pin 2/Pin 2/Pin 1): This pin is the input
to the error amplifier and the regulation set point for
the device. A fixed current of 10µA flows out of this pin
through a single external resistor, which programs the
output voltage of the device. Output voltage range is zero
to the absolute maximum rated output voltage. Transient
performance can be improved by adding a small capacitor
from the SET pin to ground.
Exposed Pad (Pin 9/Pin 9/NA/NA/NA): OUT on MS8E and
DFN packages.
TAB: OUT on DD-Pak, TO-220 and SOT-223 packages.
pin FuncTions
(DD/MS8E/Q/T/ST)
V
OUT
100µV/DIV
TIME 1ms/DIV
3080 G27
V
OUT
= 1V
R
SET
= 100k
C
SET
= O.1µF
C
OUT
= 10µF
I
LOAD
= 1.1A
FREQUENCY (Hz)
–30
GAIN (dB)
PHASE (DEGREES)
–10
20
10k 100k10010 1k 1M
3080 G28
–20
0
10
–15
15
–25
–5
5
–200
0
300
–100
100
200
–50
250
–150
50
150
I
L
= 1.1A
I
L
= 100mA
I
L
= 100mA
I
L
= 1.1A