lt3092 Linear Technology Corporation, lt3092 Datasheet - Page 4

• Manufacturer Part Number: lt3092
• Description: 200ma Two-terminal Programmable Current Source
• Manufacturer: Linear Technology Corporation

PIN FUNCTIONS
LT3092
IN (Pins 7, 8/Pin 3/Pins 7, 8): Input. This pin supplies
power to bias internal circuitry and supply output load
current. For the device to operate properly and regulate,
the voltage on this pin must be 1.2V to 1.4V above the
OUT pin (depending on output load current—see the
dropout voltage specifi cations in the Electrical Charac-
teristics table).
NC (Pins 3, 5, 6/NA/Pins 1, 6): No Connection. These
pins have no connection to internal circuitry and may be
tied to IN, OUT, GND or fl oated.
OUT (Pins 1, 2/Pin 2/Pins 2, 3, 4): Output. This is the
power output of the device. The LT3092 requires a 0.5mA
minimum load current or the output will not regulate.
BLOCK DIAGRAM
4
(DD/ST/TS8)
SET
10μA
+
–
IN
SET (Pin 4/Pin 1/Pin 5): Set. This pin is the error ampli-
fi er’s noninverting input and also sets the operating bias
point of the circuit. A fi xed 10μA current source fl ows out
of this pin. Two resistors program I
the resistor ratio relative to 10μA. Output current range
is 0.5mA to the maximum rated 200mA level.
Exposed Pad/Tab (Pin 9/Tab/NA): Output. The Exposed
Pad of the DFN package and the Tab of the SOT-223
package are tied internally to OUT. Tie them directly to OUT
pins (Pins 1, 2/Pin 2) at the PCB. The amount of copper
area and planes connected to OUT determine the effective
thermal resistance of the packages.
OUT
3092 BD
OUT
as a function of
3092p