LT3050 Series
100mA, Linear Regulator
with Precision Current Limit
and Diagnostic Outputs
DESCRIPTION
FEATURES
th
The LT®3050 series are micro-power, low noise, low
dropout voltage (LDO) linear regulators. The devices
supply 100mA of output current with a dropout voltage of
340mV. A 10nF bypass capacitor reduces output noise to
n
Output Current Monitor: 1/100 of I
OUT
n
Fault Indicator: Current Limit, Minimum I
or
OUT
Thermal Limit
n
n
n
n
n
n
n
n
n
n
Output Current: 100mA
Dropout Voltage: 340mV
30μV
in a 10Hz to 100kHz bandwidth and soft-starts
RMS
Input Voltage Range: 1.6V to 45V
the reference. The LT3050’s 45V input voltage rating
combined with its precision current limit and diagnostic
functions make the IC an ideal choice for robust, high
reliability applications.
Programmable Precision Current Limit: 5ꢀ
Programmable Minimum I
Monitor
(10Hz to 100kHz)
OUT
Low Noise: 30μV
RMS
Adjustable Output (V = V
= 0.6V)
REF
OUT(MIN)
AsingleresistorprogramstheLT3050’scurrentlimit,accurate
to 5ꢀ over a wide input voltage and temperature range.
A single resistor programs the LT3050’s minimum output
currentmonitor,usefulfordetectingopen-circuitconditions.
The current monitor function sources a current equal to
1/100th of output current. A logic FAULT pin asserts low if
the LT3050 is in current limit, operating below its minimum
output current (open-circuit) or is in thermal shutdown.
Fixed Output Voltages: 3.3V, 5V
Output Tolerance: 2ꢀ Over Line, Load and Temperature
Stable with Low ESR, Ceramic Output Capacitors
(2.2μF minimum)
n
n
Shutdown Current: <1μA
Reverse-Battery, Reverse-Output and
Reverse-Current Protection
Thermal Limit Protection
12-Lead 3mm × 2mm DFN and MSOP Packages
n
n
The LT3050 optimizes stability and transient response
with low ESR ceramic capacitors, requiring a minimum of
2.2μF. The LT3050 is available in fixed output voltages of
3.3V and 5V, and as an adjustable version with an output
voltage range down to the 0.6V reference.The LT3050 is
available in the thermally-enhanced 12-Lead 3mm × 2mm
DFN and MSOP packages.
APPLICATIONS
n
Protected Antenna Supplies
n
Automotive Telematics
n
Industrial Applications (Trucks, Forklifts, etc.)
High Reliability Applications
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
n
TYPICAL APPLICATION
External Current Limit RIMAX = 1.15k
105
5V Supply with 100mA Precision Current Limit, 10mA IMIN
V
OUT
= 5V
104
103
102
101
100
99
IN
OUT
5V
12V
IN
SHDN
2.2ꢁF
V
= 15V
1ꢁF
120k
IN
V
FAULT
V
V
= 12V
LT3050-5
IN
IN
I
MAX
I
TO ꢁP ADC
0.1ꢁF
MON
1.15k
10nF
= 5.6V
98
3k
(THRESHOLD = 100mA)
(ADC FULL SCALE = 3V)
97
I
REF/BYP
96
MIN
11.3k
0.1ꢁF
GND
95
10nF
(THRESHOLD = 10mA)
–75 –50 –25
0
–25 50 75 100 125 150 175
3050 TA01
TEMPERATURE (°C)
3050 TA01a
3050fa
1