LT3050 Datasheet, PDF (1/20 Pages) Linear Technology – 100mA, Low Noise Linear Regulator With Precision Current Limit And Diagnostic Functions

LT3050
FEATURES
100mA, Low Noise
Linear Regulator With Precision Current
Limit And Diagnostic Functions
DESCRIPTION
n _{Output Current: 100mA}
n _{Dropout Voltage: 340mV}
n _{Input Voltage Range: 1.6V to 45V}
n _{Programmable Precision Current Limit: ±5%}
n _{Programmable Minimum IOUT Monitor}
n _{Output Current Monitor: 1/100}^th _{of IOUT}
n _{Fault Indicator: Current Limit, Minimum IOUT or}
Thermal Limit
n _{Low Noise: 30μVRMS (10Hz to 100kHz)}
n _{Adjustable Output (VREF = VOUT(MIN) = 0.6V)}
n _{Output Tolerance: ±2% Over Line, Load and Temperature}
n _{Stable with Low ESR, Ceramic Output Capacitors}
(2.2μF minimum)
n _{Shutdown Current: <1μA}
n _{Reverse-Battery, Reverse-Output and}
Reverse-Current Protection
n _{Thermal Limit Protection}
n _{12-Lead 3mm × 2mm DFN and MSOP Packages}
APPLICATIONS
n _{Protected Antenna Supplies}
n _{Automotive Telematics}
n _{Industrial Applications (Trucks, Forklifts, etc.)}
n _{High Reliability Applications}
The LT^®3050 is a micro-power, low noise, low dropout
voltage (LDO) linear regulator. The device supplies 100mA
of output current with a dropout voltage of 340mV. A 10nF
bypass capacitor reduces output noise to 30μV_RMS in a
10Hz to 100kHz bandwidth and soft-starts 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.
A single resistor programs the LT3050’s current limit, accurate
to ±5% over a wide input voltage and temperature range.
A single resistor programs the LT3050’s minimum output
current monitor, useful for detecting open-circuit conditions.
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.
The LT3050 optimizes stability and transient response
with low ESR ceramic capacitors, requiring a minimum
of 2.2μF. The LT3050 is available as an adjustable device
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.
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.
TYPICAL APPLICATION
5V Supply with 100mA Precision Current Limit, 10mA I_MIN
IN
OUT
5V
12V
V_IN
1μF
120k
SHDN
1%
442k
ADJ
FAULT
1%
LT3050
60.4k
2.2μF
I_MAX
10nF ^1.15k
(THRESHOLD = 100mA)
I_MON
3k
(ADC FULL SCALE = 3V)
TO μP ADC
0.1μF
I_MIN
REF/BYP
0.1μF ^11.3k
(THRESHOLD = 10mA)
GND
10nF
3050 TA01
External Current Limit
R_IMAX = 1.15k
105
V_OUT = 5V
104
103
102
V_IN = 15V
101
100
V_IN = 12V
99
98
V_IN = 5.6V
97
96
95
–75 –50 –25
0 –25 50 75 100 125 150 175
TEMPERATURE (°C)
3050 TA01a
3050f
1