LT3050_10 Datasheet, PDF (1/26 Pages) Linear Technology – 100mA, Linear Regulator with Precision Current Limit and Diagnostic Outputs

FEATURES
n _{Output Current Monitor: 1/100}^th _{of IOUT}
n _{Fault Indicator: Current Limit, Minimum IOUT or}
Thermal Limit
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 _{Low Noise: 30μVRMS (10Hz to 100kHz)}
n _{Adjustable Output (VREF = VOUT(MIN) = 0.6V)}
n _{Fixed Output Voltages: 3.3V, 5V}
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}
LT3050 Series
100mA, Linear Regulator
with Precision Current Limit
and Diagnostic Outputs
DESCRIPTION
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
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 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.
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
12V
SHDN
V_IN
1μF 120k
FAULT
10nF
LT3050-5
I_MAX
1.15k
(THRESHOLD = 100mA)
I_MON
0.1μF
11.3k
(THRESHOLD = 10mA)
I_MIN
REF/BYP
GND
5V
2.2μF
3k
(ADC FULL SCALE = 3V)
TO μP ADC
0.1μF
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
3050fa
1