LT1964_15 Datasheet, PDF (1/16 Pages) Linear Technology – 200mA, Low Noise, Low Dropout Negative Micropower Regulator

LT1964
200mA, Low Noise,
Low Dropout Negative
Micropower Regulator
FEATURES
n _{Low Noise: 30μVRMS (10Hz to 100kHz)}
n _{Low Quiescent Current: 30μA}
n _{Low Dropout Voltage: 340mV}
n _{Output Current: 200mA}
n _{Fixed Output Voltage: –5V}
n _{Adjustable Output from –1.22V to – 20V}
n _{Positive or Negative Shutdown Logic}
n _{3μA Quiescent Current in Shutdown}
n _{Stable with 1μF Output Capacitor}
n _{Stable with Aluminum, Tantalum, or Ceramic}
Capacitors
n _{Thermal Limiting}
n _{Low Profile (1mm) ThinSOT™ and (0.75mm) 8-Pin}
3mm × 3mm DFN Packages
APPLICATIONS
n _{Battery-Powered Instruments}
n _{Low Noise Regulator for Noise-Sensitive}
Instrumentation
n _{Negative Complement to LT1761 Family of}
Positive LDOs
TYPICAL APPLICATION
–5V Low Noise Regulator
DESCRIPTION
The LT^®1964 is a micropower low noise, low dropout nega-
tive regulator. The device is capable of supplying 200mA
of output current with a dropout voltage of 340mV. Low
quiescent current (30μA operating and 3μA shutdown)
makes the LT1964 an excellent choice for battery-pow-
ered applications. Quiescent current is well controlled in
dropout.
Other features of the LT1964 include low output noise.
With the addition of an external 0.01μF bypass capacitor,
output noise is reduced to 30μV_RMS over a 10Hz to 100kHz
bandwidth. The LT1964 is capable of operating with small
capacitors and is stable with output capacitors as low
as 1μF. Small ceramic capacitors can be used without
the necessary addition of ESR as is common with other
regulators. Internal protection circuitry includes reverse
output protection, current limiting, and thermal limiting.
The device is available with a fixed output voltage of –5V
and as an adjustable device with a –1.22V reference volt-
age. The LT1964 regulators are available in a low profile
(1mm) ThinSOT and the low profile (0.75mm) 8-pin
(3mm × 3mm) DFN packages.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ThinSOT is
a trademark of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
10Hz to 100kHz Output Noise
V_IN
–5.4V
TO –20V
1μF
GND
SHDN BYP
LT1964-5
IN
OUT
10μF
0.01μF
–5V AT 200mA
30μV_RMS NOISE
1964 TA01a
V_OUT
100μV/DIV
30μV_RMS
1ms/DIV
1964 TA01b
1964fb
1