Datasheet LT3028 (Analog Devices)

LT3028 Dual 100mA/500mA Low Dropout, Low Noise, Micropower Regulators with Independent Inputs
U FEATURES DESCRIPTIO
■
Low Noise: 20
µ
VRMS (10Hz to 100kHz)
The LT®3028 is a dual, micropower, low noise, low drop- ■
Low Quiescent Current: 30
µ
A/Output
out regulator with independent inputs. With an external ■
Independent Inputs
0.01µF bypass capacitor, output noise is a low 20µVRMS ■
Wide Input Voltage Range: 1.8V to 20V
over a 10Hz to 100kHz bandwidth. Designed for use in ■
Output Current: 100mA/500mA
battery-powered systems, the low 30µA quiescent current ■
Very Low Shutdown Current: <0.1
µ
A
per output makes it an ideal choice. In shutdown, quies- ■
Low Dropout Voltage: 300mV/320mV at
cent current drops to less than 0.1µA. Shutdown control
100mA/500mA
is independent for each output, allowing for flexibility in ■ Adjustable Outputs from 1.22V to 20V power management. The device is capable of operating ■ Stable with as Low as 1µF/3.3µF Output Capacitor over an input voltage range of 1.8V to 20V. Output 1 can ■ Stable with Aluminum, Tantalum or supply 500mA of output current with a dropout voltage of Ceramic Capacitors 320mV. The device can supply 100mA of output current ■ Reverse-Battery Protected from Output 2 with a dropout voltage of 300mV. Quiescent ■ No Protection Diodes Needed current is well controlled in dropout. ■ Overcurrent and Overtemperature Protected The LT3028 regulator is stable with output capacitors as ■ Tracking/Sequencing Capability low as 1µF for the 100mA output and 3.3µF for the 500mA ■ Thermally Enhanced 16-Lead TSSOP and 16-Lead output. Small ceramic capacitors can be used without the (5mm × 3mm) DFN Packages series resistance required by other regulators.
U
Internal protection circuitry includes reverse-battery pro-
APPLICATIO S
tection, current limiting and thermal limiting protection. ■ Cellular Phones The device is available as an adjustable device with a 1.22V ■ Pagers reference voltage. The LT3028 regulator is available in the ■ Battery-Powered Systems thermally enhanced 16-lead TSSOP and 16-lead, low ■ Frequency Synthesizers profile (5mm × 3mm × 0.75mm) DFN packages. ■ Wireless Modems , LTC and LT are registered trademarks of Linear Technology Corporation. ■ Tracking/Sequencing Power Supplies Protected by U.S. Patents including 6118263, 6144250.
U TYPICAL APPLICATIO 10Hz to 100kHz Output Noise 3.3V/2.5V Low Noise Regulators
3.3V AT 500mA OUT1 IN1 20 V µVRMS NOISE IN1 0.01µF 10µF 3.7V TO 1µF SHDN1 422k 20V BYP1 ADJ1 VOUT 20 249k 100 µV µV/DIV RMS LT3028 2.5V AT 100mA OUT2 20 IN2 µVRMS NOISE VIN2 0.01µF 10µF 261k 2.9V TO 1µF SHDN2 BYP2 20V ADJ2 3028 TA01b GND 249k 3028 TA01a 3028f 1