Features: Low Noise: 20VRMS (10Hz to 100kHz)
Low Quiescent Current: 30A/Output
Independent Inputs
Wide Input Voltage Range: 1.8V to 20V
Output Current: 100mA/500mA
Very Low Shutdown Current: <0.1A
Low Dropout Voltage: 300mV/320mV at 100mA/500mA
Adjustable Outputs from 1.22V to 20V
Stable with as Low as 1F/3.3F Output Capacitor
Stable with Aluminum, Tantalum or Ceramic Capacitors
Reverse-Battery Protected
No Protection Diodes Needed
Overcurrent and Overtemperature Protected
Tracking/Sequencing Capability
Thermally Enhanced 16-Lead TSSOP and 16-Lead (5mm * 3mm) DFN PackagesApplication Cellular Phones
Pagers
Battery-Powered Systems
Frequency Synthesizers
Wireless Modems
Tracking/Sequencing Power SuppliesPinout
SpecificationsIN1, IN2 Pin Voltage ......................................... ±20V
OUT1, OUT2 Pin Voltage ................................... ±20V
Input-to-Output Differential Voltage ................ ±20V
ADJ1, ADJ2 Pin Voltage ................................... ... ±7V
BYP1, BYP2 Pin Voltage ................................... ±0.6V
SHDN1, SHDN2 Pin Voltage .............................. ±20V
Output Short-Circut Duration .................... Indefinite
Operating Junction Temperature Range
(Note 2) ............................................ 40 to 125
Storage Temperature Range
FE Package ....................................... 65 to 150
DHC Package .................................... 65 to 125
Lead Temperature (Soldering, 10 sec)............. 300
DescriptionThe LT®3028 is a dual, micropower, low noise, low dropout regulator with independent inputs. With an external 0.01F bypass capacitor, output noise is a low 20VRMS over a 10Hz to 100kHz bandwidth. Designed for use in battery-powered systems, the low 30A quiescent current per output makes it an ideal choice. In shutdown, quiescent current drops to less than 0.1A. Shutdown control is independent for each output, allowing for flexibility in power management. The device is capable of operating over an input voltage range of 1.8V to 20V. Output 1 can supply 500mA of output current with a dropout voltage of 320mV. The device can supply 100mA of output current from Output 2 with a dropout voltage of 300mV. Quiescent current is well controlled in dropout.
The LT3028 regulator is stable with output capacitors as low as 1F for the 100mA output and 3.3F for the 500mA output. Small ceramic capacitors can be used without the series resistance required by other regulators.
Internal protection circuitry includes reverse-battery protection, current limiting and thermal limiting protection. The device is available as an adjustable device with a 1.22V reference voltage. The LT3028 regulator is available in the thermally enhanced 16-lead TSSOP and 16-lead, low profile (5mm * 3mm * 0.75mm) DFN packages.
LT3028 Data Sheet
