LTC3108 Datasheet, PDF (1/20 Pages) Linear Technology – Ultralow Voltage Step-Up Converter and Power Manager

Electrical Specifications Subject to Change
LTC3108
Ultralow Voltage Step-Up
Converter and Power Manager
FEATURES
n _{Operates from Inputs of 20mV}
n _{Complete Energy Harvesting Power}
Management System
- Selectable V_OUT of 2.35V, 3.3V, 4.1V or 5V
- LDO: 2.2V at 3mA
- Logic Controlled Output
- Reserve Energy Output
n _{Power Good Indicator}
n _{Ultralow IQ: 6μA}
n _{Uses Compact Step-Up Transformers}
n _{Small 12-Lead (4mm × 3mm) DFN or 16-Lead}
SSOP Packages
APPLICATIONS
n _{Remote Sensors and Radio Power}
n _{Surplus Heat Energy Harvesting}
n _HVAC
n _{Industrial Wireless Sensing}
n _{Automatic Metering}
n _{Building Automation}
n _{Indoor Light Energy Harvesting}
DESCRIPTION
The LTC^®3108 is a highly integrated DC/DC converter ideal
for harvesting and managing surplus energy from extremely
low input voltage sources such as TEG (thermoelectric
generators), thermopiles and small solar cells. The step-up
topology operates from input voltages as low as 20mV.
Using a small step-up transformer, the LTC3108 provides a
complete power management solution for wireless sensing
and data acquisition. The 2.2V LDO powers an external
microprocessor, while the main output is programmed to
one of four fixed voltages to power a wireless transmitter
or sensors. The power good indicator signals that the main
output voltage is within regulation. A second output can be
enabled by the host. A storage capacitor provides power
when the input voltage source is unavailable. Extremely
low quiescent current and high efficiency design ensure
the fastest possible charge times of the output reservoir
capacitor.
The LTC3108 is available in a small, thermally enhanced
12-lead (4mm × 3mm) DFN package and a 16-lead SSOP
package.
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
+₊
TEG
20mV TO 500mV
Wireless Remote Sensor Application
Powered From a Peltier Cell
1:100
220μF
1nF
C1
5V
VSTORE
+ _0.1F
330pF
LTC3108
6.3V
C2
V_OUT2
PGD ^PGOOD
SW
VLDO ^2.2V
μP
2.2μF _SENSORS
VS2
V_OUT
3.3V
+
470μF
RF LINK
VS1
V_{OUT2_EN}
VAUX GND
3108 TA01a
1μF
V_OUT Charge Time
1000
V_OUT = 3.3V
C_OUT = 470μF
100
10
1
1:100 Ratio
1:50 Ratio
1:20 Ratio
0
0 50 100 150 200 250 300 350 400
V_IN (mV)
3108 TA01b
3108p
1