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.
n
n
n
n
Operates from Inputs of 20mV
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
Power Good Indicator
Ultralow I
Q
: 6μA
Uses Compact Step-Up Transformers
Small 12-Lead (4mm
×
3mm) DFN or 16-Lead
SSOP Packages
APPLICATIONS
n
n
n
n
n
n
n
Remote Sensors and Radio Power
Surplus Heat Energy Harvesting
HVAC
Industrial Wireless Sensing
Automatic Metering
Building Automation
Indoor Light Energy Harvesting
TYPICAL APPLICATION
Wireless Remote Sensor Application
Powered From a Peltier Cell
1nF
1:100
+
TEG
C1
330pF
C2
20mV TO 500mV
SW
VSTORE
LTC3108
V
OUT2
PGOOD
PGD
2.2V
VLDO
5V
1000
V
OUT
Charge Time
V
OUT
= 3.3V
C
OUT
= 470μF
+
220μF
+
0.1F
6.3V
100
TIME (sec)
μP
2.2μF SENSORS
10
VS2
V
OUT
3.3V
+
470μF
RF LINK
1
1:100 Ratio
1:50 Ratio
1:20 Ratio
0
50
100 150 200 250 300 350 400
V
IN
(mV)
3108 TA01b
VS1
VAUX
V
OUT2_EN
GND
1μF
3108 TA01a
0
3108p
1
LTC3108
ABSOLUTE MAXIMUM RATINGS
(Note 1)
SW Voltage ..................................................–0.3V to 2V
C1 Voltage....................................................–0.3V to 6V
C2 Voltage.......................................................–8V to 8V
V
OUT2
, V
OUT2_EN
...........................................–0.3V to 6V
VAUX....................................................15mA into VAUX
VS1, VS2, VAUX, V
OUT
, PGD ........................–0.3V to 6V
VLDO, VSTORE ............................................–0.3V to 6V
Operating Temperature (Note 2).............. –40°C to 85°C
Storage Temperature Range.................. –65°C to 125°C
PIN CONFIGURATION
TOP VIEW
GND
VAUX
VSTORE
V
OUT
V
OUT2
VLDO
PGD
1
2
3
4
5
6
13
GND
12
SW
11
C2
10
C1
9
8
7
V
OUT2_EN
VS1
VS2
VAUX
VSTORE
V
OUT
V
OUT2
VLDO
PGD
GND
1
2
3
4
5
6
7
8
TOP VIEW
16 GND
15 SW
14 C2
13 C1
12 V
OUT2_EN
11 VS1
10 VS2
9
GND
DE PACKAGE
12-LEAD (4mm 3mm) PLASTIC DFN
T
JMAX
= 125°C,
θ
JA
= 43°C/W,
θ
JC
= 4.3°C/W
EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB (NOTE 4)
GN PACKAGE
16-LEAD PLASTIC SSOP NARROW
T
JMAX
= 125°C,
θ
JA
= 110°C/W,
θ
JC
= 40°C/W
ORDER INFORMATION
LEAD FREE FINISH
LTC3108EDE#PBF
LTC3108IDE#PBF
LTC3108EGN#PBF
LTC3108IGN#PBF
TAPE AND REEL
LTC3108EDE#TRPBF
LTC3108IDE#TRPBF
LTC3108EGN#TRPBF
LTC3108IGN#TRPBF
PART MARKING*
LFJM
LFJM
3108
3108
PACKAGE DESCRIPTION
12-Lead (4mm
×
3mm) Plastic DFN
12-Lead (4mm
×
3mm) Plastic DFN
16-Lead Plastic SSOP
16-Lead Plastic SSOP
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 85°C
–40°C to 85°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
3108p
2
LTC3108
ELECTRICAL CHARACTERISTICS
PARAMETER
Minimum Start-Up Voltage
No-Load Input Current
Input Voltage Range
Output Voltage
CONDITIONS
Using 1:100 Transformer Turns Ratio
Using 1:100 Transformer Turns Ratio; V
IN
= 20mV,
V
OUT2_EN
= 0V; All Outputs Charged and in Regulation
Using 1:100 Transformer Turns Ratio
VS1 = VS2 = GND
VS1 = VAUX, VS2 = GND
VS1 = GND, VS2 = VAUX
VS1 = VS2 = VAUX
V
OUT
= 3.3V, V
OUT2_EN
= 0V
No Load, All Outputs Charged
0.5mA Load
For 0mA to 2mA Load
For VAUX from 2.5V to 5V
I
LDO
= 2mA
l
l
l
l
l
l
l
l
The
l
denotes the specifications which apply over the specified operating
junction temperature range of –40°C to 85°C, otherwise specifications are at T
A
= 25°C. VAUX = 5V, unless otherwise noted.
MIN
TYP
20
3
V
STARTUP
2.30
3.234
4.018
4.90
2.350
3.300
4.100
5.000
0.4
6
2.156
2.2
0.5
0.01
100
3
4
4.5
4.5
5
5.25
0.1
1
l
MAX
50
UNITS
mV
mA
500
2.40
3.366
4.182
5.10
mV
V
V
V
V
μA
μA
V
OUT
Quiescent Current
VAUX Quiescent Current
LDO Output Voltage
LDO Load Regulation
LDO Line Regulation
LDO Dropout Voltage
LDO Current Limit
V
OUT
Current Limit
VSTORE Current Limit
VAUX Clamp Voltage
VSTORE Leakage Current
V
OUT2
Leakage Current
VS1, VS2 Threshold Voltage
VS1, VS2 Input Current
PGOOD Threshold (Rising)
PGOOD Threshold (Falling)
PGOOD V
OL
PGOOD V
OH
PGOOD Pull-Up Resistance
V
OUT2_EN
Threshold Voltage
V
OUT2_EN
Pull-Down Resistance
V
OUT2
Turn-On Time
V
OUT2
Turn-Off Time
V
OUT2
Current Limit
V
OUT2
Current Limit Response Time
V
OUT2
P-Channel MOSFET On-Resistance
N-Channel MOSFET On-Resistance
2.244
1
0.02
200
6
7
7
5.5
V
%
%
mV
mA
mA
mA
V
μA
μA
Current into VAUX = 5mA
VSTORE = 5V
V
OUT2
= 0V, V
OUT2_EN
= 0V
0.4
0.85
0.01
–7
–9
0.3
1.2
0.1
V
μA
%
%
VS1 = VS2 = 5V
Measured Relative to the V
OUT
Voltage
Measured Relative to the V
OUT
Voltage
Sink Current = 100μA
Source Current = 0
V
OUT2_EN
Rising
l
0.5
2.3
1.3
V
V
MΩ
V
MΩ
μs
μs
2.1
0.4
2.2
1
1
5
5
(Note 3)
l
0.15
0.2
0.3
350
1.3
0.5
with statistical process controls. The LTC3108I is guaranteed to meet
specifications over the full –40°C to 85°C operating temperature range.
Note 3:
Specification is guaranteed by design and not 100% tested in
production.
Note 4:
Failure to solder the exposed backside of the package to the PC
board ground plane will result in a thermal resistance much higher than
43°C/W.
0.5
A
ns
Ω
Ω
(Note 3)
V
OUT
= 3.3V (Note 3)
C2 = 5V (Note 3)
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
The LTC3108E is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
