Super Capacitor - NIC Components Corp.

Rev A - May 2009
www.NICcomp.com
Technical support: [email protected]
Double Layer Capacitors
PN: NEX_ series & NED_ series
NEXC
SMT
Reflow
Soldering
NEXA / NEXG
NEXS / NEXT
Low Profile
Radial LDD
NEXM
Molded
Radial LDD
NEDL
NEDR
Large Case
Radial LDD
Double Layer Capacitors
Also known as super capacitors, gold capacitors, ultra capacitors and farad capacitors
All belong to the family of electro-chemical double layer capacitors abbreviated EDLCs
Feature high capacitance value (Farad) for energy storage, voltage hold-up and battery back-up
applications. Double layer capacitors bridge the gap (see graph below) between conventional
batteries and conventional capacitors. EDLCs store and deliver temporary (or momentary) energy
to electronic circuits in wide range of low voltage (2 ~ 12VDC) circuit applications.
Double Layer
Capacitors
Wh = watt-hour
is unit of energy
equivalent to one
watt (1 W) of
power expended
for one hour
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
Selection Guide: Series – Type
NIC Series
NEXC
-25°C ~ +70°C
NEXM
-25°C ~ +70°C
Type
Size (mm)
Capacitance
Voltage
SMT Chip
10.5 Ø x 5.5 height
10.5 Ø x 8.5 height
10.7 Ø x 5.5 height
16 Ø x 9.5 height
21 Ø x 10.5 height
0.047F ~ 1.0F
(47,000 μF ~
1,000,000 μF)
3.5VDC
5.5VDC
Radial LDD
Molded
Case
5mm LS
10.5 x 11.5 x 5.0
10.5 x 11.5 x 6.5
0.01F ~ 0.22F
(10,000μF ~
220,000μF)
3.5VDC
6.5VDC
10F ~ 100F
2.5VDC
2.7VDC
NEDL
-25°C ~ +70°C
NEDR
-25°C ~ +60°C
-25°C ~ +70°C
NEXA
NEXG
NEXS
-25°C ~ +70°C
NEXT
-40°C ~ +85°C
Radial LDD
Large Can
Radial LDD
Low Profile
10 Ø x 35 height
12.5 Ø x 25 height
12.5 Ø x 35 height
16 Ø x 35.5 height
18 Ø x 40 height
18 Ø x 50 height
22 Ø x 50 height
22 Ø x 65 height
11 Ø x 5.5 / 6.5 / 8.5
13 Ø x 8.5 / 9
14.5 Ø x 12 / 18
16 Ø x 15.5 / 25
16.5 Ø x 8.5 / 13 / 19
21.5 Ø x 13 / 15.5 / 19
28.5 Ø x 16.5 / 14 / 19 / 22 /
25.5 / 31.5 / 38
36.5 Ø x 15 / 16.5 / 27.5
44.5 Ø x 17 / 18.5 / 28.5 / 60
ISO 9001:2000
0.01F ~ 5.6F
(10,000μF ~
5,600,000μF)
REGISTERED
5.5VDC
11VDC
12VDC
RE: Double Layer Capacitors
NEX_ Series Construction:
Double Layer Cell (~ 1.2VDC breakdown)
The liquid electrolyte is sealed
within the capacitor element
by rubber sealing material
Multiple cells are connected in
series, to increase the voltage
rating of the capacitor
NEXT
NEXM
NEXC
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
Precautions for Use:
Circuit Design
Voltage:
o
Only direct current (VDC) should be applied to double layer capacitors
o
Ensure that the maximum operating voltage does not exceed the rated voltage (VDC)
o
Application of a voltage exceeding the maximum operating voltage may deteriorate performance
and damage the component.
Polarity:
Double layer capacitors are polarized (anode + terminal and cathode – terminal).
Please assure correct polarity when installing (or placing) component during PCB assembly.
Components have polarity indicators as follows:
o
NEXC – SMT; Anode (+) notch in base-plate and top of can Cathode (-) indicator (See Image)
o
NEXM – Molded case radial leaded; Polarity (+ & -) indicators on case (See Image)
o
NEXA, NEXG, NEXS, NEXT – Radial leaded; Cathode (-) indicators on sleeve and case (See Image)
Equivalent Series Resistance (ESR):
ESR of double layer capacitors is relatively high. Do not use double layer capacitors in supply voltage
smoothing circuits, such as output filter of power supply circuits
Parallel connection of multiple double layer capacitors is possible; please assure the voltage applied to
each capacitor does not exceed the maximum operating voltage (VDC).
For series connection of multiple double layer capacitors, please take measures to ensure voltage is
evenly distributed to all capacitors and the voltage applied to each capacitor does not exceed the
maximum operating voltage (VDC).
Mounting - Soldering
a. All radial leaded versions of double layer capacitors cannot withstand exposure to reflow
soldering heat. Only NEXC series can be used in reflow soldering process.
b. When using flow – wave soldering process, ensure that the soldering temperature is ≤260 °C and
soldering duration does not exceed 10 seconds
c. For soldering with a soldering rod, select a soldering rod with a capacity of ~30W and ensure that the
tip temperature <400°C and soldering duration is less than 3 seconds
d. Excessive soldering heat may increase the equivalent series resistance (ESR) of the capacitor
d. Do not bend, deform or file capacitor terminals and take measures to prevent mechanical impact
damage to terminals. Impact to terminals may cause damage to plating and result in poor soldering.
e. All capacitors, including those with insulation sleeving should not contact adjacent components nor
contact assembly case
f. Use in the vicinity of a heating element (coil, power transistor, resistor, etc.) may heat the capacitor
itself and considerably shorten its service life
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
Precautions for Use:
Residual Charge
Take precautions, as some residual potential (applied during manufacturing test) may be present on
double layer capacitors as received. Voltage recovery over time may result in residual charge on
component after time in transit and on shelf. Please take measures to avoid damage to other components
(i.e. semiconductors) during PC assembly.
Environment
Double layer capacitors cannot be used in an acidic or alkaline atmospheres or liquids
Washing
o
o
Do not wash double layer capacitors, except NEXM series, without reviewing washing conditions
with NIC technical support [ [email protected] ]. Special washing-resistant versions may be
available.
Drying after washing of NEXM series, should be performed within the maximum operating
temperature range [< +70°C].
Storage
a. Storage Conditions:
o
Indoors
o
Temperature: +5°C ~ +35°C (41°F ~ 95°F)
o
Relative humidity: 40 to 75%
b. Avoid exposing the components to direct sunlight for extended periods. Doing so may cause
deterioration or discoloration of the insulation sleeving
c. Do not store in an alkaline or acidic atmosphere.
Disassembly & Disposal
o
o
o
o
Do not disassemble capacitor
The capacitor electrolyte contains a trace amount of dilute sulfuric acid.
Avoid contact as may have a harmful effect
Do not use incineration for disposal. Instead, dispose of capacitor as industrial waste
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
Component Selection Guide
If backup current requirement is 1 mA or greater
NEXA, NEXM, NEXS, NEXT, NEDL and NEDR series are suggested
See discharge
characteristics in
Appendix “A”
An approximate backup time can be calculated from the following expression:
T (seconds) = [ C × (V0 – V1 – Vdrop) ]
I
C : Double layer capacitor capacitance (Farad)
V0 : Voltage charged in double layer capacitor (VDC)
Vdrop : Voltage drop by DC resistance with double layer capacitor (VDC)
V1 : Minimum required voltage for backup circuit (VDC)
I : Backup current (Amp)
The voltage drop is determined by the DC resistance of the capacitor and backup current
Vdrop (VDC) = DCR * I … DCR = Ω & I = A
Example #1:
1.0F 5.5VDC, DCR = 1.1Ω, NIC PN: NEXA105Z5.5V44.5FX18.5F
o
Circuit Back-up Current; I = 1000uA (1mA)
o
Vdrop = 0.0011
o
V0= 5.0VDC
o
V1 = 3.3VDC
Back-up Time (T) = 1699 seconds (28 minutes)
Example #2:
1.0F 5.5VDC, DCR = 1.1Ω, NIC PN: NEXA105Z5.5V44.5FX18.5F
o
Circuit Back-up Current; I = 5000uA (5mA)
o
Vdrop = 0.0055
o
V0= 5.0VDC
o
V1 = 3.3VDC
Back-up Time (T) = 339 seconds (5.65 minutes)
If backup current requirement is less than1 mA ; NEXC, NEXG, NEXM series are suggested
An approximate backup time can be calculated from constant resistance discharge characteristics
obtained by converting the back-up current requirement to a constant resistance load
See discharge
characteristics in
Appendix “A”
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
Explanation of Characteristics Terms
1.0 Charging Time & Current
Double layer capacitors require much longer time to charge than conventional capacitors.
For example; conventional aluminum or tantalum electrolytic capacitors charge, to the applied voltage
(VDC), within a relatively short period of time (typically within seconds or minutes, depending upon
Capacitance-Voltage). Leakage current characteristics for aluminum or tantalum electrolytic capacitors is
usually specified in micro-Amperes (uA) after one or two minutes of charging (LC = 0.01CV after 2 minutes).
Double layer capacitors require many hours to fully charge (100+ Hours), so the typical method of
measure leakage current is not applicable with respect to double layer capacitors. Most of the current
flowing into a double layer capacitor after 30 minutes is charging current rather then leakage current.
Typical charging currents after 1 hour of charge, can be between 100uA ~ 3mA ( GRAPH 1 )
GRAPH 1
Double Layer Capacitors
5.5VDC Charge Current Characteristics
300 Hours Charge
10,000.0
Charging
Charged
100.0
NEXC
NEXH
NEXS
NEXT
3.3F NEXT
10.0
NEXTH
1.0F NEXS
0.47F NEXH
0.47F
1.0
0.47F NEXC
1 Hr
10 Hr
100Hr
ISO 9001:2000
ur
s
ho
6
33
ho
ur
s
ur
s
REGISTERED
0
ho
Time of Charge
27
ho
ur
s
0
20
10
0
ho
ur
s
ho
ur
s
50
75
ur
s
ho
25
ur
s
s
10
ho
s
ho
ur
5
ho
ur
ho
ur
2
1
te
s
m
in
ut
es
30
m
in
ut
es
in
u
10
ut
e
m
5
m
in
1
se
co
n
ds
0.1
30
Charge Current (uA)
1,000.0
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
Charge Current over Time
11VDC
0.47 Farad
0.22 Farad
0.10 Farad
0.022 Farad
Higher capacitance value (Farad)
Results in higher charge current (uA)
5.5VDC
1.0 Farad
0.47 Farad
0.22 Farad
0.10 Farad
Higher capacitance value (Farad)
Results in higher charge current (uA)
0.047 Farad
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
2.0 Discharge Rate (via connecting circuitry)
The rate of discharge of double layer capacitors will be determined by the resistance of
connecting circuitry ( GRAPH 2 ).
Discharge Tips:
o
Increasing circuit resistance extends discharge rate
o
Longer charging time will extend discharge rate
GRAPH 2
See discharge
characteristics in
Appendix “A”
Increasing circuit resistance
extends discharge rate
3.0 Voltage Holding Characteristic (self-discharge)
Self-discharge of double layer capacitors is characterized via the "Voltage Holding
Characteristic" as shown on specification sheets, and specifies the minimum voltage after 24
hours at room temperature after the part has been charged for 24 hours at the rated voltage.
Example: NEXG and NEXC series for power back-up applications:
Holding Voltage = 4.2VDC (for 5.5VDC rated components) is the minimum voltage on
the capacitor after 24 hours charge at 5.5VDC, followed by 24 hour period (+25°C) with
no circuitry load resistance applied.
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
PN: NEX_ series & NED_ series
4.0 Capacitance Value
Due to the very large capacitance and relatively high ESR of double layer capacitors the
capacitance value cannot be measured using standard capacitance meters. Two methods are
used to determine the capacitance value of double layer capacitors:
Charging Method:
1.
Constant resistance charge method - Capacitance value test
o
Prep component by shorting terminals for 30 minutes prior to capacitance value test
o
Capacitance (F) is calculated by measuring the time constant (t) until capacitor voltage
reaches 0.632 of applied VDC (Eo)
o
Rc is fixed resistance value
o
2.
Capacitance (Farads) = t/Rc
Constant current charge – discharge method - Capacitance value test
o
Test method similar to common circuit application
o
As discharge current increases the capacitance value will decrease as shown in example
below
o
Note: At low discharge currents the capacitance value may be 130 ~ 150% of nominal
value, as shown in below graph (GRAPH 3)
GRAPH 3
Nominal Value = 0.047F
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
5.0 Life Time
Double layer capacitors, much like aluminum electrolytic capacitors, have a limited service life,
electrolyte will dissipate over time (and operating temperature) from the component, resulting
component wear-out. Lifetime estimation will be chiefly governed by operating temperature and can
estimated from graph “Capacitor Temperature Acceleration” (GRAPH 4). Lifetime is defined as point
which capacitance value is reduced by 70% of the initial capacitance value.
as
in
be
at
Failure mode of double layer capacitors is "open" mode under normal conditions, but short-circuit
may result if extreme voltage, exceeding the maximum operating voltage is applied to the
component. Water vapor, generated from water within the electrolyte (dilute sulfuric acid), gradually
dissipates from the component in from of gas and is not dangerous. However, if unusual voltage such as
greater than the maximum operating voltage is applied suddenly, leakage of liquid electrolyte or
rupturing of component may result. When used for long periods at high operating temperature, the
moisture of the electrolyte evaporates and the equivalent series resistance (ESR) increases. The
fundamental failure mode is the open mode with ESR increase.
When using these capacitors, incorporate appropriate safety measures in your design, such as
redundancy and protection measures.
Failure Rate- FIT: FIT rate for double layers capacitors is estimated to be 0.06 FIT
GRAPH 4
Longer Life
Decreasing
Temperature
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
6.0 Temperature Characteristics:
Typical Capacitance Change over Temperature (-25°C ~ +70°C)
(Condition: –25°C Î +25°C Î +70°C, n = 10)
SUMMARY: Increased capacitance as temperature increases
Typical 1KHz ESR Change over Temperature (-25°C ~ +70°C)
Equivalent
Series
Resistance;
sum of resistive
losses within
the capacitor
(Condition: –25°C
Î +25°C Î
+70°C, n = 10)
SUMMARY: Decreasing ESR as temperature increases
ISO 9001:2000
REGISTERED
RE: Double Layer Capacitors
Typical Discharge Characteristics over Temperature (+25°C, +50°C, +60°C & +70°C)
SUMMARY: Decreasing charge as temperature increases
ISO 9001:2000
REGISTERED
Appendix “A”
APPENDIX “A”
RE: Double Layer Capacitors
Constant Resistance Discharge Characteristics
100 Farad / 2.7VDC
NEDL
NEDR
50 Farad / 2.7VDC
ISO 9001:2000
REGISTERED
APPENDIX “A”
RE: Double Layer Capacitors
Constant Resistance Discharge Characteristics
22 Farad / 2.7VDC
10 Farad / 2.7VDC
ISO 9001:2000
REGISTERED
Appendix “A”
Appendix “A”
APPENDIX “A”
RE: Double Layer Capacitors
Constant Resistance Discharge Characteristics
NEXC
ISO 9001:2000
REGISTERED
APPENDIX “A”
Appendix “A”
RE: Double Layer Capacitors
Constant Resistance Discharge Characteristics
NEXC
ISO 9001:2000
REGISTERED
APPENDIX “A”
Appendix “A”
RE: Double Layer Capacitors
Constant Resistance Discharge Characteristics
NEXC
ISO 9001:2000
REGISTERED
APPENDIX “A”
RE: Double Layer Capacitors
Constant Resistance Discharge Characteristics
0.47 Farad / 5.5VDC
1.0 Farad / 5.5VDC
ISO 9001:2000
REGISTERED
Appendix “A”
APPENDIX “A”
RE: Double Layer Capacitors
Constant Resistance Discharge Characteristics
ISO 9001:2000
REGISTERED
Appendix “A”