TI LM2662 Lm266x switched capacitor voltage converter Datasheet

Product
Folder
Sample &
Buy
Support &
Community
Tools &
Software
Technical
Documents
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
LM266x Switched Capacitor Voltage Converter
1 Features
3 Description
•
•
•
•
The LM2662/LM2663 CMOS charge-pump voltage
converter inverts a positive voltage in the range of 1.5
V to 5.5 V to the corresponding negative voltage. The
LM2662/LM2663 uses two low cost capacitors to
provide 200 mA of output current without the cost,
size, and EMI related to inductor based converters.
With an operating current of only 300 μA and
operating efficiency greater than 90% at most loads,
the LM2662/LM2663 provides ideal performance for
battery powered systems. The LM2662/LM2663 may
also be used as a positive voltage doubler.
1
•
Inverts or Doubles Input Supply Voltage
3.5-Ω Typical Output Resistance
86% Typical Conversion Efficiency at 200 mA
(LM2662) Selectable Oscillator Frequency: 20
kHz/150 kHz
(LM2663) Low Current Shutdown Mode
2 Applications
•
•
•
•
•
•
Laptop Computers
Cellular Phones
Medical Instruments
Operational Amplifier Power Supplies
Interface Power Supplies
Handheld Instruments
space
space
Voltage Inverter
The oscillator frequency can be lowered by adding an
external capacitor to the OSC pin. Also, the OSC pin
may be used to drive the LM2662/LM2663 with an
external clock. For LM2662, a frequency control (FC)
pin selects the oscillator frequency of 20 kHz or 150
kHz. For LM2663, an external shutdown (SD) pin
replaces the FC pin. The SD pin can be used to
disable the device and reduce the quiescent current
to 10 μA. The oscillator frequency for LM2663 is 150
kHz.
Device Information(1)
PART NUMBER
LM2662
LM2663
PACKAGE
BODY SIZE (NOM)
SOIC (8)
4.90 mm x 3.91 mm
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
space
space
Positive Voltage Doubler
Splitting VIN in Half
* Please see Positive Voltage Doubler
section regarding choice of D1.
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
Table of Contents
1
2
3
4
5
6
7
8
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
4
4
4
4
5
6
Absolute Maximum Ratings ......................................
Handling Ratings.......................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Performance Characteristics ........................
Parameter Measurement Information .................. 9
Detailed Description ............................................ 10
8.1 Overview ................................................................. 10
8.2 Functional Block Diagram ....................................... 10
8.3 Feature Description................................................. 10
8.4 Device Functional Modes........................................ 11
9
Application and Implementation ........................ 12
9.1 Application Information............................................ 12
9.2 Typical Applications ................................................ 12
10 Power Supply Recommendations ..................... 18
11 Layout................................................................... 18
11.1 Layout Guidelines ................................................. 18
11.2 Layout Example .................................................... 18
12 Device and Documentation Support ................. 19
12.1
12.2
12.3
12.4
12.5
Device Support ....................................................
Related Links ........................................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
19
19
19
19
19
13 Mechanical, Packaging, and Orderable
Information ........................................................... 19
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision D (May 2013) to Revision E
•
Added Device Information and Handling Rating tables, Feature Description, Device Functional Modes, Application
and Implementation, Power Supply Recommendations, Layout, Device and Documentation Support, and
Mechanical, Packaging, and Orderable Information sections; moved some curves to Application Curves section .............. 1
Changes from Revision C (May 2013) to Revision D
•
2
Page
Page
Changed layout of National Data Sheet to TI format ........................................................................................................... 15
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
5 Pin Configuration and Functions
8 Pins
LM2662 SOIC (D)
Top View
8 Pins
LM2663 SOIC (D)
Top View
Pin Functions
PIN
NUMBE
R
DESCRIPTION
NAME
TYPE
FC
(LM2662)
VOLTAGE INVERTER
VOLTAGE DOUBLER
Frequency control for internal oscillator:
Input
1
FC = open, ƒOSC = 20 kHz (typ);
FC = V+, ƒOSC = 150 kHz (typ);
Same as inverter.
FC has no effect when OSC pin is driven
externally.
1
2
3
4
5
SD
(LM2663)
CAP+
GND
CAP−
OUT
Input
Shutdown control pin, tie this pin to the ground
in normal operation.
Same as inverter.
Power
Connect this pin to the positive terminal of
charge-pump capacitor.
Same as inverter.
Ground
Power supply ground input.
Power supply positive voltage input.
Power
Connect this pin to the negative terminal of
charge-pump capacitor.
Same as inverter.
Power
Negative voltage output.
Power supply ground input.
Input
Low-voltage operation input. Tie LV to GND
when input voltage is less than 3.5 V. Above
3.5 V, LV can be connected to GND or left
open. When driving OSC with an external
clock, LV must be connected to GND.
LV must be tied to OUT.
Input
Oscillator control input. OSC is connected to
an internal 15-pF capacitor. An external
capacitor can be connected to slow the
oscillator. Also, an external clock can be used
to drive OSC.
Same as inverter except that OSC cannot be
driven by an external clock.
LV
6
OSC
7
8
V+
Power
Input
Power supply positive voltage input.
Positive voltage output.
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
3
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1) (2)
MIN
MAX
Supply voltage (V+ to GND, or GND to OUT)
(OUT − 0.3 V)
LV
(GND + 3 V)
V+ and OUT continuous output current
250
Output short-circuit duration to GND (3)
Power dissipation (TA = 25°C) (4)
(4)
1
sec.
735
mW
150
Operating ambient temperature
−40
85
Operating junction temperature
−40
105
Lead temperature (soldering, 10 seconds)
(1)
(2)
(3)
(4)
V
The least negative of (OUT − 0.3 V)
or (V+ − 6 V) to (V+ + 0.3 V)
FC, OSC, SD
TJ max
UNIT
6
°C
300
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
OUT may be shorted to GND for one second without damage. However, shorting OUT to V+ may damage the device and should be
avoided. Also, for temperatures above 85°C, OUT must not be shorted to GND or V+, or device may be damaged.
The maximum allowable power dissipation is calculated by using PDMax = (TJMax − TA)/RθJA, where TJMax is the maximum junction
temperature, TA is the ambient temperature, and RθJA is the junction-to-ambient thermal resistance of the specified package.
6.2 Handling Ratings
Tstg
Storage temperature range
V(ESD)
(1)
Electrostatic discharge
MIN
MAX
UNIT
−65
150
°C
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all
pins (1)
2000
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
V+ (supply voltage)
2.5
5.5
Junction temperature (TJ)
–40
105
Ambient temperature (TJ)
–40
85
UNIT
V
°C
6.4 Thermal Information
LM2662
THERMAL METRIC (1)
LM2663
SOIC (D)
UNIT
8 PINS
RθJA
(1)
4
Junction-to-ambient thermal resistance
170
170
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
6.5 Electrical Characteristics
Unless otherwise specified: V+ = 5 V, FC = Open, C1 = C2 = 47 μF. (1)
PARAMETER
V+
TEST CONDITION
Supply Voltage
IQ
RL = 1k
Supply Current
ISD
Shutdown Supply Current
(LM2663)
VSD
Shutdown Pin Input Voltage
(LM2663)
IL
Output Current
ROUT
Output Resistance (5)
fOSC
Oscillator Frequency
5.5
Inverter, LV = GND
1.5
5.5
Doubler, LV = OUT
2.5
5.5
No Load
FC = V+ (LM2662)
LV = Open
SD = Ground
(LM2663)
1.3
4
FC = Open
0.3
0.8
Shutdown Mode
2
Normal Operation
OSC = Open
0.3
OSC = Open
FC = Open
OSC Input Current
7
20
55
150
3.5
10
27.5
75
FC = Open
PEFF
Power Efficiency
VOEFF
Voltage Conversion Efficiency
RL (500) between V+ and OUT
±10
90%
96%
99%
99.96%
IL = 200 mA to GND
(2)
(3)
(4)
(5)
(6)
(7)
No Load
7
±2
FC = V+
mA
V
mA
3.5
FC = Open
V
(4)
200
(6)
UNIT
μA
10
FC = V+
(1)
MAX (2)
3.5
IL = 200 mA
Switching Frequency (7)
IOSC
TYP (3)
Inverter, LV =
Open
FC = V+
fSW
MIN (2)
Ω
kHz
kHz
μA
86%
In the test circuit, capacitors C1 and C2 are 47-μF, 0.2-Ω maximum ESR capacitors. Capacitors with higher ESR will increase output
resistance, reduce output voltage and efficiency.
–40°C to 105°C
TJ = 25°C
In doubling mode, when Vout > 5 V, minimum input high for shutdown equals Vout − 3 V.
Specified output resistance includes internal switch resistance and capacitor ESR.
For LM2663, the oscillator frequency is 150 kHz.
The output switches operate at one half of the oscillator frequency, ƒOSC = 2ƒSW.
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
5
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
6.6 Typical Performance Characteristics
(Circuit of Figure 14 and Figure 15)
6
Figure 1. Supply Current vs Supply Voltage
Figure 2. Supply Current vs Oscillator Frequency
Figure 3. Output Source Resistance vs Supply Voltage
Figure 4. Output Source Resistance vs Temperature
Figure 5. Output Source Resistance vs Temperature
Figure 6. Output Voltage Drop vs Load Current
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
Typical Performance Characteristics (continued)
(Circuit of Figure 14 and Figure 15)
Figure 7. Output Voltage vs Oscillator Frequency
Figure 8. Oscillator Frequency vs External Capacitance
Figure 9. Oscillator Frequency vs Supply Voltage
Figure 10. Oscillator Frequency vs Supply Voltage
Figure 11. Oscillator Frequency vs Temperatur
Figure 12. Oscillator Frequency vs Temperature
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
7
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
Typical Performance Characteristics (continued)
(Circuit of Figure 14 and Figure 15)
Figure 13. Shutdown Supply Current vs Temperature (LM2663 Only)
8
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
7 Parameter Measurement Information
Figure 14. LM2662 Test Circuit
Figure 15. LM2663 Test Circuit
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
9
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
8 Detailed Description
8.1 Overview
The LM2662/LM2663 contains four large CMOS switches which are switched in a sequence to invert the input
supply voltage. Energy transfer and storage are provided by external capacitors. Figure 16 illustrates the voltage
conversion scheme. When S1 and S3 are closed, C1 charges to the supply voltage V+. During this time interval
switches S2 and S4 are open. In the second time interval, S1 and S3 are open and S2 and S4 are closed, C1 is
charging C2. After a number of cycles, the voltage across C2 will be pumped to V+. Since the anode of C2 is
connected to ground, the output at the cathode of C2 equals −(V+) assuming no load on C2, no loss in the
switches, and no ESR in the capacitors. In reality, the charge transfer efficiency depends on the switching
frequency, the on-resistance of the switches, and the ESR of the capacitors.
Figure 16. Voltage Inverting Principle
8.2 Functional Block Diagram
LM2662 (LM2663)
V+
OUT
FC(SD)
OSCILLATOR
OSC
Switch Array
Switch Drivers
LV
CAP+
CAPGND
8.3 Feature Description
8.3.1 Changing Oscillator Frequency
For the LM2662, the internal oscillator frequency can be selected using the Frequency Control (FC) pin. When
FC is open, the oscillator frequency is 20 kHz; when FC is connected to V+, the frequency increases to 150 kHz.
A higher oscillator frequency allows smaller capacitors to be used for equivalent output resistance and ripple, but
increases the typical supply current from 0.3 mA to 1.3 mA.
The oscillator frequency can be lowered by adding an external capacitor between OSC and GND (See typical
performance characteristics). Also, in the inverter mode, an external clock that swings within 100 mV of V+ and
GND can be used to drive OSC. Any CMOS logic gate is suitable for driving OSC. LV must be grounded when
driving OSC. The maximum external clock frequency is limited to 150 kHz.
The switching frequency of the converter (also called the charge pump frequency) is half of the oscillator
frequency.
NOTE
OSC cannot be driven by an external clock in the voltage-doubling mode.
10
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
Feature Description (continued)
Table 1. LM2662 Oscillator Frequency Selection
FC
OSC
OSCILLATOR
Open
Open
20 kHz
V+
Open
150 kHz
Open or V+
External Capacitor
See Typical Performance Characteristics
N/A
External Clock (inverter mode only)
External Clock Frequency
Table 2. LM2663 Oscillator Frequency Selection
OSC
OSCILLATOR
Open
150 kHz
External Capacitor
See Typical Performance Characteristics
External Clock (inverter mode only)
External Clock Frequency
8.4 Device Functional Modes
8.4.1 Shutdown Mode
For the LM2663, a shutdown (SD) pin is available to disable the device and reduce the quiescent current to 10
μA. Applying a voltage greater than 2 V to the SD pin will bring the device into shutdown mode. While in normal
operating mode, the SD pin is connected to ground.
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
11
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
9 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
9.1 Application Information
The LM2662/LM2663 CMOS charge-pump voltage converter inverts a positive voltage in the range of 1.5 V to
5.5 V to the corresponding negative voltage. The LM2662/LM2663 uses two low cost capacitors to provide 200
mA of output current without the cost, size, and EMI related to inductor based converters. With an operating
current of only 300 μA and operating efficiency greater than 90% at most loads, the LM2662/LM2663 provides
ideal performance for battery powered systems. The LM2662/LM2663 may also be used as a positive voltage
doubler.
9.2 Typical Applications
9.2.1 Simple Negative Voltage Converter
Figure 17. Simple Negative Voltage Converter
9.2.1.1 Design Requirements
The main application of LM2662/LM2663 is to generate a negative supply voltage. The voltage inverter circuit
uses only two external capacitors as shown in Figure 17. The range of the input supply voltage is 1.5 V to 5.5 V.
For a supply voltage less than 3.5 V, the LV pin must be connected to ground to bypass the internal regulator
circuitry. This gives the best performance in low voltage applications. If the supply voltage is greater than 3.5 V,
LV may be connected to ground or left open. The choice of leaving LV open simplifies the direct substitution of
the LM2662/LM2663 for the LMC7660 Switched Capacitor Voltage Converter.
9.2.1.2 Detailed Design Procedure
The output characteristics of this circuit can be approximated by an ideal voltage source in series with a resistor.
The voltage source equals −(V+). The output resistance Rout is a function of the ON resistance of the internal
MOS switches, the oscillator frequency, and the capacitance and ESR of C1 and C2. Since the switching current
charging and discharging C1 is approximately twice as the output current, the effect of the ESR of the pumping
capacitor C1 is multiplied by four in the output resistance. The output capacitor C2 is charging and discharging at
a current approximately equal to the output current, therefore, its ESR only counts once in the output resistance.
A good approximation is:
(1)
where RSW is the sum of the ON resistance of the internal MOS switches shown in the Voltage Inverting
Principle.
High value, low ESR capacitors will reduce the output resistance. Instead of increasing the capacitance, the
oscillator frequency can be increased to reduce the 2/(fosc × C1) term. Once this term is trivial compared with RSW
and ESRs, further increasing in oscillator frequency and capacitance will become ineffective.
12
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
Typical Applications (continued)
The peak-to-peak output voltage ripple is determined by the oscillator frequency, and the capacitance and ESR
of the output capacitor C2:
(2)
Again, using a low ESR capacitor will result in lower ripple.
9.2.1.2.1 Paralleling Devices
Any number of LM2662 devicess (or LM2663 devices) can be paralleled to reduce the output resistance. Each
device must have its own pumping capacitor C1, while only one output capacitor Cout is needed as shown in
Figure 18. The composite output resistance is:
(3)
Figure 18. Lowering Output Resistance by Paralleling Devices
9.2.1.2.2 Cascading Devices
Cascading the LM2662 devices (or LM2663 devices) is an easy way to produce a greater negative voltage (as
shown in Figure 19). If n is the integer representing the number of devices cascaded, the unloaded output
voltage Vout is (−nVin). The effective output resistance is equal to the weighted sum of each individual device:
(4)
A three-stage cascade circuit shown in Figure 20 generates −3 Vin, from Vin.
Cascading is also possible when devices are operating in doubling mode. In Figure 21, two devices are
cascaded to generate 3 Vin.
An example of using the circuit in Figure 20 or Figure 21 is generating +15 V or −15 V from a +5-V input.
Note that, the number of n is practically limited since the increasing of n significantly reduces the efficiency and
increases the output resistance and output voltage ripple.
Figure 19. Increasing Output Voltage by Cascading Devices
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
13
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
Typical Applications (continued)
Figure 20. Generating −3 VIN From +VIN
Figure 21. Generating +3 VIN From +VIN
9.2.1.2.3 Regulating VOUT
It is possible to regulate the output of the LM2662/LM2663 by use of a low dropout regulator (such as LP2986).
The whole converter is depicted in Figure 22. This converter can give a regulated output from −1.5 V to −5.5 V
by choosing the proper resistor ratio:
where
•
Vref = 1.23V
(5)
The error flag on pin 7 of the LP2986 goes low when the regulated output at pin 5 drops by about 5% below
nominal. The LP2986 can be shutdown by taking pin 8 low. The less than 1 μA quiescent current in the
shutdown mode is favorable for battery powered applications.
Figure 22. Combining LM2662/LM2663 With LP2986 to Make a Negative Adjustable Regulator
Also, as shown in Figure 23 by operating the LM2662/LM2663 in voltage doubling mode and adding a low
dropout regulator (such as LP2986) at the output, we can get +5 V output from an input as low as +3.3 V.
14
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
Typical Applications (continued)
Figure 23. Generating +5 V From +3.3 V Input Voltage
9.2.1.3 Application Curves
Figure 24. Efficiency vs Load Current
Figure 25. Efficiency vs Oscillator Frequency
Figure 26. Output Source Resistance vs Oscillator Frequency
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
15
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
Typical Applications (continued)
9.2.2 Positive Voltage Doubler
Figure 27. Positive Voltage Doubler
9.2.2.1 Design Requirements
The LM2662/LM2663 can operate as a positive voltage doubler (as shown in Figure 27). The doubling function is
achieved by reversing some of the connections to the device.
9.2.2.2 Detailed Design Procedure
The input voltage is applied to the GND pin with an allowable voltage from 2.5 V to 5.5 V. The V+ pin is used as
the output. The LV pin and OUT pin must be connected to ground. The OSC pin can not be driven by an external
clock in this operation mode. The unloaded output voltage is twice of the input voltage and is not reduced by the
diode D1's forward drop.
The Schottky diode D1 is only needed for start-up. The internal oscillator circuit uses the V+ pin and the LV pin
(connected to ground in the voltage doubler circuit) as its power rails. Voltage across V+ and LV must be larger
than 1.5 V to insure the operation of the oscillator. During start-up, D1 is used to charge up the voltage at V+ pin
to start the oscillator; also, it protects the device from turning-on its own parasitic diode and potentially latchingup. Therefore, the Schottky diode D1 should have enough current carrying capability to charge the output
capacitor at start-up, as well as a low forward voltage to prevent the internal parasitic diode from turning-on. A
Schottky diode like 1N5817 can be used for most applications. If the input voltage ramp is less than 10 V/ms, a
smaller Schottky diode like MBR0520LT1 can be used to reduce the circuit size.
9.2.2.3 Application Curves
See Application Curves section.
9.2.3 Splitting VIN in Half
Figure 28. Splitting VIN in Half
9.2.3.1 Design Requirements
Another interesting application shown in Figure 28 is using the LM2662/LM2663 as a precision voltage divider.
Since the off-voltage across each switch equals VIN/2, the input voltage can be raised to +11 V.
16
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
Typical Applications (continued)
9.2.3.2 Detailed Design Procedure
As discussed in the Simple Negative Voltage Converter section, the output resistance and ripple voltage are
dependent on the capacitance and ESR values of the external capacitors. The output voltage drop is the load
current times the output resistance, and the power efficiency is
(6)
IL2ROUT
Where IQ(V+) is the quiescent power loss of the IC device, and
switch on-resistance, the two external capacitors and their ESRs.
is the conversion loss associated with the
Low ESR capacitors are recommended for both capacitors to maximize efficiency, reduce the output voltage
drop and voltage ripple. For convenience, C1 and C2 are usually chosen to be the same.
The output resistance varies with the oscillator frequency and the capacitors. In Figure 26, the output resistance
vs. oscillator frequency curves are drawn for four difference capacitor values. At very low frequency range,
capacitance plays the most important role in determining the output resistance. Once the frequency is increased
to some point (such as 100 kHz for the 47-μF capacitors), the output resistance is dominated by the ON
resistance of the internal switches and the ESRs of the external capacitors. A low value, smaller size capacitor
usually has a higher ESR compared with a bigger size capacitor of the same type. Ceramic capacitors can be
chosen for their lower ESR. As shown in Figure 26, in higher frequency range, the output resistance using the
10-μF ceramic capacitors is close to these using higher value tantalum capacitors.
9.2.3.3 Application Curves
See Application Curves section.
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
17
LM2662, LM2663
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
www.ti.com
10 Power Supply Recommendations
The LM2662/LM2663 is designed to operate from as an inverter over an input voltage supply range between 1.5
V and 5.5 V when the LV pin is grounded. This input supply must be well regulated and capable to supply the
required input current. If the input supply is located far from the LM2662/LM2663 additional bulk capacitance may
be required in addition to the ceramic bypass capacitors.
11 Layout
11.1 Layout Guidelines
The high switching frequency and large switching currents of the LM2662/LM2663 make the choice of layout
important. The following steps should be used as a reference to ensure the device is stable and maintains proper
LED current regulation across its intended operating voltage and current range
• Place CIN on the top layer (same layer as the LM2662/2663) and as close to the device as possible.
Connecting the input capacitor through short, wide traces to both the V+ and GND pins reduces the inductive
voltage spikes that occur during switching which can corrupt the V+ line.
• Place COUT on the top layer (same layer as the LM2662/2663) and as close as possible to the OUT and GND
pin. The returns for both CIN and COUT should come together at one point, as close to the GND pin as
possible. Connecting COUT through short, wide traces reduce the series inductance on the OUT and GND
pins that can corrupt the VOUT and GND lines and cause excessive noise in the device and surrounding
circuitry.
• Place C1 on the top layer (same layer as the LM2662/2663) and as close to the device as possible. Connect
the flying capacitor through short, wide traces to both the CAP+ and CAP– pins.
11.2 Layout Example
LM2662 (LM2663)
V+
OUT
FC(SD)
OSCILLATOR
OSC
Switch Array
Switch Drivers
LV
18
CAP+
CAPGND
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
LM2662, LM2663
www.ti.com
SNVS002E – JANUARY 1999 – REVISED OCTOBER 2014
12 Device and Documentation Support
12.1 Device Support
12.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
12.2 Related Links
Table 3 lists quick access links. Categories include technical documents, support and community resources,
tools and software, and quick access to sample or buy.
Table 3. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
LM2662
Click here
Click here
Click here
Click here
Click here
LM2663
Click here
Click here
Click here
Click here
Click here
12.3 Trademarks
All trademarks are the property of their respective owners.
12.4 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
12.5 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
13 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Submit Documentation Feedback
Copyright © 1999–2014, Texas Instruments Incorporated
Product Folder Links: LM2662 LM2663
19
PACKAGE OPTION ADDENDUM
www.ti.com
15-Aug-2014
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
LM2662M
NRND
SOIC
D
8
95
TBD
Call TI
Call TI
-40 to 85
LM26
62M
LM2662M/NOPB
ACTIVE
SOIC
D
8
95
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
LM26
62M
LM2662MX/NOPB
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
LM26
62M
LM2663M
NRND
SOIC
D
8
95
TBD
Call TI
Call TI
-40 to 85
LM26
63M
LM2663M/NOPB
ACTIVE
SOIC
D
8
95
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
LM26
63M
LM2663MX
NRND
SOIC
D
8
2500
TBD
Call TI
Call TI
-40 to 85
LM26
63M
LM2663MX/NOPB
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
LM26
63M
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
15-Aug-2014
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
18-Aug-2014
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM2662MX/NOPB
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2663MX
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2663MX/NOPB
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
18-Aug-2014
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM2662MX/NOPB
SOIC
D
8
2500
367.0
367.0
35.0
LM2663MX
SOIC
D
8
2500
367.0
367.0
35.0
LM2663MX/NOPB
SOIC
D
8
2500
367.0
367.0
35.0
Pack Materials-Page 2
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale
supplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of
non-designated products, TI will not be responsible for any failure to meet ISO/TS16949.
Products
Applications
Audio
www.ti.com/audio
Automotive and Transportation
www.ti.com/automotive
Amplifiers
amplifier.ti.com
Communications and Telecom
www.ti.com/communications
Data Converters
dataconverter.ti.com
Computers and Peripherals
www.ti.com/computers
DLP® Products
www.dlp.com
Consumer Electronics
www.ti.com/consumer-apps
DSP
dsp.ti.com
Energy and Lighting
www.ti.com/energy
Clocks and Timers
www.ti.com/clocks
Industrial
www.ti.com/industrial
Interface
interface.ti.com
Medical
www.ti.com/medical
Logic
logic.ti.com
Security
www.ti.com/security
Power Mgmt
power.ti.com
Space, Avionics and Defense
www.ti.com/space-avionics-defense
Microcontrollers
microcontroller.ti.com
Video and Imaging
www.ti.com/video
RFID
www.ti-rfid.com
OMAP Applications Processors
www.ti.com/omap
TI E2E Community
e2e.ti.com
Wireless Connectivity
www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2014, Texas Instruments Incorporated
Similar pages