LM2705MF-ADJ/NOPB [TI]

具有 150mA 峰值电流限制的微功耗升压直流/直流转换器 | DBV | 5 | -40 to 85;
LM2705MF-ADJ/NOPB
型号: LM2705MF-ADJ/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

具有 150mA 峰值电流限制的微功耗升压直流/直流转换器 | DBV | 5 | -40 to 85

转换器
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LM2705  
SNVS191F NOVEMBER 2002REVISED OCTOBER 2016  
LM2705 Micropower Step-Up DC-DC Converter With 150-mA Peak Current Limit  
1 Features  
3 Description  
The LM2705 is  
converter in a small 5-pin SOT-23 package. A  
current-limited, fixed-off-time control scheme  
a micropower step-up DC-DC  
1
2.2-V to 7-V Input Range  
150-mA, 0.7-Internal Switch  
Adjustable Output Voltage up to 20 V  
Input Undervoltage Lockout  
conserves operating current, which results in high  
efficiency over a wide range of load conditions. The  
21-V switch allows for output voltages as high as  
20 V. The low 400-ns off-time permits the use of tiny,  
low-profile inductors and capacitors to minimize  
footprint and cost in space-conscious portable  
applications. The LM2705 is ideal for LCD panels  
requiring low current and high efficiency as well as  
white-LED applications for cellular phone back-  
lighting. The LM2705 device can drive up to 3 white  
LEDs from a single Li-Ion battery. The low peak-  
inductor current of the LM2705 makes it ideal for USB  
applications.  
0.01-µA Shutdown Current  
Uses Small Surface-Mount Components  
Small 5-Pin SOT-23 Package  
2 Applications  
LCD Bias Supplies  
White-LED Backlighting  
Handheld Devices  
Digital Cameras  
Device Information(1)  
Portable Applications  
PART NUMBER  
LM2705  
PACKAGE  
BODY SIZE (NOM)  
SOT-23 (5)  
2.90 mm × 1.60 mm  
(1) For all available packages, see the orderable addendum at  
the end of the data sheet.  
space  
space  
space  
Typical 20-V Application  
L
20 V  
68 mH  
D
6 mA  
VIN = Li-Ion  
5
1
R1  
510 k  
SW  
VIN  
CIN  
4.7 mF  
LM2705  
COUT  
1 mF  
3
4
SHDN  
FB  
R2  
33 kΩ  
GND  
2
Copyright © 2016, Texas Instruments Incorporated  
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.  
 
 
 
 
LM2705  
SNVS191F NOVEMBER 2002REVISED OCTOBER 2016  
www.ti.com  
Table of Contents  
1
2
3
4
5
6
Features.................................................................. 1  
Applications ........................................................... 1  
Description ............................................................. 1  
Revision History..................................................... 2  
Pin Configuration and Functions......................... 3  
Specifications......................................................... 4  
6.1 Absolute Maximum Ratings ...................................... 4  
6.2 ESD Ratings.............................................................. 4  
6.3 Recommended Operating Conditions....................... 4  
6.4 Thermal Information.................................................. 4  
6.5 Electrical Characteristics........................................... 5  
6.6 Typical Characteristics.............................................. 6  
Detailed Description .............................................. 8  
7.1 Overview ................................................................... 8  
7.2 Functional Block Diagram ......................................... 8  
7.3 Feature Description................................................... 8  
7.4 Device Functional Modes.......................................... 8  
8
Application and Implementation .......................... 9  
8.1 Application Information.............................................. 9  
8.2 Typical Application ................................................... 9  
8.3 Additional Applications............................................ 12  
Power Supply Recommendations...................... 15  
9
10 Layout................................................................... 15  
10.1 Layout Guidelines ................................................. 15  
10.2 Layout Example .................................................... 15  
11 Device and Documentation Support ................. 16  
11.1 Device Support...................................................... 16  
11.2 Receiving Notification of Documentation Updates 16  
11.3 Community Resources.......................................... 16  
11.4 Trademarks........................................................... 16  
11.5 Electrostatic Discharge Caution............................ 16  
11.6 Glossary................................................................ 16  
7
12 Mechanical, Packaging, and Orderable  
Information ........................................................... 16  
4 Revision History  
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.  
Changes from Revision E (May 2013) to Revision F  
Page  
Added Device Information and Pin Configuration and Functions sections, ESD Ratings and Thermal Information  
tables, Feature Description, Device Functional Modes, Application and Implementation, Power Supply  
Recommendations, Layout, Device and Documentation Support, and Mechanical, Packaging, and Orderable  
Information sections................................................................................................................................................................ 1  
Deleted pin definition list - added content to Pin Functions .................................................................................................. 3  
Changed RθJA value from "220°C/W" to "164.9°C/W" ........................................................................................................... 4  
Changes from Revision D (May 2013) to Revision E  
Page  
Changed layout of National Semiconductor data sheet to TI format.................................................................................... 14  
2
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5 Pin Configuration and Functions  
DBV Package  
5-Pin SOT-23  
Top View  
VIN  
SW  
GND  
FB  
SHDN  
Pin Functions  
PIN  
TYPE  
DESCRIPTION  
NO.  
NAME  
SW  
1
Power switch input. This is the drain of the internal NMOS power switch. Minimize the metal  
trace area connected to this pin to minimize EMI.  
Input  
2
3
GND  
FB  
Ground - tie directly to ground plane.  
Output voltage feedback input — set the output voltage by selecting values for R1 and R2 using:  
R1 = R2 × (VOUT / 1.237 V) –1  
Input  
4
5
Active low shutdown - drive this pin to > 1.1 V to enable the device. Drive this pin to < 0.3 V to  
lace the device in a low-power shutdown.  
SHDN  
VIN  
Input  
Input  
Analog and power input supply pin  
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6 Specifications  
6.1 Absolute Maximum Ratings  
over operating free-air temperature range (unless otherwise noted)(1)(2)  
MIN  
MAX  
7.5  
21  
UNIT  
V
VIN  
SW voltage  
FB voltage  
SHDN voltage  
V
2
V
7.5  
150  
300  
215  
220  
150  
V
(3)  
Maximum junction temperature, TJ  
°C  
°C  
°C  
°C  
°C  
Soldering (10 seconds)  
Lead temperature  
Vapor phase (60 seconds)  
Infrared (15 seconds)  
Storage temperature, Tstg  
–65  
(1) 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.  
(2) If Military/Aerospace specified devices are required, contact the TI Sales Office/Distributors for availability and specifications.  
(3) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal  
resistance, RθJA, and the ambient temperature, TA. See Thermal Information for the thermal resistance. The maximum allowable power  
dissipation at any ambient temperature is calculated using: PD(MAX) = (TJ(MAX) TA) / RθJA. Exceeding the maximum allowable power  
dissipation will cause excessive die temperature.  
6.2 ESD Ratings  
VALUE  
±2000  
±200  
UNIT  
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)  
Machine model(2)  
V(ESD)  
Electrostatic discharge  
V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.  
(2) ESD susceptibility using the machine model is 150 V for SW pin.  
6.3 Recommended Operating Conditions  
over operating free-air temperature range (unless otherwise noted)  
MIN  
NOM  
MAX  
7
UNIT  
V
Supply voltage  
2.2  
SW voltage, maximum  
Junction temperature(1)  
20.5  
125  
V
–40  
°C  
(1) All limits specified at room temperature and at temperature extremes. All room temperature limits are 100% production tested or  
specified through statistical analysis. All limits at temperature extremes are specified via correlation using standard statistical quality  
control (SQC) methods. All limits are used to calculate average outgoing quality level (AOQL).  
6.4 Thermal Information  
LM2705  
THERMAL METRIC(1)  
DBV (SOT-23)  
5 PINS  
164.9  
UNIT  
RθJA  
RθJC(top)  
RθJB  
ψJT  
Junction-to-ambient thermal resistance  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
Junction-to-case (top) thermal resistance  
Junction-to-board thermal resistance  
116.8  
27.8  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
13.6  
ψJB  
27.3  
(1) For more information about traditional and new thermal metrics, see Semiconductor and IC Package Thermal Metrics.  
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6.5 Electrical Characteristics  
Unless otherwise specified, specifications apply for TJ = 25°C and VIN = 2.2 V.  
MAX  
PARAMETER  
TEST CONDITIONS  
MIN(1)  
TYP(2)  
UNIT  
(1)  
FB = 1.3 V  
40  
Device disabled  
FB = 1.3 V, –40°C to 125°C  
FB = 1.2 V  
70  
IQ  
235  
µA  
Device enabled  
Shutdown  
FB = 1.2 V, –40°C to 125°C  
SHDN = 0 V  
300  
2.5  
0.01  
1.237  
VFB  
Feedback trip point  
V
–40°C to 125°C  
1.189  
100  
1.269  
180  
150  
30  
ICL  
Switch current limit  
mA  
–40°C to 125°C  
FB = 1.23 V(3)  
FB = 1.23 V, –40°C to 125°C(3)  
IB  
FB pin bias current  
Input voltage  
nA  
V
120  
7
VIN  
–40°C to 125°C  
2.2  
0.7  
RDSON  
TOFF  
Switch RDSON  
Switch off time  
–40°C to 125°C  
1.6  
80  
400  
0
ns  
SHDN = VIN, TJ = 25°C  
SHDN = VIN, TJ = 125°C  
SHDN = GND  
ISD  
SHDN pin current  
15  
nA  
0
IL  
Switch leakage current  
VSW = 20 V  
0.05  
1.8  
5
µA  
V
UVP  
Input undervoltage lockout  
ON/OFF threshold  
VFB  
hysteresis  
Feedback hysteresis  
SHDN low  
8
mV  
0.7  
–40°C to 125°C  
–40°C to 125°C  
0.3  
SHDN  
threshold  
V
0.7  
SHDN high  
1.1  
(1) All limits specified at room temperature and at temperature extremes. All room temperature limits are 100% production tested or  
specified through statistical analysis. All limits at temperature extremes are specified via correlation using standard statistical quality  
control (SQC) methods. all limits are used to calculate average outgoing quality level (AOQL).  
(2) Typical numbers are at 25°C and represent the most likely norm.  
(3) Feedback current flows into the pin.  
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6.6 Typical Characteristics  
Figure 1. Enable Current vs VIN (Device Switching)  
Figure 2. Disable Current vs VIN (Device Not Switching)  
Figure 3. SHDN Threshold vs VIN  
Figure 4. Switch Current Limit vs VIN  
1.25  
1.24  
1.23  
1.22  
1.21  
1.20  
55  
50  
45  
40  
35  
30  
25  
20  
15  
ë
n!  
-40 -20  
0
20 40 60 80 100 120  
WÜb/ÇLhb Ç9at9w!ÇÜw9 (°/)  
Figure 5. Switch RDSON vs VIN  
Figure 6. FB Trip Point and FB Pin Current vs Temperature  
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Typical Characteristics (continued)  
Figure 8. Off Time vs Temperature  
Figure 7. Output Voltage vs Load Current  
1) Load: 0.5 mA to 5 mA to 0.5 mA, DC  
2) VOUT: 200 mV/div, AC  
VOUT = 20 V  
1) SHDN: 1 V/div, DC  
2) VOUT: 10 V/div, AC  
3. IL: 100 mA/div, DC  
VIN = 3 V  
VOUT = 20 V  
VIN = 3 V  
T = 100 µs/div  
RL = 3.9 kΩ  
3. IL: 100 mA/div, DC  
T = 100 µs/div  
Figure 9. Step Response  
Figure 10. Start-Up and Shutdown  
1. VSW: 20 V/div, DC  
VIN = 2.7 V  
VOUT = 20 V  
2. Inductor Current: 100 mA/div, DC  
3. VOUT, 200 mV/div, AC  
IOUT = 2.5 mA  
Figure 11. Typical Switching Waveform  
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7 Detailed Description  
7.1 Overview  
The LM2705 is a small boost converter utilizing a constant off time architecture. The device can provide up to  
20.5 V at the output with up to 150 mA of peak switch current.  
7.2 Functional Block Diagram  
L
D
VIN  
VOUT  
VIN  
SW  
5
1
CIN  
COUT  
R2  
50 kΩ  
R1  
50 kΩ  
Enable  
Comp  
VOUT  
+
Enable  
-
RF1  
FB  
Q2  
10x  
Q1  
3
+
RF2  
CL  
Comp  
-
R3  
30 kΩ  
Current Sensing  
Circuitry  
400ns  
One Shot  
CL  
Adjust  
Driver  
Logic  
R4  
140 kΩ  
Undervoltage  
Lockout  
4
2
GND  
SHDN  
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7.3 Feature Description  
The LM2705 device features a constant off-time control scheme. Operation can be best understood by referring  
to Functional Block Diagram and Figure 11. Transistors Q1 and Q2 and resistors R3 and R4 of Functional Block  
Diagram form a bandgap reference used to control the output voltage. When the voltage at the FB pin is less  
than 1.237 V, the Enable Comp in Functional Block Diagram enables the device, and the NMOS switch is turned  
on pulling the SW pin to ground. When the NMOS switch is on, current begins to flow through inductor L while  
the load current is supplied by the output capacitor COUT. Once the current in the inductor reaches the current  
limit, the CL comp trips, and the 400-ns one shot turns off the NMOS switch.The SW voltage then rises to the  
output voltage plus a diode drop, and the inductor current begins to decrease as shown in Figure 11. During this  
time the energy stored in the inductor is transferred to COUT and the load. After the 400-ns off-time the NMOS  
switch is turned on, and energy is stored in the inductor again. This energy transfer from the inductor to the  
output causes a stepping effect in the output ripple as shown in Figure 11.  
This cycle is continued until the voltage at FB reaches 1.237 V. When FB reaches this voltage, the Enable Comp  
disables the device, turning off the NMOS switch and reducing the IQ of the device to 40 µA. The load current is  
then supplied solely by COUT indicated by the gradually decreasing slope at the output as shown in Figure 11.  
When the FB pin drops slightly below 1.237 V, the Enable Comp enables the device and begins the cycle  
described previously.  
7.4 Device Functional Modes  
The SHDN pin can be used to turn off the LM2705 and reduce the IQ to 0.01 µA. In shutdown mode the output  
voltage is a diode drop lower than the input voltage.  
8
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8 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.  
8.1 Application Information  
The LM2705 is a 20-V boost designed for low power boost applications. Typical input voltage range makes this  
ideal for standard single cell Li+ batteries or 2 to 4 series alkaline batteries.  
8.2 Typical Application  
Figure 12 shows a typical Li+ voltage range to 20-V application. The 68-µH inductor allows for a low ripple  
current and high light-load efficiency.  
L
20 V  
68 mH  
D
6 mA  
VIN = Li-Ion  
5
1
R1  
510 k  
SW  
VIN  
CIN  
4.7 mF  
LM2705  
COUT  
1 mF  
4
3
SHDN  
FB  
R2  
33 kΩ  
GND  
2
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Figure 12. Typical 20-V Application  
8.2.1 Design Requirements  
For typical DC-DC converter applications, use the parameters listed in Table 1.  
Table 1. Design Parameters  
DESIGN PARAMETER  
Input voltage  
EXAMPLE VALUE  
2.5 V to 4.2 V  
12 V  
Output voltage  
Output current  
Inductor  
up to 8 mA  
33 µH  
8.2.2 Detailed Design Procedure  
8.2.2.1 Inductor Selection - Boost Regulator  
The appropriate inductor for a given application is calculated using Equation 1:  
(
VOUT - VIN(min) + VD  
L =  
TOFF  
(
ICL  
where  
VD is the Schottky diode voltage  
ICL is the switch current limit found in the Typical Characteristics  
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TOFF is the switch off time  
(1)  
When using this equation be sure to use the minimum input voltage for the application, such as for battery  
powered applications. For the LM2705 constant-off time control scheme, the NMOS power switch is turned off  
when the current limit is reached. There is approximately a 100-ns delay from the time the current limit is  
reached in the NMOS power switch and when the internal logic actually turns off the switch. During this 100-ns  
delay, the peak inductor current increases. This increase in inductor current demands a larger saturation current  
rating for the inductor. This saturation current can be approximated by Equation 2:  
VIN(max)  
«
100 ns  
IPK = ICL  
+
L
(2)  
Choosing inductors with low ESR decrease power losses and increase efficiency.  
Take care when choosing an inductor. For applications that require an input voltage that approaches the output  
voltage, such as when converting a Li-Ion battery voltage to 5 V, the 400-ns off time may not be enough time to  
discharge the energy in the inductor and transfer the energy to the output capacitor and load. This can cause a  
ramping effect in the inductor current waveform and an increased ripple on the output voltage. Using a smaller  
inductor causes the IPK to increase and increases the output voltage ripple further.  
For typical curves and evaluation purposes the DT1608C series inductors from Coilcraft were used. Other  
acceptable inductors include, but are not limited to, the SLF6020T series from TDK, the NP05D series from Taiyo  
Yuden, the CDRH4D18 series from Sumida, and the P1166 series from Pulse.  
8.2.2.2 Inductor Selection - SEPIC Regulator  
Equation 3 can be used to calculate the approximate inductor value for a SEPIC regulator:  
(
VOUT + VD  
TOFF  
L2 = 2  
(
ICL  
(3)  
The boost inductor, L1, can be smaller or larger but is generally chosen to be the same value as L2. See  
Figure 23 and Figure 24 for typical SEPIC applications.  
8.2.2.3 Diode Selection  
To maintain high efficiency, the average current rating of the Schottky diode should be larger than the peak  
inductor current, IPK. Schottky diodes with a low forward drop and fast switching speeds are ideal for increasing  
efficiency in portable applications. Choose a reverse breakdown of the Schottky diode larger than the output  
voltage.  
8.2.2.4 Capacitor Selection  
Choose low equivalent series resistance (ESR) capacitors for the output to minimize output voltage ripple.  
Multilayer ceramic capacitors are the best choice. For most applications, a 1-µF ceramic capacitor is sufficient.  
For some applications a reduction in output voltage ripple can be achieved by increasing the output capacitor.  
Output voltage ripple can further be reduced by adding a 4.7-pF feed-forward capacitor in the feedback network  
placed in parallel with RF1 (see Functional Block Diagram).  
Local bypassing for the input is needed on the LM2705. Multilayer ceramic capacitors are a good choice for this  
as well. A 4.7-µF capacitor is sufficient for most applications. For additional bypassing, a 100-nF ceramic  
capacitor can be used to shunt high frequency ripple on the input.  
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8.2.3 Application Curves  
Figure 13. Efficiency vs Load Current  
Figure 14. Efficiency vs Load Current  
Figure 15. Output Ripple Voltage  
Copt, Ropt Included  
Figure 16. Output Ripple Voltage  
Copt, Ropt Excluded  
Figure 17. Two White-LED Efficiency  
Figure 18. Three White-LED Efficiency  
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8.3 Additional Applications  
L
VIN  
2.5V-4.2V  
33 mH  
D
5
1
VIN  
SW  
COUT  
1 mF  
CIN  
4.7 mF  
Ceramic  
Ceramic  
LM2705  
>1.1 V  
4
SHDN  
0 V  
3
FB  
GND  
2
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Figure 19. Two White-LED Application  
L
VIN  
D
33 mH  
2.5 V - 4.2 V  
5
1
VIN  
SW  
CIN  
4.7 mF  
Ceramic  
COUT  
1 mF  
Ceramic  
LM2705  
>1.1 V  
4
SHDN  
0 V  
3
FB  
GND  
2
R2  
82 Ω  
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Figure 20. Three White-LED Application  
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Additional Applications (continued)  
L
VIN  
12 V  
8 mA  
D
33 µH  
2.5 V œ 4.2 V  
5
VIN  
1
SW  
R1  
240 kΩ  
LM2705  
CIN  
4.7 µF  
COUT  
1 µF  
4
SHDN  
3
FB  
R2  
27 kΩ  
GND  
2
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Figure 21. Li-Ion 12-V Application  
L
VIN  
5 V  
12 V  
18 mA  
D
33 µH  
5
1
VIN  
SW  
R1  
240 kΩ  
LM2705  
CIN  
4.7 µF  
COUT  
1 µF  
4
SHDN  
3
FB  
R2  
27 kΩ  
GND  
2
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Figure 22. 5-V to 12-V Application  
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Additional Applications (continued)  
CSEPIC  
1 µF  
L1  
22 µH  
VIN  
3.3 V  
30 mA  
D
2.5 V - 5.5 V  
1
SW  
5
VIN  
R1  
180 kΩ  
L2  
22 µH  
LM2705  
CIN  
4.7 µF  
COUT  
10 µF  
4
SHDN  
3
FB  
R2  
110 kΩ  
GND  
2
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Figure 23. 3.3-V SEPIC Application  
CSEPIC  
1 µF  
L1  
33 µH  
VIN  
2.5 V œ 7 V  
5 V  
20 mA  
D
1
5
VIN  
SW  
L2  
33 µH  
R1  
1 MΩ  
CIN  
4.7 µF  
COUT  
10 µF  
4
SHDN  
3
FB  
LM2705  
R2  
330 kΩ  
GND  
2
Copyright © 2016, Texas Instruments Incorporated  
Figure 24. 5-V SEPIC Application  
14  
Submit Documentation Feedback  
Copyright © 2002–2016, Texas Instruments Incorporated  
Product Folder Links: LM2705  
LM2705  
www.ti.com  
SNVS191F NOVEMBER 2002REVISED OCTOBER 2016  
9 Power Supply Recommendations  
The LM2705 is designed to operate from an input voltage supply range from 2.2 V to 7 V. This input supply must  
be well regulated and capable to supply the required input current. If the input supply is located far from the  
LM2705, additional bulk capacitance may be required in addition to the ceramic bypass capacitors.  
10 Layout  
10.1 Layout Guidelines  
The input bypass capacitor CIN, as shown in Figure 25, must be placed close to the device. This reduces copper  
trace resistance, which effects input voltage ripple of the LM2705 device. For additional input voltage filtering, a  
100-nF bypass capacitor can be placed in parallel with CIN to shunt any high frequency noise to ground. The  
output capacitor, COUT, must also be placed close to the device. Any copper trace connections for the COUT  
capacitor can increase the series resistance, which directly effects output voltage ripple. Keep the feedback  
network, resistors R1 and R2, close to the FB pin to minimize copper trace connections that can inject noise into  
the system. The ground connection for the feedback resistor network must connect directly to an analog ground  
plane. Tie the analog ground plane directly to the GND pin. If no analog ground plane is available, the ground  
connection for the feedback network must tie directly to the GND pin. Minimize trace connections made to the  
inductor and Schottky diode to reduce power dissipation and increase overall efficiency.  
10.2 Layout Example  
Inductor  
Schottky  
SW  
VIN  
CIN  
COUT  
LM2705  
GND  
FB  
SHDN  
R1  
R2  
Figure 25. LM2705 Layout Example  
Copyright © 2002–2016, Texas Instruments Incorporated  
Submit Documentation Feedback  
15  
Product Folder Links: LM2705  
 
LM2705  
SNVS191F NOVEMBER 2002REVISED OCTOBER 2016  
www.ti.com  
11 Device and Documentation Support  
11.1 Device Support  
11.1.1 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.  
11.2 Receiving Notification of Documentation Updates  
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper  
right corner, click on Alert me to register and receive a weekly digest of any product information that has  
changed. For change details, review the revision history included in any revised document.  
11.3 Community Resources  
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective  
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of  
Use.  
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration  
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help  
solve problems with fellow engineers.  
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and  
contact information for technical support.  
11.4 Trademarks  
E2E is a trademark of Texas Instruments.  
All other trademarks are the property of their respective owners.  
11.5 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.  
11.6 Glossary  
SLYZ022 TI Glossary.  
This glossary lists and explains terms, acronyms, and definitions.  
12 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.  
16  
Submit Documentation Feedback  
Copyright © 2002–2016, Texas Instruments Incorporated  
Product Folder Links: LM2705  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LM2705MF-ADJ/NOPB  
LM2705MFX-ADJ/NOPB  
ACTIVE  
ACTIVE  
SOT-23  
SOT-23  
DBV  
DBV  
5
5
1000 RoHS & Green  
3000 RoHS & Green  
SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
-40 to 85  
-40 to 85  
S59B  
S59B  
SN  
(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) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(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.  
(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 finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material 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 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
9-Aug-2022  
TAPE AND REEL INFORMATION  
REEL DIMENSIONS  
TAPE DIMENSIONS  
K0  
P1  
W
B0  
Reel  
Diameter  
Cavity  
A0  
A0 Dimension designed to accommodate the component width  
B0 Dimension designed to accommodate the component length  
K0 Dimension designed to accommodate the component thickness  
Overall width of the carrier tape  
W
P1 Pitch between successive cavity centers  
Reel Width (W1)  
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE  
Sprocket Holes  
Q1 Q2  
Q3 Q4  
Q1 Q2  
Q3 Q4  
User Direction of Feed  
Pocket Quadrants  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LM2705MF-ADJ/NOPB SOT-23  
LM2705MFX-ADJ/NOPB SOT-23  
DBV  
DBV  
5
5
1000  
3000  
178.0  
178.0  
8.4  
8.4  
3.2  
3.2  
3.2  
3.2  
1.4  
1.4  
4.0  
4.0  
8.0  
8.0  
Q3  
Q3  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
9-Aug-2022  
TAPE AND REEL BOX DIMENSIONS  
Width (mm)  
H
W
L
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LM2705MF-ADJ/NOPB  
LM2705MFX-ADJ/NOPB  
SOT-23  
SOT-23  
DBV  
DBV  
5
5
1000  
3000  
210.0  
210.0  
185.0  
185.0  
35.0  
35.0  
Pack Materials-Page 2  
PACKAGE OUTLINE  
DBV0005A  
SOT-23 - 1.45 mm max height  
S
C
A
L
E
4
.
0
0
0
SMALL OUTLINE TRANSISTOR  
C
3.0  
2.6  
0.1 C  
1.75  
1.45  
1.45  
0.90  
B
A
PIN 1  
INDEX AREA  
1
2
5
(0.1)  
2X 0.95  
1.9  
3.05  
2.75  
1.9  
(0.15)  
4
3
0.5  
5X  
0.3  
0.15  
0.00  
(1.1)  
TYP  
0.2  
C A B  
NOTE 5  
0.25  
GAGE PLANE  
0.22  
0.08  
TYP  
8
0
TYP  
0.6  
0.3  
TYP  
SEATING PLANE  
4214839/G 03/2023  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. Refernce JEDEC MO-178.  
4. Body dimensions do not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed 0.25 mm per side.  
5. Support pin may differ or may not be present.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
DBV0005A  
SOT-23 - 1.45 mm max height  
SMALL OUTLINE TRANSISTOR  
PKG  
5X (1.1)  
1
5
5X (0.6)  
SYMM  
(1.9)  
2
3
2X (0.95)  
4
(R0.05) TYP  
(2.6)  
LAND PATTERN EXAMPLE  
EXPOSED METAL SHOWN  
SCALE:15X  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
METAL  
EXPOSED METAL  
EXPOSED METAL  
0.07 MIN  
ARROUND  
0.07 MAX  
ARROUND  
NON SOLDER MASK  
DEFINED  
SOLDER MASK  
DEFINED  
(PREFERRED)  
SOLDER MASK DETAILS  
4214839/G 03/2023  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
DBV0005A  
SOT-23 - 1.45 mm max height  
SMALL OUTLINE TRANSISTOR  
PKG  
5X (1.1)  
1
5
5X (0.6)  
SYMM  
(1.9)  
2
3
2X(0.95)  
4
(R0.05) TYP  
(2.6)  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
SCALE:15X  
4214839/G 03/2023  
NOTES: (continued)  
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
9. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
IMPORTANT NOTICE AND DISCLAIMER  
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE  
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD  
PARTY INTELLECTUAL PROPERTY RIGHTS.  
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate  
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable  
standards, and any other safety, security, regulatory or other requirements.  
These resources are subject to change without notice. TI grants you permission to use these resources only for development of an  
application that uses the TI products described in the resource. Other reproduction and display of these resources is prohibited. No license  
is granted to any other TI intellectual property right or to any third party intellectual property right. TI disclaims responsibility for, and you  
will fully indemnify TI and its representatives against, any claims, damages, costs, losses, and liabilities arising out of your use of these  
resources.  
TI’s products are provided subject to TI’s Terms of Sale or other applicable terms available either on ti.com or provided in conjunction with  
such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable warranties or warranty disclaimers for  
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TI objects to and rejects any additional or different terms you may have proposed. IMPORTANT NOTICE  
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265  
Copyright © 2023, Texas Instruments Incorporated  

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