LM2651MTCX-ADJ

更新时间:2024-09-18 19:09:35
品牌:TI
描述:2.6A SWITCHING REGULATOR, 345kHz SWITCHING FREQ-MAX, PDSO16, TSSOP-16

LM2651MTCX-ADJ 概述

2.6A SWITCHING REGULATOR, 345kHz SWITCHING FREQ-MAX, PDSO16, TSSOP-16 DC/DC转换器 开关式稳压器或控制器

LM2651MTCX-ADJ 规格参数

是否无铅: 含铅是否Rohs认证: 不符合
生命周期:Obsolete零件包装代码:TSSOP
包装说明:TSSOP, TSSOP16,.25针数:16
Reach Compliance Code:not_compliantECCN代码:EAR99
HTS代码:8542.39.00.01风险等级:5.11
模拟集成电路 - 其他类型:SWITCHING REGULATOR控制模式:CURRENT-MODE
控制技术:PULSE WIDTH MODULATION最大输入电压:14 V
最小输入电压:4 V标称输入电压:10 V
JESD-30 代码:R-PDSO-G16JESD-609代码:e0
长度:5 mm湿度敏感等级:1
功能数量:1端子数量:16
最高工作温度:125 °C最低工作温度:-40 °C
最大输出电流:2.6 A封装主体材料:PLASTIC/EPOXY
封装代码:TSSOP封装等效代码:TSSOP16,.25
封装形状:RECTANGULAR封装形式:SMALL OUTLINE, THIN PROFILE, SHRINK PITCH
峰值回流温度(摄氏度):260认证状态:Not Qualified
座面最大高度:1.2 mm子类别:Switching Regulator or Controllers
表面贴装:YES切换器配置:SINGLE
最大切换频率:345 kHz技术:CMOS
温度等级:AUTOMOTIVE端子面层:Tin/Lead (Sn/Pb)
端子形式:GULL WING端子节距:0.65 mm
端子位置:DUAL处于峰值回流温度下的最长时间:NOT SPECIFIED
宽度:4.4 mmBase Number Matches:1

LM2651MTCX-ADJ 数据手册

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LM2651  
www.ti.com  
SNVS032D FEBRUARY 2000REVISED APRIL 2013  
LM2651 1.5A High Efficiency Synchronous Switching Regulator  
Check for Samples: LM2651  
1
FEATURES  
DESCRIPTION  
The LM2651 switching regulator provides high  
efficiency power conversion over a 100:1 load range  
(1.5A to 15mA). This feature makes the LM2651 an  
ideal fit in battery-powered applications that demand  
long battery life in both run and standby modes.  
2
Ultra High Efficiency up to 97%  
High Efficiency Over a 1.5A to Milliamperes  
Load Range  
4V to 14V Input Voltage Range  
1.8V, 2.5V, 3.3V, or ADJ Output Voltage  
Synchronous rectification is used to achieve up to  
97% efficiency. At light loads, the LM2651 enters a  
low power hysteretic or “sleep” mode to keep the  
efficiency high. In many applications, the efficiency  
still exceeds 80% at 15mA load. A shutdown pin is  
available to disable the LM2651 and reduce the  
supply current to less than 10µA.  
Internal MOSFET Switch with Low RDS(on) of  
75m  
300kHz Fixed Frequency Internal Oscillator  
7µA Shutdown Current  
Patented Current Sensing for Current Mode  
Control  
The LM2651 contains a patented current sensing  
circuitry for current mode control. This feature  
eliminates the external current sensing resistor  
required by other current-mode DC-DC converters.  
Input Undervoltage Lockout  
Adjustable Soft-Start  
Current Limit and Thermal Shutdown  
16-pin TSSOP Package  
The LM2651 has a 300 kHz fixed frequency internal  
oscillator. The high oscillator frequency allows the  
use of extremely small, low profile components.  
APPLICATIONS  
A
programmable soft-start feature limits current  
Personal Digital Assistants (PDAs)  
Computer Peripherals  
surges from the input power supply at start up and  
provides a simple means of sequencing multiple  
power supplies.  
Battery-Powered Devices  
Handheld Scanners  
Other protection features include input undervoltage  
lockout, current limiting, and thermal shutdown.  
High Efficiency 5V Conversion  
Typical Application  
Figure 1. Efficiency vs Load Current  
(VIN = 5V, VOUT = 3.3V)  
Figure 2.  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
All trademarks are the property of their respective owners.  
2
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2000–2013, Texas Instruments Incorporated  
LM2651  
SNVS032D FEBRUARY 2000REVISED APRIL 2013  
www.ti.com  
Connection Diagram  
Figure 3. 16-Lead TSSOP  
See Package Number PW  
PIN DESCRIPTIONS  
Pin  
1, 2  
3-5  
6
Name  
SW  
Function  
Switched-node connection, which is connected with the source of the internal high-side MOSFET.  
Main power supply pin.  
VIN  
VCB  
Bootstrap capacitor connection for high-side gate drive.  
Input supply voltage for control and driver circuits.  
7
AVIN  
SD(SS)  
8
Shutdown and Soft-start control pin. Pulling this pin below 0.3V shuts off the regulator. A capacitor  
connected from this pin to ground provides a control ramp of the input current. Do not drive this pin  
with an external source or erroneous operation may result.  
9
FB  
Output voltage feedback input. Connected to the output voltage.  
10  
COMP  
NC  
Compensation network connection. Connected to the output of the voltage error amplifier.  
11  
No internal connection.  
Low-noise analog ground.  
Power ground.  
12-13  
14-16  
AGND  
PGND  
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.  
(1)(2)  
Absolute Maximum Ratings  
Input Voltage  
15V  
0.4V VFB 5V  
893 mW  
Feedback Pin Voltage  
Power Dissipation (TA =25°C),  
Junction Temperature Range  
Storage Temperature Range  
ESD Susceptibility  
(3)  
40°C TJ +125°C  
65°C to +150°C  
1kV  
(4)  
Human Body Model  
(1) Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating ratings indicate conditions for which  
the device is intended to be functional, but device parameter specifications may not be ensured under these conditions. For  
specifications and test conditions, see the Electrical Characteristics.  
(2) If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.  
(3) The maximum allowable power dissipation is calculated by using PDmax = (TJmax TA)/θJA , where TJmax is the maximum junction  
temperature, TA is the ambient temperature, and θJA is the junction-to-ambient thermal resistance of the specified package. The 893  
mW rating results from using 150°C, 25°C, and 140°C/W for TJmax, TA, and θJA respectively. A θJA of 140°C/W represents the worst-  
case condition of no heat sinking of the 16-pin TSSOP package. Heat sinking allows the safe dissipation of more power. The Absolute  
Maximum power dissipation must be derated by 7.14mW per °C above 25°C ambient. The LM2651 actively limits its junction  
temperature to about 165°C.  
(4) The human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin.  
2
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SNVS032D FEBRUARY 2000REVISED APRIL 2013  
(1)  
Operating Ratings  
Supply Voltage  
4V VIN 14V  
(1) Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating ratings indicate conditions for which  
the device is intended to be functional, but device parameter specifications may not be ensured under these conditions. For  
specifications and test conditions, see the Electrical Characteristics.  
LM2651-1.8 System Parameters  
Specifications in standard type face are for TJ = 25°C and those with boldface type apply over full operating junction  
temperature range. VIN =10V unless otherwise specified.  
Symbol  
VOUT  
Parameter  
Output Voltage  
Conditions  
ILOAD = 900 mA  
Typical  
Limit  
Units  
1.8  
1.761/1.719  
1.836/1.854  
V
V(min)  
V(max)  
VOUT  
VOUT  
VOUT  
VHYST  
Output Voltage Line Regulation  
VIN = 4V to 14V  
ILOAD = 900 mA  
0.2  
1.3  
0.3  
35  
%
Output Voltage Load Regulation ILOAD = 10 mA to 1.5A  
VIN = 5V  
%
Output Voltage Load Regulation ILOAD = 200 mA to 1.5A  
VIN = 5V  
%
Sleep Mode Output Voltage  
Hysteresis  
mV  
LM2651-2.5 System Parameters  
Symbol  
Parameter  
Conditions  
ILOAD = 900 mA  
Typical  
Limit  
Units  
VOUT  
Output Voltage  
2.5  
V
2.43/2.388  
2.574/2.575  
V(min)  
V(max)  
VOUT  
VOUT  
VOUT  
VHYST  
Output Voltage Line Regulation  
VIN = 4V to 12V  
ILOAD = 900 mA  
0.2  
1.3  
0.3  
48  
%
Output Voltage Load Regulation ILOAD = 10 mA to 1.5A  
VIN = 5V  
%
Output Voltage Load Regulation ILOAD = 200 mA to 1.5A  
VIN = 5V  
%
Sleep Mode Output Voltage  
Hysteresis  
mV  
LM2651-3.3 System Parameters  
Symbol  
Parameter  
Conditions  
ILOAD = 900 mA  
Typical  
Limit  
Units  
VOUT  
Output Voltage  
3.3  
V
3.265/3.201  
3.379/3.399  
V(min)  
V(max)  
VOUT  
VOUT  
VOUT  
VHYST  
Output Voltage Line Regulation  
VIN = 4V to 14V  
ILOAD = 900 mA  
0.2  
1.3  
0.3  
60  
%
Output Voltage Load Regulation ILOAD = 10 mA to 1.5A  
VIN = 5V  
%
Output Voltage Load Regulation ILOAD = 200 mA to 1.5A  
VIN = 5V  
%
Sleep Mode Output Voltage  
Hysteresis  
mV  
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SNVS032D FEBRUARY 2000REVISED APRIL 2013  
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Units  
LM2651-ADJ System Parameters  
(VOUT = 2.5V unless otherwise specified)  
Symbol  
VFB  
Parameter  
Feedback Voltage  
Conditions  
ILOAD = 900 mA  
Typical  
Limit  
1.238  
V
1.200  
1.263  
V(min)  
V(max)  
VOUT  
VOUT  
VOUT  
VHYST  
Output Voltage Line Regulation  
VIN = 4V to 14V  
ILOAD = 900 mA  
0.2  
1.3  
0.3  
24  
%
Output Voltage Load Regulation ILOAD = 10 mA to 1.5A  
VIN = 5V  
%
Output Voltage Load Regulation ILOAD = 200 mA to 1.5A  
VIN = 5V  
%
Sleep Mode Output Voltage  
Hysteresis  
mV  
All Output Voltage Versions  
Specifications in standard type face are for TJ = 25°C and those with boldface type apply over full operating junction  
temperature range. VIN =10V unless otherwise specified.  
Symbol  
Parameter  
Quiescent Current  
Conditions  
Typical  
Limit  
Units  
IQ  
1.6  
mA  
mA(max)  
2.0  
IQSD  
Quiescent Current in Shutdown  
Mode  
Shutdown Pin Pulled Low  
ISWITCH = 1A  
7
µA  
µA(max)  
12/20  
RSW(ON)  
High-Side or Low-Side Switch  
On Resistance (MOSFET On  
Resistance + Bonding Wire  
Resistance)  
110  
mΩ  
RDS(ON)  
IL  
MOSFET On Resistance (High-  
Side or Low-Side)  
ISWITCH = 1A  
75  
mΩ  
mΩ(max)  
130  
Switch Leakage Current - High  
Side  
130  
130  
6.75  
nA  
Switch Leakage Current - Low  
Side  
nA  
VBOOT  
Bootstrap Regulator Voltage  
IBOOT = 1 mA  
V
6.45/6.40  
6.95/7.00  
V(min)  
V(max)  
GM  
Error Amplifier  
Transconductance  
1250  
3.8  
210  
2
µmho  
VINUV  
VUV-HYST  
ICL  
VIN Undervoltage Lockout  
Threshold Voltage  
Rising Edge  
3.95  
V
V(max)  
Hysteresis for the Undervoltage  
Lockout  
mV  
Switch Current Limit  
VIN = 5V  
VIN = 5V  
A
1.55  
2.60  
A(min)  
A(max)  
ISM  
Sleep Mode Threshold Current  
Error Amplifier Voltage Gain  
Error Amplifier Source Current  
100  
100  
40  
mA  
V/V  
AV  
IEA_SOURCE  
µA  
25/15  
30  
µA(min)  
IEA_SINK  
VEAH  
VEAL  
VD  
Error Amplifier Sink Current  
65  
2.70  
1.25  
1
µA  
µA(min)  
Error Amplifier Output Swing  
Upper Limit  
V
2.50/2.40  
1.35/1.50  
V(min)  
Error Amplifier Output Swing  
Lower Limit  
V
V(max)  
Body Diode Voltage  
IDIODE = 1.5A  
V
4
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All Output Voltage Versions (continued)  
Specifications in standard type face are for TJ = 25°C and those with boldface type apply over full operating junction  
temperature range. VIN =10V unless otherwise specified.  
Symbol  
fOSC  
Parameter  
Conditions  
Typical  
Limit  
Units  
Oscillator Frequency  
VIN = 4V  
VIN = 4V  
300  
kHz  
kHz(min)  
kHz(max)  
280/255  
330/345  
DMAX  
ISS  
Maximum Duty Cycle  
Soft-Start Current  
95  
11  
%
%(min)  
92  
Voltage at the SS pin = 1.4V  
Shutdown Pin Pulled Low  
µA  
µA(min)  
µA(max)  
7
14  
ISHUTDOWN  
Shutdown Pin Current  
2.2  
0.6  
µA  
µA(min)  
µA(max)  
0.8/0.5  
3.7/4.0  
vSHUTDOWN  
Shutdown Pin Threshold Voltage Falling Edge  
Thermal Shutdown Temperature  
V
0.3  
0.9  
V(min)  
V(max)  
TSD  
165  
25  
°C  
TSD_HYST  
Thermal Shutdown Hysteresis  
Temperature  
°C  
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Typical Performance Characteristics  
IQ vs Input Voltage  
IQSD vs Input Voltage  
Figure 4.  
Figure 5.  
IQSD vs Junction Temperature  
Frequency vs Junction Temperature  
Figure 6.  
Figure 7.  
RDS(ON) vs Input Voltage  
RDS(ON) vs Junction Temperature  
Figure 8.  
Figure 9.  
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Typical Performance Characteristics (continued)  
Current Limit vs Input Voltage (VOUT =2.5V)  
Current Limit vs Junction Temperature (VOUT =2.5V)  
Figure 10.  
Current Limit vs Junction Temperature (VOUT = 3.3V)  
Figure 11.  
Current Limit vs Input Voltage (VOUT = 3.3V)  
Figure 12.  
Figure 13.  
Sleep Mode Threshold vs Output Voltage For ADJ version (VIN = 5V)  
Figure 14.  
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Figure 15. LM2651 Block Diagram  
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BLOCK DIAGRAM  
Operation  
The LM2651 operates in a constant frequency (300 kHz), current-mode PWM for moderate to heavy loads; and it  
automatically switches to hysteretic mode for light loads. In hysteretic mode, the switching frequency is reduced  
to keep the efficiency high.  
MAIN OPERATION  
When the load current is higher than the sleep mode threshold, the part is always operating in PWM mode. At  
the beginning of each switching cycle, the high-side switch is turned on, the current from the high-side switch is  
sensed and compared with the output of the error amplifier (COMP pin). When the sensed current reaches the  
COMP pin voltage level, the high-side switch is turned off; after 40 ns (deadtime), the low-side switch is turned  
on. At the end of the switching cycle, the low-side switch is turned off; and the same cycle repeats.  
The current of the top switch is sensed by a patented internal circuitry. This unique technique gets rid of the  
external sense resistor, saves cost and size, and improves noise immunity of the sensed current. A feedforward  
from the input voltage is added to reduce the variation of the current limit over the input voltage range.  
When the load current decreases below the sleep mode threshold, the output voltage will rise slightly, this rise is  
sensed by the hysteretic mode comparator which makes the part go into the hysteretic mode with both the high  
and low side switches off. The output voltage starts to drop until it hits the low threshold of the hysteretic  
comparator, and the part immediately goes back to the PWM operation. The output voltage keeps increasing  
until it reaches the top hysteretic threshold, then both the high and low side switches turn off again, and the  
same cycle repeats.  
PROTECTIONS  
The cycle-by-cycle current limit circuitry turns off the high-side MOSFET whenever the current in MOSFET  
reaches 2A.  
Design Procedure  
This section presents guidelines for selecting external components.  
INPUT CAPACITOR  
A low ESR aluminum, tantalum, or ceramic capacitor is needed betwen the input pin and power ground. This  
capacitor prevents large voltage transients from appearing at the input. The capacitor is selected based on the  
RMS current and voltage requirements. The RMS current is given by:  
(1)  
The RMS current reaches its maximum (IOUT/2) when VIN equals 2VOUT. For an aluminum or ceramic capacitor,  
the voltage rating should be at least 25% higher than the maximum input voltage. If a tantalum capacitor is used,  
the voltage rating required is about twice the maximum input voltage. The tantalum capacitor should be surge  
current tested by the manufacturer to prevent being shorted by the inrush current. It is also recommended to put  
a small ceramic capacitor (0.1 μF) between the input pin and ground pin to reduce high frequency spikes.  
INDUCTOR  
The most critical parameters for the inductor are the inductance, peak current and the DC resistance. The  
inductance is related to the peak-to-peak inductor ripple current, the input and the output voltages:  
(2)  
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A higher value of ripple current reduces inductance, but increases the conductance loss, core loss, current stress  
for the inductor and switch devices. It also requires a bigger output capacitor for the same output voltage ripple  
requirement. A reasonable value is setting the ripple current to be 30% of the DC output current. Since the ripple  
current increases with the input voltage, the maximum input voltage is always used to determine the inductance.  
The DC resistance of the inductor is a key parameter for the efficiency. Lower DC resistance is available with a  
bigger winding area. A good tradeoff between the efficiency and the core size is letting the inductor copper loss  
equal 2% of the output power.  
OUTPUT CAPACITOR  
The selection of COUT is driven by the maximum allowable output voltage ripple. The output ripple in the constant  
frequency, PWM mode is approximated by:  
(3)  
The ESR term usually plays the dominant role in determining the voltage ripple. A low ESR aluminum electrolytic  
or tantalum capacitor (such as Nichicon PL series, Sanyo OS-CON, Sprague 593D, 594D, AVX TPS, and CDE  
polymer aluminum) is recommended. An electrolytic capacitor is not recommended for temperatures below  
25°C since its ESR rises dramatically at cold temperature. A tantalum capacitor has a much better ESR  
specification at cold temperature and is preferred for low temperature applications.  
The output voltage ripple in constant frequency mode has to be less than the sleep mode voltage hysteresis to  
avoid entering the sleep mode at full load:  
VRIPPLE < 20mV x VOUT /VFB  
(4)  
BOOST CAPACITOR  
A 0.1 μF ceramic capacitor is recommended for the boost capacitor. The typical voltage across the boost  
capacitor is 6.7V.  
SOFT-START CAPACITOR  
A soft-start capacitor is used to provide the soft-start feature. When the input voltage is first applied, or when the  
SD(SS) pin is allowed to go high, the soft-start capacitor is charged by a current source (approximately 2 μA).  
When the SD(SS) pin voltage reaches 0.6V (shutdown threshold), the internal regulator circuitry starts to  
operate. The current charging the soft-start capacitor increases from 2 μA to approximately 10 μA. With the  
SD(SS) pin voltage between 0.6V and 1.3V, the level of the current limit is zero, which means the output voltage  
is still zero. When the SD(SS) pin voltage increases beyond 1.3V, the current limit starts to increase. The switch  
duty cycle, which is controlled by the level of the current limit, starts with narrow pulses and gradually gets wider.  
At the same time, the output voltage of the converter increases towards the nominal value, which brings down  
the output voltage of the error amplifier. When the output of the error amplifier is less than the current limit  
voltage, it takes over the control of the duty cycle. The converter enters the normal current-mode PWM  
operation. The SD(SS) pin voltage is eventually charged up to about 2V.  
The soft-start time can be estimated as:  
TSS = CSS x 0.6V/2 μA + CSS x (2V0.6V)/10 μA  
(5)  
R1 AND R2 (Programming Output Voltage)  
Use the following formula to select the appropriate resistor values:  
VOUT = VREF(1 + R1/R2)  
where  
VREF = 1.238V  
(6)  
Select resistors between 10kand 100k. (1% or higher accuracy metal film resistors for R1 and R2.)  
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COMPENSATION COMPONENTS  
In the control to output transfer function, the first pole Fp1 can be estimated as 1/(2πROUTCOUT); The ESR zero  
Fz1 of the output capacitor is 1/(2πESRCOUT); Also, there is a high frequency pole Fp2 in the range of 45kHz to  
150kHz:  
Fp2 = Fs/(πn(1D))  
where  
D = VOUT/VIN  
n = 1+0.348L/(VINVOUT) (L is in µHs and VIN and VOUT in volts).  
(7)  
The total loop gain G is approximately 500/IOUT where IOUT is in amperes.  
A Gm amplifier is used inside the LM2651. The output resistor Ro of the Gm amplifier is about 80k. Cc1 and RC  
together with Ro give a lag compensation to roll off the gain:  
Fpc1 = 1/(2πCc1(Ro+Rc)), Fzc1 = 1/2πCc1Rc.  
(8)  
In some applications, the ESR zero Fz1 cannot be cancelled by Fp2. Then, Cc2 is needed to introduce Fpc2 to  
cancel the ESR zero, Fp2 = 1/(2πCc2RoRc).  
The rule of thumb is to have more than 45° phase margin at the crossover frequency (G=1).  
If COUT is higher than 68µF, Cc1 = 2.2nF, and Rc = 15Kare good choices for most applications. If the ESR zero  
is too low to be cancelled by Fp2, add Cc2.  
If the transient response to a step load is important, choose RC to be higher than 10k.  
EXTERNAL SCHOTTKY DIODE  
A Schottky diode D1 is recommended to prevent the intrinsic body diode of the low-side MOSFET from  
conducting during the deadtime in PWM operation and hysteretic mode when both MOSFETs are off. If the body  
diode turns on, there is extra power dissipation in the body diode because of the reverse-recovery current and  
higher forward voltage; the high-side MOSFET also has more switching loss since the negative diode reverse-  
recovery current appears as the high-side MOSFET turn-on current in addition to the load current. These losses  
degrade the efficiency by 1-2%. The improved efficiency and noise immunity with the Schottky diode become  
more obvious with increasing input voltage and load current.  
The breakdown voltage rating of D1 is preferred to be 25% higher than the maximum input voltage. Since D1 is  
only on for a short period of time, the average current rating for D1 only requires being higher than 30% of the  
maximum output current. It is important to place D1 very close to the drain and source of the low-side MOSFET,  
extra parasitic inductance in the parallel loop will slow the turn-on of D1 and direct the current through the body  
diode of the low-side MOSFET.  
When an undervoltage situation occurs, the output voltage can be pulled below ground as the inductor current is  
reversed through the synchronous FET. For applications which need to be protected from a negative voltage, a  
clamping diode D2 is recommended. When used, D2 should be connected cathode to VOUT and anode to  
ground. A diode rated for a minimum of 2A is recommended.  
PCB Layout Considerations  
Layout is critical to reduce noises and ensure specified performance. The important guidelines are listed as  
follows:  
1. Minimize the parasitic inductance in the loop of input capacitors and the internal MOSFETs by connecting the  
input capacitors to VIN and PGND pins with short and wide traces. This is important because the rapidly  
switching current, together with wiring inductance can generate large voltage spikes that may result in noise  
problems.  
2. Minimize the trace from the center of the output resistor divider to the FB pin and keep it away from noise  
sources to avoid noise pick up. For applications requiring tight regulation at the output, a dedicated sense  
trace (separated from the power trace) is recommended to connect the top of the resistor divider to the  
output.  
3. If the Schottky diode D1 is used, minimize the traces connecting D1 to SW and PGND pins.  
Copyright © 2000–2013, Texas Instruments Incorporated  
Submit Documentation Feedback  
11  
Product Folder Links: LM2651  
 
LM2651  
SNVS032D FEBRUARY 2000REVISED APRIL 2013  
www.ti.com  
Figure 16. Schematic for the Typical Board Layout  
12  
Submit Documentation Feedback  
Copyright © 2000–2013, Texas Instruments Incorporated  
Product Folder Links: LM2651  
LM2651  
www.ti.com  
SNVS032D FEBRUARY 2000REVISED APRIL 2013  
REVISION HISTORY  
Changes from Revision C (April 2013) to Revision D  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 11  
Copyright © 2000–2013, Texas Instruments Incorporated  
Submit Documentation Feedback  
13  
Product Folder Links: LM2651  
PACKAGE OPTION ADDENDUM  
www.ti.com  
1-Nov-2013  
PACKAGING INFORMATION  
Orderable Device  
LM2651MTC-3.3  
Status Package Type Package Pins Package  
Eco Plan  
Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(6)  
(3)  
(4/5)  
NRND  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
PW  
16  
16  
16  
16  
16  
16  
92  
TBD  
Call TI  
CU SN  
Call TI  
CU SN  
CU SN  
CU SN  
Call TI  
2651MTC  
-3.3  
LM2651MTC-3.3/NOPB  
LM2651MTC-ADJ  
ACTIVE  
NRND  
PW  
PW  
PW  
PW  
PW  
92  
92  
Green (RoHS  
& no Sb/Br)  
Level-1-260C-UNLIM  
Call TI  
2651MTC  
-3.3  
TBD  
2651MTC  
-ADJ  
LM2651MTC-ADJ/NOPB  
LM2651MTCX-3.3/NOPB  
LM2651MTCX-ADJ/NOPB  
ACTIVE  
ACTIVE  
ACTIVE  
92  
Green (RoHS  
& no Sb/Br)  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
2651MTC  
-ADJ  
2500  
2500  
Green (RoHS  
& no Sb/Br)  
2651MTC  
-3.3  
Green (RoHS  
& no Sb/Br)  
2651MTC  
-ADJ  
(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.  
(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.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
1-Nov-2013  
(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  
23-Sep-2013  
TAPE AND REEL INFORMATION  
*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)  
LM2651MTCX-3.3/NOPB TSSOP  
LM2651MTCX-ADJ/NOPB TSSOP  
PW  
PW  
16  
16  
2500  
2500  
330.0  
330.0  
12.4  
12.4  
6.95  
6.95  
8.3  
8.3  
1.6  
1.6  
8.0  
8.0  
12.0  
12.0  
Q1  
Q1  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Sep-2013  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LM2651MTCX-3.3/NOPB  
LM2651MTCX-ADJ/NOPB  
TSSOP  
TSSOP  
PW  
PW  
16  
16  
2500  
2500  
367.0  
367.0  
367.0  
367.0  
35.0  
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  
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TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or  
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Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration  
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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.  
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Copyright © 2013, Texas Instruments Incorporated  

LM2651MTCX-ADJ CAD模型

  • 引脚图

  • 封装焊盘图

  • LM2651MTCX-ADJ 替代型号

    型号 制造商 描述 替代类型 文档
    LM2651MTCX-ADJ/NOPB TI 1.5A 高效开关稳压器 | PW | 16 | -40 to 125 完全替代
    LM2651MTC-ADJ/NOPB TI 1.5A 高效开关稳压器 | PW | 16 | -40 to 125 类似代替
    LM2651MTC-ADJ TI 1.5A 高效开关稳压器 | PW | 16 | -40 to 125 类似代替

    LM2651MTCX-ADJ 相关器件

    型号 制造商 描述 价格 文档
    LM2651MTCX-ADJ/NOPB NSC IC 2.6 A SWITCHING REGULATOR, 345 kHz SWITCHING FREQ-MAX, PDSO16, TSSOP-16, Switching Regulator or Controller 获取价格
    LM2651MTCX-ADJ/NOPB TI 1.5A 高效开关稳压器 | PW | 16 | -40 to 125 获取价格
    LM2651_05 NSC 1.5A High Efficiency Synchronous Switching Regulator 获取价格
    LM2652 NSC 1.5A, Dual High Performance Synchronous Buck Regulator 获取价格
    LM2652MTC NSC 1.5A, Dual High Performance Synchronous Buck Regulator 获取价格
    LM2653 NSC 1.5A High Efficiency Synchronous Switching Regulator 获取价格
    LM2653 TI 1.5A 高效同步开关稳压器 获取价格
    LM2653MTC-ADJ NSC 1.5A High Efficiency Synchronous Switching Regulator 获取价格
    LM2653MTC-ADJ TI LM2653 1.5A High Efficiency Synchronous Switching Regulator 获取价格
    LM2653MTC-ADJ/NOPB TI LM2653 1.5A High Efficiency Synchronous Switching Regulator 获取价格

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