LM2771 [TI]
低纹波 250mA 开关电容器降压直流/直流转换器;
| 型号： | LM2771 |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | 低纹波 250mA 开关电容器降压直流/直流转换器 开关 电容器 转换器 |
| 文件： | 总16页 (文件大小：974K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LM2771
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SNVS435A –MARCH 2006–REVISED MAY 2013
LM2771 Low-Ripple 250mA Switched Capacitor Step-Down DC/DC Converter
Check for Samples: LM2771
1
FEATURES
DESCRIPTION
The LM2771 is a switched capacitor step-down
regulator that produces a 1.5V output without the use
of an inductor. It is capable of supplying loads up to
250mA. The LM2771 operates with an input voltage
from 2.7V to 5.5V, and requires only 3 low-cost
ceramic capacitors.
2
•
Low-Noise Fixed Frequency Operation
1.5V Output Voltage
•
•
•
•
•
•
•
•
•
•
•
Li-Ion (3.6V) to 1.5V with 81% Efficiency
1.7% Output Voltage Accuracy
Very Low Output Ripple: 8mV @ 250mA
Output Currents up to 250mA
The LM2771 uses a regulated 0.5x charge pump to
give power conversion efficiencies nearly twice as
high as an LDO. Pre-regulated 1.1MHz fixed-
frequency switching results in very low ripple and
noise on both the input and the output. When output
currents are low (<30mA typ.), the part automatically
switches to a low-ripple PFM regulation mode to
maintain high efficiency over the entire load range. At
input voltages below 3.5V (Typ), the charge pump
goes into pass mode, with efficiencies similar to an
LDO.
2.7V to 5.5V Input Range
Shutdown Disconnects Load from VIN
1.1MHz Switching Frequency
No Inductors…Small Solution Size
Current Limit and Thermal Protection
WSON-10 Package (3mm × 3mm × 0.8mm)
APPLICATIONS
•
DSP, Memory, and Microprocessor Power
Supplies
•
•
Mobile Phones and Pagers
Portable Electronic Devices
Typical Application Circuit
V
: 1.5V
OUT
V
IN
= 3.0V to 5.5V
I
up to 250 mA
OUT
V
V
OUT
IN
C
IN
1 mF
C
OUT
4.7mF
LM2771
C1+
C1-
GND
EN
Cfly
1 mF
Capacitors: 1 mF - TDK C1005X5R1A105K
4.7 mF - TDK C1608X5R0J475K
or equivalent
Figure 1.
Figure 2. LM2771 Efficiency vs.
Low-Dropout Linear Regulator (LDO) Efficiency
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.
2
All trademarks are the property of their respective owners.
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 © 2006–2013, Texas Instruments Incorporated
LM2771
SNVS435A –MARCH 2006–REVISED MAY 2013
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Connection Diagram
Figure 3. 10-Pin Non-Pullback Leadless Frame Package (WSON-10)
Package Number DSC0010A
1
2
3
4
5
10 EN
EN 10
1
2
3
4
5
V
V
IN
IN
GND
9
8
7
6
GND GND
9
GND
NC
C1+ C1+
C1- C1-
NC
8
7
6
V
V
OUT
OUT
NC
NC
NC
NC
Die-Attach
Pad: GND
Die-Attach
Pad: GND
Bottom View
Top View
Pin Descriptions
Pin #
Name
VIN
Description
1
2
Input Voltage: Recommended VIN operating range 3.0V to 5.5V.
GND
VOUT
NC
Ground
3
Output Voltage
4
No Connect
5
NC
No Connect
6
C1-
Flying Capacitor 1: Negative Terminal
Flying Capacitor 1: Positive Terminal
No Connect
7
C1+
NC
8
9
GND
EN
Ground
10
Enable Pin Logic Input. Applying a logic HIGH voltage signal enables the part. A logic LOW
voltage signal places the the device in shutdown.
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.
Absolute Maximum Ratings(1)(2)(3)
VIN Pin Voltage
-0.3V to 6.0V
EN Pin Voltage
-0.3V to (VIN+0.3V) w/ 6.0V max
Continuous Power Dissipation(4)
Internally Limited
150ºC
Junction Temperature (TJ-MAX
Storage Temperature Range
)
-65ºC to +150º C
265ºC
Maximum Lead Temperature(5)
Human Body Model
Machine Model
2.0kV
ESD Rating(6)
200V
(1) Absolute Maximum Ratings indicate limits beyond which damage to the component may occur. Operating Ratings are conditions under
which operation of the device is specified. Operating Ratings do not imply ensured performance limits. For specified performance limits
and associated test conditions, see the Electrical Characteristics tables.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) All voltages are with respect to the potential at the GND pins.
(4) Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at TJ=150ºC (typ.) and
disengages at TJ=140ºC (typ.).
(5) For detailed information on soldering requirements and recommendations, please refer to Texas Instruments' Application Note 1187
(Literature Number SNOA401): Leadless Leadframe Package (LLP).
(6) The Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF
capacitor discharged directly into each pin. MIL-STD-883 3015.7
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Operating Ratings(1)(2)
Input Voltage Range
2.7V to 5.5V
0mA to 250mA
-30°C to +110°C
-30°C to +85°C
Recommended Load Current Range
Junction Temperature (TJ) Range
Ambient Temperature (TA) Range(3)
(1) Absolute Maximum Ratings indicate limits beyond which damage to the component may occur. Operating Ratings are conditions under
which operation of the device is specified. Operating Ratings do not imply ensured performance limits. For specified performance limits
and associated test conditions, see the Electrical Characteristics tables.
(2) All voltages are with respect to the potential at the GND pins.
(3) Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-OP = 110ºC), the
maximum power dissipation of the device in the application (PD-MAX), and the junction-to ambient thermal resistance of the part/package
in the application (θJA), as given by the following equation: TA-MAX = TJ-MAX-OP – (θJA × PD-MAX).
Thermal Properties
Junction-to-Ambient Thermal Resistance (θJA), WSON-10 Package(1)
55°C/W
(1) Junction-to-ambient thermal resistance is highly application and board-layout dependent. In applications where high maximum power
dissipation exists, special care must be paid to thermal dissipation issues.
Electrical Characteristics(1)(2)
Limits in standard typeface are for TJ = 25ºC. Limits in boldface type apply over the full operating junction temperature range
(-30°C ≤ TJ ≤ +110°C) . Unless otherwise noted, specifications apply to the LM2771 Typical Application Circuit (pg. 1) with:
VIN = 3.6V; V(EN) = 1.8V, CIN = C1 = 1.0µF, COUT = 4.7µF.(3)
Symbol
Parameter
Condition
Min
Typ
Max
Units
3.0V ≤ VIN ≤ 5.5V
0mA ≤ IOUT ≤ 200mA
1.455
(−3%)
1.545
(+3%)
1.5
3.0V ≤ VIN ≤ 5.5V
IOUT = 150mA
1.475
(−1.7%)
1.525
(+1.7%)
VOUT
1.5V Output Voltage Regulation
1.5
1.5
V
3.0V < VIN ≤ 5.5V,
0mA ≤ IOUT ≤ 250mA
1.445
(−3.7%)
1.545
(+3%)
VOUT = 1.5V
0mA ≤ IOUT ≤ 250mA
VOUT/IOUT
Output Load Regulation
0.17
mV/mA
VOUT/VIN
E
Output Line Regulation
Power Efficiency
0.1
81
45
8
%/V
%
IOUT = 200mA
IOUT = 0mA(4)
IQ
Quiescent Supply Current
Fixed Frequency Output Ripple
PFM–Mode Output Ripple
Shutdown Current
50
µA
VR
40mA ≤ IOUT ≤ 250mA
IOUT < 40mA
mV
mV
µA
VR–PFM
ISD
12
0.1
1.1
1.0
V(EN) = 0V
0.5
FSW
ROL
Switching Frequency
3.2V ≤ VIN ≤ 5.5V
IOUT = 200mA(5)
0.80
1.40
MHz
Ω
Open–Loop Output Resistance
VIN = 5.5V
ICL
Output Current Limit
500
150
mA
0V ≤ VOUT ≤ 0.2V(6)
tON
VIL
VIH
IIH
Turn-on Time
µs
V
Logic-low Input Voltage
Logic-high Input Voltage
Logic-high Input Current
Logic-low Input Current
3.0V ≤ VIN ≤ 5.5V
3.0V ≤ VIN ≤ 5.5V
V(EN) = 1.8V(7)
Logic Input = 0V
0
0.5
VIN
0.95
V
5
µA
µA
IIL
0.1
(1) All voltages are with respect to the potential at the GND pins.
(2) Min and Max limits are specified by design, test, or statistical analysis. Typical numbers are not ensured, but do represent the most
likely norm.
(3) CIN, COUT, C1: Low-ESR Surface-Mount Ceramic Capacitors (MLCCs) used in setting electrical characteristics.
(4) VOUT is set to 1.6V during this test.
(5) Open loop output resistance can be used to predict output voltage when, under low VIN and high IOUT conditions, VOUT falls out of
regulation. VOUT = VIN/2 − (ROL × IOUT
)
(6) Maximum input current is equal to half the maximum output current for buck-mode switched capacitor converters.
(7) There is a 350kΩ pull-down resistor connected internally between the EN pin and GND.
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Block Diagram
LM2771
V
IN
1.3M
700k
C1+
C1-
SWITCH
ARRAY
GAIN
CONTROL
SWITCH
CONTROL
1
1,
1.25V
Ref.
G =
,
,
2
GND
V
OUT
Current
Sense
PFM
Control
1.1 MHz
OSC.
EN
Enable/
Shutdown
Control
EN
Soft-Start
Ramp
0.8V
Ref.
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Typical Performance Characteristics
Unless otherwise specified: VIN = 3.6V, CIN = C1 = 1.0µF, COUT = 4.7µF, TA = 25ºC. Capacitors are low-ESR multi-layer
ceramic capacitors (MLCC's).
Output Voltage
Output Voltage
vs.
vs.
Input Voltage
Output Current
Efficiency
vs.
Input Voltage
Efficiency
vs.
Output Current
Input Voltage Ripple, Load=6Ω(250mA)
Output Voltage Ripple, Load=6Ω(250mA)
CH1: VIN, CIN = 1µF; Scale: 50mV/Div, AC Coupled
CH2: VIN, CIN = 10µF; Scale: 50mV/Div, AC Coupled
Time scale: 200ns/Div
CH2: VOUT, COUT = 4.7µF; Scale: 20mV/Div, AC Coupled
Time scale: 200ns/Div
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Typical Performance Characteristics (continued)
Unless otherwise specified: VIN = 3.6V, CIN = C1 = 1.0µF, COUT = 4.7µF, TA = 25ºC. Capacitors are low-ESR multi-layer
ceramic capacitors (MLCC's).
Load Step, 15mA to 200mA
Load Step, 200mA to 15mA
CH2: VOUT; Scale: 20mV/Div, AC Coupled
CH4: IOUT; Scale: 200mA/Div
Time scale: 20µs/Div
CH2: VOUT; Scale: 20mV/Div, AC Coupled
CH4: IOUT; Scale: 200mA/Div
Time scale: 10µs/Div
Oscillator Frequency
vs.
Line Step, 3.6V to 4.5V with Load=7.5Ω(200mA)
Input Voltage
CH1: VIN; Scale: 1V/Div, AC Coupled
CH2: VOUT; Scale: 20mV/Div, AC Coupled
Time scale: 40µs/Div
Startup and Shutdown Behavior, Load=6Ω(250mA)
CH1: VEN; Scale: 2V/Div, DC Coupled
CH2: VOUT; Scale: 500mV/Div, DC Coupled
Time scale: 100µs/Div
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OPERATION DESCRIPTION
OVERVIEW
The LM2771 is a switched capacitor converter that produces a regulated, low voltage output. The core of the part
is a highly efficient charge pump that utilizes fixed frequency pre-regulation and Pulse Frequency Modulation to
minimize ripple and power losses over wide input voltage and output current ranges. A description of the
principal operational characteristics of the LM2771 is detailed in the CIRCUIT DESCRIPTION, and EFFICIENCY
PERFORMANCE sections. These sections refer to details in the Block Diagram.
CIRCUIT DESCRIPTION
The core of the LM2771 is a two-phase charge pump controlled by an internally generated non-overlapping
clock. The charge pump operates by using an external flying capacitor, C1, to transfer charge from the input to
the output. At input voltages below 3.5V (typ.) the LM2771 operates in a "pass mode", with the input current
being equal to the load current. At input voltages above 3.5V (typ.) the part utilizes a gain of ½, resulting in an
input current equal to half the load current.
The two phases of the switched capacitor switching cycle will be referred to as the "charge phase" and the
"discharge phase". During the charge phase, the flying capacitor is charged by the input supply. After half of the
switching cycle [ t = 1/(2×FSW) ], the LM2771 switches to the discharge phase. In this configuration, the charge
that was stored on the flying capacitor in the charge phase is transferred to the output.
The LM2771 uses fixed frequency pre-regulation to regulate the output voltage to 1.5V during moderate to high
load currents. The input and output connections of the flying capacitor is made with internal MOS switches. Pre-
regulation limits the gate drive of the MOS switch connected between the voltage input and the flying capacitor.
Controlling the on resistance of this switch limits the amount of charge transferred into and out of the flying
capacitor during the charge and discharge phases, and in turn helps to keep the output ripple very low.
When output currents are low (<30mA typ.), the LM2771 automatically switches to a low-ripple Pulse Frequency
Modulation (PFM) form of regulation. In PFM mode, the flying capacitor stays in the discharge phase until the
output voltage drops below a predetermined trip point. When this occurs, the flying capacitor switches back to the
charge phase. After being charged, the flying capacitor repeats the process of staying in the discharge phase
and switching to the charge phase when necessary.
EFFICIENCY PERFORMANCE
Charge-pump efficiency is derived in the following two ideal equations (supply current and other losses are
neglected for simplicity):
IIN = G × IOUT E = (VOUT × IOUT) ÷ (VIN × IIN) = VOUT ÷ (G × VIN)
(1)
In the equations, G represents the charge pump gain. Efficiency is at its highest as G×VIN approaches VOUT
.
Refer to the efficiency graph in the Typical Performance Characteristics section for detailed efficiency data. The
transition between Pass mode and the gain of ½ is clearly distinguished by the sharp discontinuity in the
efficiency curve.
SHUTDOWN
The LM2771 is in shutdown mode when the voltage on the enable pin (EN) is logic-low. In shutdown, the
LM2771 draws virtually no supply current. When in shutdown, the output of the LM2771 is completely
disconnected from the input. The internal feedback resistors will pull the output voltage down to 0V.
SOFT-START
The LM2771 employs soft start circuitry to prevent excessive input inrush currents during startup. At startup, the
output voltage gradually rises from 0V to the nominal output voltage. This occurs in 150µs (typ.). Soft-start is
engaged when the part is enabled, including situations where voltage is established simultaneously on the VIN
and EN pins.
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THERMAL SHUTDOWN
Protection from damage related to overheating is achieved with a thermal shutdown feature. When the junction
temperature rises to 150ºC (typ.), the part switches into shutdown mode. The LM2771 disengages thermal
shutdown when the junction temperature of the part is reduced to 140ºC (typ.). Due to the high efficiency of the
LM2771, thermal shutdown and/or thermal cycling should not be encountered when the part is operated within
specified input voltage, output current, and ambient temperature operating ratings. If thermal cycling is seen
under these conditions, the most likely cause is an inadequate PCB layout that does not allow heat to be
sufficiently dissipated out of the WSON package.
CURRENT LIMIT PROTECTION
The LM2771 charge pump contains current limit protection circuitry that protects the device during VOUT fault
conditions where excessive current is drawn. Output current is limited to 500mA (typ).
Application Information
RECOMMENDED CAPACITOR TYPES
The LM2771 requires 3 external capacitors for proper operation. Surface-mount multi-layer ceramic capacitors
are recommended. These capacitors are small, inexpensive and have very low equivalent series resistance
(ESR, ≤ 15mΩ typ.). Tantalum capacitors, OS-CON capacitors, and aluminum electrolytic capacitors generally
are not recommended for use with the LM2771 due to their high ESR, as compared to ceramic capacitors.
For most applications, ceramic capacitors with an X7R or X5R temperature characteristic are preferred for use
with the LM2771. These capacitors have tight capacitance tolerance (as good as ±10%) and hold their value over
temperature (X7R: ±15% over -55ºC to 125ºC; X5R: ±15% over -55ºC to 85ºC).
Capacitors with a Y5V or Z5U temperature characteristic are generally not recommended for use with the
LM2771. These types of capacitors typically have wide capacitance tolerance (+80%, -20%) and vary
significantly over temperature (Y5V: +22%, -82% over -30ºC to +85ºC range; Z5U: +22%, -56% over +10ºC to
+85ºC range). Under some conditions, a 1µF-rated Y5V or Z5U capacitor could have a capacitance as low as
0.1µF. Such detrimental deviation is likely to cause Y5V and Z5U capacitors to fail to meet the minimum
capacitance requirements of the LM2771.
Net capacitance of a ceramic capacitor decreases with increased DC bias. This degradation can result in lower
capacitance than expected on the input and/or output, resulting in higher ripple voltages and currents. Using
capacitors at DC bias voltages significantly below the capacitor voltage rating will usually minimize DC bias
effects. Consult capacitor manufacturers for information on capacitor DC bias characteristics.
Capacitance characteristics can vary quite dramatically with different application conditions, capacitor types, and
capacitor manufacturers. It is strongly recommended that the LM2771 circuit be thoroughly evaluated early in the
design-in process with the mass-production capacitors of choice. This will help ensure that any such variability in
capacitance does not negatively impact circuit performance.
The table below lists some leading ceramic capacitor manufacturers.
Manufacturer
AVX
Contact Information
www.avx.com
Murata
www.murata.com
www.t-yuden.com
www.component.tdk.com
www.vishay.com
Taiyo-Yuden
TDK
Vishay-Vitramon
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OUTPUT CAPACITOR AND OUTPUT VOLTAGE RIPPLE
The output capacitor in the LM2771 circuit (COUT) directly impacts the magnitude of output voltage ripple. Other
prominent factors also affecting output voltage ripple include input voltage, output current and flying capacitance.
Due to the complexity of the regulation topology, providing equations or models to approximate the magnitude of
the ripple can not be easily accomplished. But one important generalization can be made: increasing
(decreasing) the output capacitance will result in a proportional decrease (increase) in output voltage ripple.
In typical high-current applications, a 4.7µF low-ESR ceramic output capacitor is recommended. Different output
capacitance values can be used to reduce ripple, shrink the solution size, and/or cut the cost of the solution. But
changing the output capacitor may also require changing the flying capacitor and/or input capacitor to maintain
good overall circuit performance. Performance of the LM2771 with different capacitor setups in discussed in the
section RECOMMENDED CAPACITOR CONFIGURATIONS.
High ESR in the output capacitor increases output voltage ripple. If a ceramic capacitor is used at the output, this
is usually not a concern because the ESR of a ceramic capacitor is typically very low and has only a minimal
impact on ripple magnitudes. If a different capacitor type with higher ESR is used (tantalum, for example), the
ESR could result in high ripple. To eliminate this effect, the net output ESR can be significantly reduced by
placing a low-ESR ceramic capacitor in parallel with the primary output capacitor. The low ESR of the ceramic
capacitor will be in parallel with the higher ESR, resulting in a low net ESR based on the principles of parallel
resistance reduction.
INPUT CAPACITOR AND INPUT VOLTAGE RIPPLE
The input capacitor (CIN) is a reservoir of charge that aids a quick transfer of charge from the supply to the flying
capacitor during the charge phase of operation. The input capacitor helps to keep the input voltage from
drooping at the start of the charge phase when the flying capacitor is connected to the input. It also filters noise
on the input pin, keeping this noise out of sensitive internal analog circuitry that is biased off the input line.
Much like the relationship between the output capacitance and output voltage ripple, input capacitance has a
dominant and first-order effect on input ripple magnitude. Increasing (decreasing) the input capacitance will result
in a proportional decrease (increase) in input voltage ripple. Input voltage, output current, and flying capacitance
also will affect input ripple levels to some degree.
In typical high-current applications, a 1µF low-ESR ceramic capacitor is recommended on the input. Different
input capacitance values can be used to reduce ripple, shrink the solution size, and/or cut the cost of the
solution. But changing the input capacitor may also require changing the flying capacitor and/or output capacitor
to maintain good overall circuit performance. Performance of the LM2771 with different capacitor setups is
discussed below in RECOMMENDED CAPACITOR CONFIGURATIONS.
FLYING CAPACITOR
The flying capacitor (C1) transfers charge from the input to the output. Flying capacitance can impact both output
current capability and ripple magnitudes. If flying capacitance is too small, the LM2771 may not be able to
regulate the output voltage when load currents are high. On the other hand, if the flying capacitance is too large,
the flying capacitor might overwhelm the input and output capacitors, resulting in increased input and output
ripple.
Polarized capacitors (tantalum, aluminum electrolytic, etc.) must not be used for the flying capacitor, as they
could become reverse-biased during LM2771 operation.
RECOMMENDED CAPACITOR CONFIGURATIONS
The data in Table 1 can be used to assist in the selection of a capacitor configuration that best balances solution
size and cost with the electrical requirements of the application.
As previously discussed, input and output ripple voltages will vary with output current and input voltage. The
numbers provided show expected ripple voltage when VIN = 3.6V and load currents are between 10mA and
200mA. The table offers first look at approximate ripple levels and provides a comparison for the different
capacitor configurations presented, but is not intended to ensure performance.
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(1)
Table 1. LM2771 Performance with Different Capacitor Configurations
CAPACITOR
CONFIGURATION
(VIN = 3.6V)
TYPICAL
INPUT
RIPPLE
TYPICAL
OUTPUT
RIPPLE
CIN = 1µF,
COUT = 4.7µF,
C1 = 1µF
45mV
94mV
8mV
19mV
11mV
16mV
15mV
CIN = 1µF,
COUT = 2.2µF,
C1 = 1µF
CIN = 0.47µF,
COUT = 4.7µF,
C1 = 1µF
105mV
102mV
120mV
CIN = 0.47µF,
COUT = 3.3µF,
C1 = 1µF
CIN = 0.47µF,
COUT = 3.3µF,
C1 = 0.33µF
(1) Refer to the text in the Recommended Capacitor Configurations section for detailed information on the data in this table
Layout Guidelines
Proper board layout will help to ensure optimal performance of the LM2771 circuit. The following guidelines are
recommended:
•
•
Place capacitors as close to the LM2771 as possible, and preferably on the same side of the board as the IC.
Use short, wide traces to connect the external capacitors to the LM2771 to minimize trace resistance and
inductance.
•
Use a low resistance connection between ground and the GND pin of the LM2771. Using wide traces and/or
multiple vias to connect GND to a ground plane on the board is most advantageous.
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REVISION HISTORY
Changes from Original (May 2013) to Revision A
Page
•
Changed layout of National Data Sheet to TI format .......................................................................................................... 10
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PACKAGE OPTION ADDENDUM
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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)
LM2771SD/NOPB
ACTIVE
WSON
DSC
10
1000 RoHS & Green
SN
Level-1-260C-UNLIM
-30 to 110
L2771
(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
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Addendum-Page 1
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)
LM2771SD/NOPB
WSON
DSC
10
1000
178.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
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
WSON DSC 10
SPQ
Length (mm) Width (mm) Height (mm)
210.0 185.0 35.0
LM2771SD/NOPB
1000
Pack Materials-Page 2
MECHANICAL DATA
DSC0010A
SDA10A (Rev A)
www.ti.com
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相关型号：
LM2772SD/NOPB
IC SWITCHED CAPACITOR REGULATOR, 1500 kHz SWITCHING FREQ-MAX, DSO10, 3 X 3 MM, 0.80 MM HEIGHT, GREEN, LLP-10, Switching Regulator or Controller
NSC
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