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LM2750, LM2750-ADJ
SNVS180M – APRIL 2002 – REVISED JUNE 2015
LM2750 Low-Noise Switched-Capacitor Boost Regulator
1 Features
3 Description
•
•
The LM2750 is a regulated switched-capacitor
doubler that produces a low-noise output voltage. The
5-V output voltage option (LM2750-5.0) can supply up
to 120 mA of output current over a 2.9-V to 5.6-V
input range, as well as up to 40 mA of output current
when the input voltage is as low as 2.7 V. An
adjustable output voltage option with similar output
current capabilities is also available (LM2750-ADJ).
The LM2750 has been placed in TI's 10-pin WSON, a
package with excellent thermal properties that keeps
the part from overheating under almost all rated
operating conditions.
1
•
•
•
•
•
•
•
Wide Input Voltage Range: 2.7 V to 5.6 V
Inductorless Solution: Application Requires Only
Three Small Ceramic Capacitors
Fixed 5-V Output and Adjustable Output Voltage
Options Available
85% Peak Efficiency
– 70% Average Efficiency Over Li-Ion Input
Range (2.9 V to 4.2 V)
Output Current up to 120 mA With 2.9 V ≤ VIN ≤
5.6 V
– Output Current up to 40 mA With 2.7 V ≤ VIN ≤
2.9 V
Fixed 1.7-MHz Switching Frequency for a LowNoise, Low-Ripple Output Signal
Pre-Regulation Minimizes Input Current Ripple,
Keeping the Battery Line
(VIN) Virtually Noise-Free
Shutdown Supply Current Less Than 2 µA
Tiny WSON Package With Outstanding Power
Dissipation: Usually No Derating Required
A perfect fit for space-constrained, battery-powered
applications, the LM2750 requires only three external
components: one input capacitor, one output
capacitor, and one flying capacitor. Small,
inexpensive ceramic capacitors are recommended for
use. In conjunction with the
1.7-MHz fixed switching frequency of the LM2750,
these capacitors yield low output-voltage ripple, which
is beneficial for systems requiring a low-noise supply.
Pre-regulation minimizes input current ripple, thus
reducing input noise to negligible levels.
A tightly controlled soft-start feature limits inrush
currents during part activation. Shutdown completely
disconnects the load from the input. Output current
limiting and thermal shutdown circuitry protect both
the LM2750 and other connected devices in the event
of output shorts or excessive current loads.
2 Applications
•
•
•
•
White and Colored LED-Based Display Lighting
Cellular Phone SIM Cards
Audio Amplifier Power Supplies
General Purpose Li-Ion-to-5-V Conversion
Device Information(1)
PART NUMBER
LM2750
LM2750-ADJ
PACKAGE
WSON (10)
BODY SIZE (NOM)
3.00 mm × 3.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application Circuit
IOUT up to 120 mA, (VIN t 2.9 V)
IOUT up to 40 mA, (VIN t 2.7 V)
VIN
2.7 V to 5.6 V
8, 9
VOUT
VIN
CIN
2.2 PF
1, 2
COUT
2.2 PF
LM2750-5.0
4
CAP+
SD
VOUT
5 V ± 4%
10
CFLY
1 PF
CAPGND
7
3, 5, 6, DAP
Capacitors: 1 PF - TDK C1608X5R1A105K
2.2 PF - TDK C2012X7R1A225K
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.
LM2750, LM2750-ADJ
SNVS180M – APRIL 2002 – REVISED JUNE 2015
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
6.7
4
4
4
5
5
6
7
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Switching Characteristics ..........................................
Typical Characteristics ..............................................
Detailed Description .............................................. 9
7.1 Overview ................................................................... 9
7.2 Functional Block Diagram ......................................... 9
7.3 Feature Description................................................... 9
7.4 Device Functional Modes........................................ 12
8
Application and Implementation ........................ 13
8.1 Application Information............................................ 13
8.2 Typical Applications ............................................... 14
9
Power Supply Recommendations...................... 19
9.1 LED Driver Power Consumption ............................. 19
10 Layout................................................................... 20
10.1 Layout Recommendations .................................... 20
10.2 Layout Example .................................................... 20
11 Device and Documentation Support ................. 21
11.1
11.2
11.3
11.4
11.5
11.6
Device Support ....................................................
Documentation Support ........................................
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
21
21
21
21
21
21
12 Mechanical, Packaging, and Orderable
Information ........................................................... 22
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision L (May 2013) to Revision M
•
Page
Added Device Information and Pin Configuration and Functions sections, ESD Rating table, Feature Description,
Device Functional Modes, Application and Implementation, Power Supply Recommendations, Layout, Device and
Documentation Support, and Mechanical, Packaging, and Orderable Information sections; added already-released
LM2750-ADJ part number to title............................................................................................................................................ 1
Changes from Revision K (May 2013) to Revision L
•
2
Page
Changed layout of National Data Sheet to TI format ........................................................................................................... 19
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SNVS180M – APRIL 2002 – REVISED JUNE 2015
5 Pin Configuration and Functions
NGY or DSC Package
10-Pin WSON
VOUT
1
VOUT
2
GND/FB*
3
SD
4
GND
5
Die-Attach
Pad (DAP)
GND
VOUT
10
C+
C+
10
9
VIN
VIN
9
8
VIN
VIN
8
Die-Attach
Pad (DAP)
3
7
C-
C-
7
GND
4
SD
6
GND
GND
6
5
GND
Top View
1
2
VOUT
GND/FB*
Bottom View
* LM2750-5.0: Pin 3 = GND; LM2750-ADJ: Pin 3 = FB
Pin Names and Numbers apply to both NGY0010A and DSC0010A packages.
Pin Functions
PIN
TYPE
DESCRIPTION
NAME
LM2750-5.0
LM2750-ADJ
CAP+
10
10
P
Flying capacitor positive terminal
CAP–
7
7
P
Flying capacitor negative terminal
FB
—
3
P
Feedback pin
GND
3
G
This pin must be connected externally to the ground pins (pins 5, 6, and the
DAP).
GND
5, 6
5, 6
G
Ground - These pins must be connected externally.
SD
4
4
I/O
Active-Low Shutdown Input. A 200-kΩ resistor is connected internally between
this pin and GND to pull the voltage on this pin to 0 V, and shut the part down,
when the pin is left floating.
VIN
8, 9
8, 9
P
Input voltage - The pins must be connected externally.
VOUT
1, 2
1, 2
P
Output voltage - These pins must be connected externally.
√
√
GND
DAP
—
The DAP (Exposed Pad) functions as a thermal connection when soldered to a
copper plane.
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SNVS180M – APRIL 2002 – REVISED JUNE 2015
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6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1) (2)
MIN
MAX
UNIT
VIN pin: Voltage to Ground
–0.3
6
V
SD pin: Voltage to GND
–0.3
(VIN + 0.3)
V
150
°C
Junction temperature, TJ-MAX-ABS
Continuous power dissipation (3)
Maximum output current
Internally limited
(4)
Maximum lead temperature (Soldering, 5 sec.)
Storage temperature, Tstg
(1)
(2)
(3)
(4)
–65
175
mA
260
°C
150
°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.
Thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at TJ = 150°C (typical) and
disengages at TJ = 135°C (typical).
Absolute maximum output current specified by design. Recommended input voltage range for output currents in excess of 120 mA:
3.1 V to 4.4 V.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001
(1)
±2000
Machine model
±100
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted) (1) (2)
MIN
LM2750-5.0 input voltage
NOM
MAX
UNIT
2.7
5.6
V
3.8 V ≤ VOUT ≤ 4.9 V
2.7
(VOUT + 0.7)
V
4.9 V ≤ VOUT ≤ 5.2 V
2.7
5.6
V
3.8
5.2
V
2.9 V ≤ VIN ≤ 5.6 V
0
120
mA
2.7 V ≤ VIN ≤ 2.9 V
0
40
mA
Junction temperature (TJ)
–40
125
°C
Ambient temperature (TA) (3)
–40
85
°C
LM2750-ADJ input voltage
LM2750-ADJ output voltage
Recommended output current
(1)
(2)
(3)
4
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. For
performance limits and associated test conditions, see Electrical Characteristics.
All voltages are with respect to the potential at the GND pin.
Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-OP = 125ºC), 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 (RθJA), as given by this equation: TA-MAX = TJ-MAX-OP – (RθJA × PD-MAX). Maximum power dissipation of the LM2750 in a
given application can be approximated using this equation: PD-MAX = (VIN-MAX × IIN-MAX) – (VOUT × IOUT-MAX) = [VIN-MAX × ((2 × IOUT-MAX) +
5 mA)] - (VOUT × IOUT-MAX). In this equation, VIN-MAX, IIN-MAX, and IOUT-MAX are the maximum voltage/current of the specific application,
and not necessarily the maximum rating of the LM2750. The maximum ambient temperature rating of 85ºC is determined under the
following application conditions: RθJA = 55ºC/W, PD-MAX = 727 mW (achieved when VIN-MAX = 5.5 V and IOUT-MAX = 115 mA, for
example). Maximum ambient temperature must be derated by 1.1ºC for every increase in internal power dissipation of 20 mW above
727 mW (again assuming that RθJA = 55ºC/W in the application). For more information on these topics, see TI's AN-1187 Leadless
Leadframe Package (LLP) (SNOA401) and Power Efficiency And Power Dissipation.
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6.4 Thermal Information
LM2750-5.0, LM2750-ADJ
THERMAL METRIC (1)
RθJA
(1)
NGY (WSON)
DSC (WSON)
10 PINS
10 PINS
55
55
Junction-to-ambient thermal resistance
UNIT
°C/W
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report. SPRA953.
6.5 Electrical Characteristics
Typical values apply for TJ = 25°C; minimum and maximum limits apply over the operating junction temperature range; 2.9 V
≤ VIN ≤ 5.6 V, VOUT = 5 V (LM2750-ADJ), V(SD) = VIN, CFLY = 1 µF, CIN = 2 × 1 µF, COUT = 2 × 1 µF, unless otherwise specified
(1) (2) (3)
.
PARAMETER
VOUT
IQ
Output voltage
(LM2750-5.0)
Operating supply current
MIN
TYP
MAX
2.9 V ≤ VIN ≤ 5.6 V,
IOUT ≤ 120 mA
TEST CONDITIONS
4.8 (–4%)
5
5.2 (4%)
2.7 V ≤ VIN ≤ 2.9 V,
IOUT ≤ 40 mA, TJ = 25°C
4.8 (–4%)
5
5.2 (4%)
5
10
UNIT
V
IOUT = 0mA, TJ = 25°C
VIH(MIN) ≤ V(SD) ≤ VIN
mA
IOUT = 0 mA,
VIH(MIN) ≤ V(SD) ≤ VIN
12
ISD
Shutdown supply current
V(SD) = 0V
VFB
Feedback pin voltage
(LM2750-ADJ)
VIN = 3.1 V
IFB
Feedback pin input current
(LM2750-ADJ)
VFB = 1.4 V
1
VR
Output ripple
COUT = 10 µF, IOUT = 100 mA
4
COUT = 2.2 µF, IOUT = 100 mA
15
EPEAK
Peak efficiency
(LM2750-5.0)
VIN = 2.7 V, IOUT = 40 mA
87%
VIN = 2.9 V, IOUT = 120 mA
85%
VIN = 2.9 V to 4.2 V, IOUT = 120 mA
70%
EAVG
Average Efficiency over Li-Ion
Input Range
(LM2750-5.0) (4)
VIN = 2.9 V to 4.2 V, IOUT = 40 mA
67%
ƒSW
Switching frequency
ILIM
Current limit
1.17
1
VOUT shorted to GND
1.232
2
µA
1.294
V
nA
mVp-p
1.7
MHz
300
mA
SHUTDOWN PIN (SD) CHARACTERISTICS
VIH
Logic-high SD input
VIL
Logic-low SD input
IIH
SD input current
IIL
SD input current
(1)
(2)
(3)
(4)
(5)
(5)
1.3
VIN
V
0
0.4
V
50
µA
1
µA
1.3 V ≤ V(SD) ≤ VIN
V(SD) = 0 V
15
–1
All voltages are with respect to the potential at the GND pin.
Minimum and maximum limits are specified by design, test, or statistical analysis. Typical numbers represent the most likely norm.
CFLY, CIN, and COUT : Low-ESR Surface-Mount Ceramic Capacitors (MLCCs) used in setting electrical characteristics
Efficiency is measured versus VIN, with VIN being swept in small increments from 3 V to 4.2 V. The average is calculated from these
measurements results. Weighting to account for battery voltage discharge characteristics (VBAT vs. time) is not done in computing the
average.
SD Input Current (IIH ) is due to a 200-kΩ (typical) pulldown resistor connected internally between the SD pin and GND.
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Electrical Characteristics (continued)
Typical values apply for TJ = 25°C; minimum and maximum limits apply over the operating junction temperature range; 2.9 V
≤ VIN ≤ 5.6 V, VOUT = 5 V (LM2750-ADJ), V(SD) = VIN, CFLY = 1 µF, CIN = 2 × 1 µF, COUT = 2 × 1 µF, unless otherwise specified
(1)(2)(3)
.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
CAPACITOR CHARACTERISTICS
CIN
Required input capacitance (6)
COUT
Required output capacitance (6)
(6)
IOUT ≤ 60 mA
1
60 mA ≤ IOUT ≤ 120 mA
2
IOUT ≤ 60 mA
1
60 mA ≤ IOUT ≤ 120 mA
2
µF
µF
Limit is the minimum required output capacitance to ensure proper operation. This electrical specification is specified by design.
6.6 Switching Characteristics
over operating free-air temperature range (unless otherwise noted)
PARAMETER
tON
(1)
6
VOUT turnon time
TEST CONDITIONS
MIN
VIN = 3 V, IOUT = 100 mA (1)
TYP
0.5
MAX
UNIT
ms
Turnon time is measured from when SD signal is pulled high until the output voltage crosses 90% of its final value.
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6.7 Typical Characteristics
Unless otherwise specified: VIN = 3.6 V, TA = 25°C, CIN = 2.2 µF, CFLY = 1 µF, COUT = 2.2 µF. Capacitors are low-ESR multilayer ceramic capacitors (MLCCs).
Figure 1. Output Voltage vs. Output Current
Figure 2. Output Voltage vs. Output Current
Figure 3. Output Voltage vs. Input Voltage
Figure 4. Input Current vs. Output Current
Figure 5. Quiescent Supply Current
Figure 6. Current Limit Behavior
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Typical Characteristics (continued)
Unless otherwise specified: VIN = 3.6 V, TA = 25°C, CIN = 2.2 µF, CFLY = 1 µF, COUT = 2.2 µF. Capacitors are low-ESR multilayer ceramic capacitors (MLCCs).
Figure 7. Switching Frequency
Figure 8. Output Voltage Ripple
IOUT = 120 mA
Figure 9. Output Voltage Ripple
8
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Figure 10. Turnon Behavior
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7 Detailed Description
7.1 Overview
The LM2750 is a regulated switched capacitor doubler that, by combining the principles of switched-capacitor
voltage boost and linear regulation, generates a regulated output from an extended Li-Ion input voltage range. A
two-phase non-overlapping clock generated internally controls the operation of the doubler. During the charge
phase (φ1), the flying capacitor (CFLY) is connected between the input and ground through internal passtransistor switches and is charged to the input voltage. In the pump phase that follows (φ2), the flying capacitor is
connected between the input and output through similar switches. Stacked atop the input, the charge of the flying
capacitor boosts the output voltage and supplies the load current.
A traditional switched capacitor doubler operating in this manner uses switches with very low on-resistance to
generate an output voltage that is 2× the input voltage. The LM2750 regulates the output voltage by controlling
the resistance of the two input-connected pass-transistor switches in the doubler.
7.2 Functional Block Diagram
C-
C+
LM2750
S1
I1
S3
I2
S2
I1
S4
I2
VOUT
OCL
OCL = Overcurrent Limit
Ra*
VIN
R1**
FB**
1.7-MHz
Osc.
Rb*
SD
Softstart
R2**
1.2-V
Ref.
GND
* LM2750-5.0 only
** LM2750-ADJ only
7.3 Feature Description
7.3.1 Pre-Regulation
The very low input current ripple of the LM2750, which results from internal pre-regulation, adds very little noise
to the input line. The core of the LM2750 is very similar to that of a basic switched capacitor doubler: it is
composed of four switches and a flying capacitor (external). Regulation is achieved by modulating the onresistance of the two switches connected to the input pin (one switch in each phase). The regulation is done
before the voltage doubling, giving rise to the term pre-regulation. It is pre-regulation that eliminates most of the
input current ripple that is a typical and undesirable characteristic of a many switched capacitor converters.
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Feature Description (continued)
7.3.2 Input, Output, And Ground Connections
Making good input, output, and ground connections is essential to achieve optimal LM2750 performance. The
two input pads, pads 8 and 9, must be connected externally. It is strongly recommended that the input capacitor
(CIN) be placed as close as possible to the LM2750, so that the traces from the input pads are as short and
straight as possible. To minimize the effect of input noise on LM2750 performance, it is best to bring two traces
out from the LM2750 all the way to the input capacitor pad, so that they are connected at the capacitor pad.
Connecting the two input traces between the input capacitor and the LM2750 input pads could make the LM2750
more susceptible to noise-related performance degradation. It is also recommended that the input capacitor be
on the same side of the PCB as the LM2750, and that traces remain on this side of the board as well (vias to
traces on other PCB layers are not recommended between the input capacitor and LM2750 input pads).
The two output pads, pads 1 and 2, must also be connected externally. It is recommended that the output
capacitor (COUT) be placed as close to the LM2750 output pads as possible. It is best if routing of output pad
traces follow guidelines similar to those presented for the input pads and capacitor. The flying capacitor (CFLY)
must also be placed as close to the LM2750 as possible to minimize PCB trace length between the capacitor and
the IC. Due to the pad-layout of the part, it is likely that the trace from one of the flying capacitor pads (C+ or C–)
needs to be routed to an internal or opposite-side layer using vias. This is acceptable, and it is much more
advantageous to route a flying capacitor trace in this fashion than it is to place input traces on other layers.
The GND pads of the LM2750 are ground connections and must be connected externally. These include pads 3
(LM2750-5.0 only), 5, 6, and the die-attach pad (DAP). Large, low impedance copper fills and via connections to
an internal ground plane are the preferred way of connecting together the ground pads of the LM2750, the input
capacitor, and the output capacitor, as well as connecting this circuit ground to the system ground of the PCB.
7.3.3 Shutdown
When the voltage on the active-low-logic shutdown pin is low, the LM2750 is in shutdown mode. In shutdown,
the LM2750 draws virtually no supply current. There is a 200-kΩ pulldown resistor tied between the SD pin and
GND that pulls the SD pin voltage low if the pin is not driven by a voltage source. When pulling the part out of
shutdown, the voltage source connected to the SD pin must be able to drive the current required by the 200-kΩ
resistor. For voltage management purposes required upon start-up, internal switches connect the output of the
LM2750 to an internal pulldown resistor (1 kΩ typical) when the part is shut down. Driving the output of the
LM2750 by another supply when the LM2750 is shut down is not recommended, as the pulldown resistor was not
sized to sink continuous current.
7.3.4 Soft Start
The LM2750 employs soft start circuitry to prevent excessive input inrush currents during start-up. The output
voltage is programmed to rise from 0 V to the nominal output voltage (5 V) in 500 µs (typical). Soft-start is
engaged when a part, with input voltage established, is taken out of shutdown mode by pulling the SD pin
voltage high. Soft-start also engages when voltage is established simultaneously to the input and SD pins.
7.3.5 Output Current Capability
The LM2750-5.0 provides 120 mA of output current when the input voltage is within 2.9 V to 5.6 V. Using the
LM2750 to drive loads in excess of 120 mA is possible.
NOTE
Understanding relevant application issues is recommended and a thorough analysis of the
application circuit must be performed when using the part outside operating ratings and/or
specifications to ensure satisfactory circuit performance in the application. Special care
must be paid to power dissipation and thermal effects. These parameters can have a
dramatic impact on high-current applications, especially when the input voltage is high.
(see Power Efficiency And Power Dissipation).
10
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Feature Description (continued)
The schematic of Figure 11 is a simplified model of the LM2750 that is useful for evaluating output current
capability. The model shows a linear pre-regulation block (Reg), a voltage doubler (2×), and an output resistance
(ROUT). Output resistance models the output voltage droop that is inherent to switched capacitor converters. The
output resistance of the LM2750 is 5 Ω (typical), and is approximately equal to twice the resistance of the four
LM2750 switches. When the output voltage is in regulation, the regulator in the model controls the voltage V' to
keep the output voltage equal to 5 V ± 4%. With increased output current, the voltage drop across ROUT
increases. To prevent droop in output voltage, the voltage drop across the regulator is reduced, V' increases, and
VOUT remains at 5V. When the output current increases to the point that there is zero voltage drop across the
regulator, V' equals the input voltage, and the output voltage is "on the edge" of regulation. Additional output
current causes the output voltage to fall out of regulation, and the LM2750 operation is similar to a basic openloop doubler. As in a voltage doubler, increase in output current results in output voltage drop proportional to the
output resistance of the doubler. The out-of-regulation LM2750 output voltage can be approximated by:
8176 = 2 ×8+0 F +176 × 4176
(1)
Again, Equation 1 only applies at low input voltage and high output current where the LM2750 is not regulating.
See Figure 1 and Figure 2 in for more details.
LM2750
VIN
Reg
V'
2×
VOUT
2×V '
ROUT
Figure 11. LM2750 Output Resistance Model
A more complete calculation of output resistance takes into account the effects of switching frequency, flying
capacitance, and capacitor equivalent series resistance (ESR). See Equation 2:
4176 = 2 × 459 +
1
+ 4 × '54%(.; + '54%176
(59 × %(.;
(2)
Switch resistance (5 Ω typical) dominates the output resistance equation of the LM2750. With a 1.7-MHz typical
switching frequency, the 1/(F×C) component of the output resistance contributes only 0.6 Ω to the total output
resistance. Increasing the flying capacitance only provides minimal improvement to the total output current
capability of the LM2750. In some applications it may be desirable to reduce the value of the flying capacitor
below 1 µF to reduce solution size and/or cost, but this must be done with care so that output resistance does
not increase to the point that undesired output voltage droop results. If ceramic capacitors are used, equivalent
series resistance (ESR) is a negligible factor in the total output resistance, as the ESR of quality ceramic
capacitors is typically much less than 100 mΩ.
7.3.6 Thermal Shutdown
The LM2750 implements a thermal shutdown mechanism to protect the device from damage due to overheating.
When the junction temperature rises to 150°C (typical), the part switches into shutdown mode. The LM2750
releases thermal shutdown when the junction temperature of the part is reduced to 130°C (typical).
Thermal shutdown is most-often triggered by self-heating, which occurs when there is excessive power
dissipation in the device and/or insufficient thermal dissipation. LM2750 power dissipation increases with
increased output current and input voltage (see Power Efficiency And Power Dissipation). When self-heating
brings on thermal shutdown, thermal cycling is the typical result. Thermal cycling is the repeating process where
the part self-heats, enters thermal shutdown (where internal power dissipation is practically zero), cools, turns on,
and then heats up again to the thermal shutdown threshold. Thermal cycling is recognized by a pulsing output
voltage and can be stopped be reducing the internal power dissipation (reduce input voltage and/or output
current) or the ambient temperature. If thermal cycling occurs under desired operating conditions, thermal
dissipation performance must be improved to accommodate the power dissipation of the LM2750. The WSON
package has excellent thermal properties that, when soldered to a PCB designed to aid thermal dissipation,
allows the LM2750 to operate under very demanding power dissipation conditions.
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Feature Description (continued)
7.3.7 Output Current Limiting
The LM2750 contains current limit circuitry that protects the device in the event of excessive output current
and/or output shorts to ground. Current is limited to 300 mA (typ.) when the output is shorted directly to ground.
When the LM2750 is current limiting, power dissipation in the device is likely to be quite high. In this event,
thermal cycling must be expected (see Thermal Shutdown).
7.3.8 Programming the Output Voltage of the LM2750-ADJ
As shown in Figure 12, the output voltage of the LM2750-ADJ can be programmed with a simple resistor divider
(see resistors R1 and R2). The values of the feedback resistors set the output voltage, as determined by:
VOUT = 1.23 V × (1 + R1/ R2).
In the previous equation, 1.23 V is the nominal voltage of the feedback pin when the feedback loop is correctly
established, and the part is operating normally. The sum of the resistance of the two feedback resistors must be
between 15 kΩ and 20 kΩ: 15 kΩ < (R1 + R2) < 20 kΩ.
If larger feedback resistors are desired, a 10-pF capacitor must be placed in parallel with resistor R1.
7.4 Device Functional Modes
7.4.1 PWM Brightness/Dimming Control
Brightness of the LEDs can be adjusted in an application by driving the SD pin of the LM2750 with a PWM
signal. When the PWM signal is high, the LM2750 is ON, and current flows through the LEDs, as described in
the previous section. A low PWM signal turns the part and the LEDs OFF. The perceived brightness of the LEDs
is proportional to ON current of the LEDs and the duty cycle (D) of the PWM signal (the percentage of time the
LEDs are ON).
To achieve good brightness/dimming control with this circuit, proper selection of the PWM frequency is required.
The PWM frequency (ƒPWM) must be set higher than 100 Hz to avoid visible flickering of the LED light. An upper
bound on this frequency is also needed to accommodate the turn-on time of the LM2750 (TON = 0.5 ms typical).
This maximum recommended PWM frequency is similarly dependent on the minimum duty cycle (DMIN) of the
application. The next equation puts bounds on the recommended PWM frequency range:
100 Hz < FPWM < DMIN ÷ TON.
Choosing a PWM frequency within these limits results in fairly linear control of the time-averaged LED current
over the full duty-cycle adjustment range. For most applications, a PWM frequency between 100 Hz and 500 Hz
is recommended. A PWM frequency up to 1 kHz may be acceptable in some designs.
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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 must
validate and test their design implementation to confirm system functionality.
8.1 Application Information
8.1.1 Output Voltage Ripple
The amount of voltage ripple on the output of the LM2750 is highly dependent on the application conditions:
output current and the output capacitor, specifically. A simple approximation of output ripple is determined by
calculating the amount of voltage droop that occurs when the output of the LM2750 is not being driven. This
occurs during the charge phase (φ1). During this time, the load is driven solely by the charge on the output
capacitor. The magnitude of the ripple thus follows the basic discharge equation for a capacitor (I = C × dV/dt),
where discharge time is one-half the switching period, or 0.5/FSW. Put simply,
4+22.'2A=G F2A=G =
+176
0.5
×
(59
%176
(3)
A more thorough and accurate examination of factors that affect ripple requires including effects of phase nonoverlap times and output capacitor equivalent series resistance (ESR). In order for the LM2750 to operate
properly, the two phases of operation must never coincide. (If this were to happen all switches would be closed
simultaneously, shorting input, output, and ground). Thus, non-overlap time is built into the clocks that control the
phases. Since the output is not being driven during the non-overlap time, this time must be accounted for in
calculating ripple. Actual output capacitor discharge time is approximately 60% of a switching period, or 0.6/FSW.
The ESR of the output capacitor also contributes to the output voltage ripple, as there is effectively an AC
voltage drop across the ESR due to current switching in and out of the capacitor. Equation 4 is a more complete
calculation of output ripple than presented previously, taking into account phase non-overlap time and capacitor
ESR.
4+22.'2A=G F2A=G =
+176
0.6
×
+ (2 × +176 × '54%176
%176 (59
(4)
A low-ESR ceramic capacitor is recommended on the output to keep output voltage ripple low. Placing multiple
capacitors in parallel can reduce ripple significantly, both by increasing capacitance and reducing ESR. When
capacitors are in parallel, ESR is in parallel as well. The effective net ESR is determined according to the
properties of parallel resistance. Two identical capacitors in parallel have twice the capacitance and half the ESR
as compared to a single capacitor of the same make. On a similar note, if a large-value, high-ESR capacitor
(tantalum, for example) is to be used as the primary output capacitor, the net output ESR can be significantly
reduced by placing a low-ESR ceramic capacitor in parallel with this primary output capacitor.
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8.2 Typical Applications
8.2.1 LM2750-ADJ Typical Application
VIN
2.7 V to 5.6 V
8, 9
CIN
2.2 PF
For VOUT < 4.9 V:
max VIN= VOUT + 0.7 V
1, 2
VIN
VOUT = 1.23 V × (1 + R1/R2)
VOUT Range: 3.8 V to 5.2 V
IOUT up to 120 mA
VOUT
COUT
2.2 PF
LM2750-ADJ
R1
10
CFLY
1 PF
3
CAP+
FB
4
7
R2
SD
CAPGND
5, 6, DAP
Capacitors: 1 PF - TDK C1608X5R1A105K
2.2 PF - TDK C2012X7R1A225K
Figure 12. LM2750-ADJ Typical Application Circuit
8.2.1.1 Design Requirements
Example requirements for LM2750-ADJ:
DESIGN PARAMETER
EXAMPLE VALUE
Input voltage range
2.7 V to 5.6 V
Output current, 2.9 V ≤ 5.6 V
up to 120 mA
Output current, 2.7 V ≤ 2.9 V
up to 40 mA
Switching frequency
1.7 MHz
8.2.1.2 Detailed Design Procedure
8.2.1.2.1 Capacitors
The LM2750 requires three 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 (≤ 10 mΩ typical). Tantalum capacitors, OS-CON capacitors, and aluminum electrolytic capacitors
generally are not recommended for use with the LM2750 due to their high ESR, as compared to ceramic
capacitors.
For most applications, ceramic capacitors with X7R or X5R temperature characteristic are preferred for use with
the LM2750. These capacitors have tight capacitance tolerance (as good as ±10%), hold their value over
temperature (X7R: ±15% over –55°C to 125°C; X5R: ±15% over –55°C to 85°C), and typically have little voltage
coefficient. Capacitors with Y5V and/or Z5U temperature characteristic are generally not recommended. These
types of capacitors typically have wide capacitance tolerance ( 80%, –20%), vary significantly over temperature
(Y5V: 22%, –82% over –30°C to 85°C range; Z5U: 22%, –56% over 10°C to 85°C range), and have poor voltage
coefficients. Under some conditions, a nominal 1-µF Y5V or Z5U capacitor could have a capacitance of only
0.1 µF. Such detrimental deviation is likely to cause these Y5V and Z5U of capacitors to fail to meet the
minimum capacitance requirements of the LM2750.
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Table 1 lists some leading ceramic capacitor manufacturers.
Table 1. Suggested Capacitors
MANUFACTURER
CONTACT INFORMATION
TDK
www.component.tdk.com
AVX
www.avx.com
Murata
www.murata.com
Taiyo-Yuden
www.t-yuden.com
Vishay-Vitramon
www.vishay.com
8.2.1.2.2 Input Capacitor
The input capacitor (CIN) is used as a reservoir of charge, helping to quickly transfer charge to the flying
capacitor during the charge phase (φ1) 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 first connected to the input, and helps to
filter noise on the input pin that could adversely affect sensitive internal analog circuitry biased off the input line.
As mentioned above, an X7R/X5R ceramic capacitor is recommended for use. For applications where the
maximum load current required is between 60 mA and 120 mA, a minimum input capacitance of 2 µF is required.
For applications where the maximum load current is 60 mA or less, 1 µF of input capacitance is sufficient. Failure
to provide enough capacitance on the LM2750 input can result in poor part performance, often consisting of
output voltage droop, excessive output voltage ripple and/or excessive input voltage ripple.
A minimum voltage rating of 10 V is recommended for the input capacitor. This is to account for DC bias
properties of ceramic capacitors. Capacitance of ceramic capacitors reduces with increased DC bias. This
degradation can be quite significant (> 50%) when the DC bias approaches the voltage rating of the capacitor.
8.2.1.2.3 Flying Capacitor
The flying capacitor (CFLY) transfers charge from the input to the output, providing the voltage boost of the
doubler. A polarized capacitor (tantalum, aluminum electrolytic, etc.) must not be used here, as the capacitor is
reverse-biased upon start-up of the LM2750. The size of the flying capacitor and its ESR affect output current
capability when the input voltage of the LM2750 is low, most notable for input voltages below 3 V. These issues
were discussed previously in Output Current Capability. For most applications, a 1-µF X7R/X5R ceramic
capacitor is recommended for the flying capacitor.
8.2.1.2.4 Output Capacitor
The output capacitor of the LM2750 plays an important part in determining the characteristics of the output signal
of the LM2750, many of which have already been discussed. The ESR of the output capacitor affects charge
pump output resistance, which plays a role in determining output current capability. Both output capacitance and
ESR affect output voltage ripple. For these reasons, a low-ESR X7R/X5R ceramic capacitor is the capacitor of
choice for the LM2750 output.
In addition to these issues previously discussed, the output capacitor of the LM2750 also affects control-loop
stability of the part. Instability typically results in the switching frequency effectively reducing by a factor of two,
giving excessive output voltage droop and/or increased voltage ripple on the output and the input. With output
currents of 60 mA or less, a minimum capacitance of 1 µF is required at the output to ensure stability. For output
currents between 60 mA and 120 mA, a minimum output capacitance of 2 µF is required.
A minimum voltage rating of 10 V is recommended for the output capacitor. This is to account for DC bias
properties of ceramic capacitors. Capacitance of ceramic capacitors reduces with increased DC bias. This
degradation can be quite significant (> 50%) when the DC bias approaches the voltage rating of the capacitor.
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8.2.1.2.5 Power Efficiency And Power Dissipation
Efficiency of the LM2750 mirrors that of an unregulated switched capacitor converter followed by a linear
regulator. The simplified power model of the LM2750, in Figure 13, is used to discuss power efficiency and
power dissipation. In calculating power efficiency, output power (POUT) is easily determined as the product of the
output current and the 5-V output voltage. Like output current, input voltage is an application-dependent variable.
The input current can be calculated using the principles of linear regulation and switched capacitor conversion. In
an ideal linear regulator, the current into the circuit is equal to the current out of the circuit. The principles of
power conservation mandate the ideal input current of a voltage doubler must be twice the output current. Adding
a correction factor for operating quiescent current (IQ, 5-mA typical) gives an approximation for total input current
which, when combined with the other input and output parameter(s), yields Equation 5 for efficiency:
'=
2176
8176 × +176
×
2+0
8+0 × (2 × +176 + +3 )
(5)
Comparisons of LM2750 efficiency measurements to calculations using Equation 5 have shown a quite accurate
approximation of actual efficiency. Because efficiency is inversely proportional to input voltage, it is highest when
the input voltage is low. In fact, for an input voltage of 2.9 V, efficiency of the LM2750 is greater than 80%
(IOUT ≥ 40 mA) and peak efficiency is 85% (IOUT = 120 mA). The average efficiency for an input voltage range
spanning the Li-Ion range (2.9 V to 4.2 V) is 70% (IOUT = 120 mA). At higher input voltages, efficiency drops
dramatically. In Li-Ion-powered applications, this is typically not a major concern, as the circuit is powered off by
a charger in these circumstances. Low efficiency equates to high power dissipation, however, which could
become an issue worthy of attention.
The LM2750 power dissipation (PD) is calculated simply by subtracting output power from input power:
2& = 2+0 F 2176 = [8+0 × (2 × +176 + +3)] F [8176 × +176 ]
(6)
Power dissipation increases with increased input voltage and output current, up to 772 mW at the ends of the
operating ratings (VIN = 5.6 V, IOUT = 120 mA). Internal power dissipation self-heats the device. Dissipating this
amount power/heat so the LM2750 does not overheat is a demanding thermal requirement for a small surfacemount package. When soldered to a PCB with layout conducive to power dissipation, the excellent thermal
properties of the WSON package enable this power to be dissipated from the LM2750 with little or no derating,
even when the circuit is placed in elevated ambient temperatures.
VIN
IIN = (2 × IOUT) + IQ
SwitchedCapacitor
Doubler
V ' # 2 × VIN
I ' = IOUT
Ideal Linear
Regulator
VOUT = 5 V
(IQ = 0)
IOUT
IQ
Figure 13. LM2750 Model for Power Efficiency and Power Dissipation Calculations
8.2.1.3 Application Curve
Figure 14. Power Efficiency
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8.2.2 LM2750 LED Drive Applications
VIN
2.7 V to 5.6 V
VOUT = 5 V ± 4%
8, 9
VOUT
VIN
CIN
2.2 PF
1, 2
CAP+
SD
...
LED6
R1
...
R6
10
CFLY
1 PF
CAP7
GND
Capacitors:
1 PF - TDK C1608X5R1A105K
2.2PF - TDK C2012X7R1A225K
LED1
COUT
2.2 PF
LM2750-5.0
4
IOUT up to 120 mA, (VIN t 2.9 V)
IOUT up to 40 mA, (VIN t 2.7 V)
ILEDx = (5 V - VLEDx) ÷ Rx
3, 5, 6, DAP
Figure 15. LM2750-5.0 LED Drive Application Circuit
VIN
2.7 V to 5.6 V
VOUT = 1.23 V + VLED1
VOUT Range: 3.8 V to 5.2 V
8, 9
VOUT
VIN
CIN
2.2 PF
For VOUT < 4.9 V:
max VIN= VOUT + 0.7 V
1, 2
LED6
...
R6
3
CAP+
CFLY
1 PF
...
COUT
2.2 PF
LM2750-ADJ
10
LED1
IOUT up to 120 mA
FB
4
SD
CAP7
GND
5, 6, DAP
Capacitors: 1 PF - TDK C1608X5R1A105K
2.2PF - TDK C2012X7R1A225K
R1
ILED1 = 1.23 V ÷ R1
ILEDx = (1.23 V + VLED1 - VLEDx) ÷ Rx
Figure 16. LM2750-ADJ LED Drive Application Circuit
8.2.2.1 Design Requirements
See Design Requirements.
8.2.2.2 Detailed Design Requirements
The LM2750 is an excellent part for driving white and blue LEDs for display backlighting and other generalpurpose lighting functions. The circuits of Figure 15 and Figure 16 show LED driver circuits for the LM2750-5.0
and the LM2750-ADJ, respectively. Simply placing a resistor (R) in series with each LED sets the current through
the LEDs:
+.'& = (8176 F 8.'& ) ÷ 4
(7)
In Equation 7, ILED is the current that flows through a particular LED, and VLED is the forward voltage of the LED
at the given current. As can be seen in the equation above, LED current varies with changes in LED forward
voltage (VLED). Mismatch of LED currents results in brightness mismatch from one LED to the next.
The feedback pin of the LM2750-ADJ can be utilized to help better control brightness levels and negate the
effects of LED forward voltage variation. As shown in Figure 16, connecting the feedback pin to the primary LEDresistor junction (LED1-R1) regulates the current through that LED. The voltage across the primary resistor (R1)
is the feedback pin voltage (1.23 V typical), and the current through the LED is the current through that resistor.
Current through all other LEDs (LEDx) is not regulated, however, and varies with LED forward voltage variations.
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When using the LM2750-ADJ in current-mode, LED currents can be calculated with Equation 8 and Equation 9:
+.'&1 = 1.23 8 ÷ 41
(8)
+.'&T = (1.23 8 +8.'&1 F8.'&T ) ÷4T
(9)
The current-mode configuration does not improve brightness matching from one LED to another in a single
circuit, but keeps currents similar from one circuit to the next. For example: if there is forward voltage mismatch
from LED1 to LED2 on a single board, the current-mode LM2750-ADJ solution provides no benefit. But if the
forward voltage of LED1 on one board is different than the forward voltage of LED1 on another board, the
currents through LED1 in both phones will match. This helps keep LED currents fairly consistent from one
product to the next, and helps to offset lot-to-lot variation of LED forward voltage characteristics.
8.2.2.2.1 LED Driver Power Efficiency
Efficiency of an LED driver (ELED) is typically defined as the power consumed by the LEDs (PLED) divided by the
power consumed at the input of the circuit. Input power consumption of the LM2750 was explained and defined
in the previous section titled: . Assuming LED forward voltages and currents match reasonably well, LED power
consumption is the product of the number of LEDs in the circuit (N), the LED forward voltage (VLED), and the LED
forward current (ILED):
2.'& = 0 ×8.'& ×+.'&
(10)
'.'& = 2.'& ÷ 2+0 = :0 × 8.'& × +.'& ; ÷ {8+0 × >(2 × +176 ; + 5 I#]}
(11)
8.2.2.3 Application Curve
Figure 17 is an efficiency curve for a typical LM2750 LED-drive application.
Figure 17. LM2750 LED Drive Efficiency, 6 LEDs
ILED = 20 mA each, VLED = 4 V
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9 Power Supply Recommendations
The LM2750 is designed to operate from an input voltage supply range between 2.7 V and 5.6 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 device, additional bulk capacitance may be required in addition to the ceramic bypass capacitors.
9.1 LED Driver Power Consumption
For battery-powered LED-drive applications, it is strongly recommended that power consumption, rather than
power efficiency, be used as the metric of choice when evaluating power conversion performance. Power
consumed (PIN) is simply the product of input voltage (VIN) and input current (IIN): PIN = VIN × IIN.
The LM2750 input current is equal to twice the output current (IOUT), plus the supply current of the part (nominally
5 mA): IIN = (2 × IOUT) + 5 mA.
Output voltage and LED voltage do not impact the amount of current consumed by the LM2750 circuit. Thus,
neither factor affects the current draw on a battery. Because output voltage does not impact input current, there
is no power savings with either the LM2750-5.0 or the LM2750-ADJ; both options consume the same amount of
power.
In LED Driver Power Efficiency, LED Driver Efficiency was defined in Equation 11.
Equation 11 can be simplified by recognizing
• 2 × IOUT > 5 mA (high output-current applications);
• N × ILED = IOUT
Thus, simplification yields: ELED = VLED / VIN.
This is in direct contrast to the previous assertion that showed that power consumption was completely
independent of LED voltage. As is the case here with the LM2750, efficiency is often not a good measure of
power conversion effectiveness of LED driver topologies. This is why it is strongly recommended that power
consumption be studied or measured when comparing the power conversion effectiveness of LED drivers.
Additionally, efficiency of an LED drive solution must not be confused with an efficiency calculation for a standard
power converter (EP).
'2 = 2176 ÷ 2+0 = :8176 × +176 ; ÷ (8+0 × ++0 )
(12)
Equation 12 neglects power losses in the external resistors that set LED currents and is a very poor metric of
LED-drive power conversion performance.
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10 Layout
10.1 Layout Recommendations
A good board layout of the LM2750 circuit is required to achieve optimal assembly, electrical, and thermal
dissipation performance. Figure 18 is an example of a board layout implementing recommended techniques. For
more information related to layout for the WSON/SON package, see Texas Instruments AN-1187 Leadless
Leadframe Package (LLP) (SNOA401).
General guidelines for board layout are:
• Place capacitors as close to the as possible to the LM2750, and on the same side of the board. VIN and VOUT
connections are most critical: run short traces from the LM2750 pads directly to these capacitor pads.
• Connect the ground pins of the LM2750 and the capacitors to a good ground plane. The ground plane is
essential for both electrical and thermal disspation performance.
• For optimal thermal performance, make the ground plane(s) as large as possible. Connect the die-attach pad
(DAP) of the LM2750 to the ground plane(s) with wide traces and/or multiple vias. Top-layer ground planes
are most effective in increasing the thermal dissipation capability of the WSON package. Large internal
ground planes are also very effective in keeping the die temperature of the LM2750 within operating ratings.
10.2 Layout Example
Figure 18. LM2750-5.0 Recommended Layout
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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 Documentation Support
11.2.1 Related Documentation
For related documentation see the following:
Texas Instruments AN-1187 Leadless Leadframe Package (LLP) (SNOA401).
11.2.2 Related Links
Table 2 lists quick access links. Categories include technical documents, support and community resources,
tools and software, and quick access to sample or buy.
Table 2. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
LM2750
Click here
Click here
Click here
Click here
Click here
LM2750-ADJ
Click here
Click here
Click here
Click here
Click here
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.
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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.
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PACKAGE OPTION ADDENDUM
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8-Oct-2015
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
LM2750LD-5.0/NOPB
ACTIVE
WSON
NGY
10
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
-40 to 85
S002B
LM2750LD-ADJ/NOPB
ACTIVE
WSON
NGY
10
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
-40 to 85
S003B
LM2750LDX-5.0/NOPB
ACTIVE
WSON
NGY
10
4500
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
-40 to 85
S002B
LM2750SD-5.0/NOPB
ACTIVE
WSON
DSC
10
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
S005B
LM2750SD-ADJ/NOPB
ACTIVE
WSON
DSC
10
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 85
S004B
LM2750SDX-5.0/NOPB
ACTIVE
WSON
DSC
10
4500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
LM2750SDX-ADJ/NOPB
ACTIVE
WSON
DSC
10
4500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
S005B
-40 to 85
S004B
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
8-Oct-2015
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
2-Sep-2015
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM2750LD-5.0/NOPB
WSON
NGY
10
1000
178.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
LM2750LD-ADJ/NOPB
WSON
NGY
10
1000
178.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
LM2750LDX-5.0/NOPB
WSON
NGY
10
4500
330.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
LM2750SD-5.0/NOPB
WSON
DSC
10
1000
178.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
LM2750SD-ADJ/NOPB
WSON
DSC
10
1000
178.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
LM2750SDX-5.0/NOPB
WSON
DSC
10
4500
330.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
LM2750SDX-ADJ/NOPB
WSON
DSC
10
4500
330.0
12.4
3.3
3.3
1.0
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
2-Sep-2015
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM2750LD-5.0/NOPB
WSON
NGY
10
1000
213.0
191.0
55.0
LM2750LD-ADJ/NOPB
WSON
NGY
10
1000
213.0
191.0
55.0
LM2750LDX-5.0/NOPB
WSON
NGY
10
4500
367.0
367.0
35.0
LM2750SD-5.0/NOPB
WSON
DSC
10
1000
210.0
185.0
35.0
LM2750SD-ADJ/NOPB
WSON
DSC
10
1000
210.0
185.0
35.0
LM2750SDX-5.0/NOPB
WSON
DSC
10
4500
367.0
367.0
35.0
LM2750SDX-ADJ/NOPB
WSON
DSC
10
4500
367.0
367.0
35.0
Pack Materials-Page 2
MECHANICAL DATA
DSC0010A
SDA10A (Rev A)
www.ti.com
MECHANICAL DATA
NGY0010A
LDA10A (Rev B)
www.ti.com
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