NSC LM2750-5.0MDC, LM2750-5.0EV, LM2750LDX-5.0, LM2750-5.0MWC Datasheet
LM2750
Low Noise, 5.0V Regulated Switched Capacitor Voltage
Converter
General Description
The LM2750 is a switched-capacitor doubler that produces a
low-noise, well regulated, 5.0V output. It can supply up to
120mA of output current over a 2.9V to 5.6V input range, as
well as up to 40mA of output current when the input voltage
is as low as 2.7V. The LM2750 has been placed in National’s
10-pin LLP, a package with excellent thermal properties that
keeps the part from overheating under almost all rated operating conditions
A perfect fit for space-constrained, battery-powered applications, the LM2750 requires only 3 external components: one
input capacitor, one output capacitor, and one flying capacitor. Small, inexpensive ceramic capacitors are recommended for use. These capacitors, in conjunction with the
1.7MHz fixed switching frequency of the LM2750, yield low
output voltage ripple, beneficial for systems requiring a lownoise 5V supply. Pre-regulation minimizes input current
ripple, 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 connected
devices in the event of output shorts or excessive current
loads.
Features
n Inductorless solution: Application requires only 3 small
ceramic capacitors
n Low Noise, 5.0V
±
4% Regulated Output
n 85% Peak Efficiency
70% Average Efficiency over Li-Ion Input Range
(2.9V-to-4.2V)
n Output Current up to 120mA with 2.9V ≤ V
IN
≤ 5.6V
Output Current up to 40mA with 2.7V ≤ V
IN
≤ 2.9V
n Wide Input Voltage Range: 2.7V to 5.6V
n Fixed 1.7MHz switching frequency for a low-noise,
low-ripple output signal
n Pre-regulation minimizes input current ripple, keeping
the battery line (V
IN
) virtually noise-free
n Tiny LLP package with outstanding power dissipation:
Usually no derating required.
n Shutdown Supply Current less than 2µA
Applications
n White and Colored LED-based Display Lighting
n Cellular Phone SIM cards
n Audio Amplifier Power Supplies
n General Purpose Li-Ion-to-5V Conversion
Typical Application Circuit
20035101
February 2003
LM2750 Low Noise, 5.0V Regulated Switched Capacitor Voltage Converter
© 2003 National Semiconductor Corporation DS200351 www.national.com
Connection Diagram
LM2750
10-Pin Leadless Leadframe Package (LLP) - 3mm X 3mm
NS Package Number LDA10A
20035102
Top View
Pin Description
Pin #(s) Pin Name Description
8, 9 V
IN
Input Voltage - The pins must be connected externally.
1, 2 V
OUT
Output Voltage - These pins must be connected externally.
10 CAP+ Flying Capacitor Positive Terminal
7 CAP- Flying Capacitor Negative Terminal
4SD
Active-Low Shutdown Input. A 200kΩ resistor is connected internally between
this pin and GND to pull the voltage on this pin to 0V, and shut down the part,
when the pin is left floating.
3, 5, 6, DAP GND Ground - These pins must be connected externally.
Ordering Information
Output Voltage
Option
Ordering
Information
Package Marking Supplied as
5.0 LM2750LD-5.0 S002B 1000 Units, Tape and Reel
5.0 LM2750LDX-5.0 S002B 4500 Units, Tape and Reel
LM2750
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Absolute Maximum Ratings (Notes 1,
2)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
V
IN
Pin: Voltage to Ground −0.3V to 6V
SD Pin: Voltage to GND
−0.3V to
(V
IN
+0.3V)
Junction Temperature (T
J-MAX-ABS
) 150˚C
Continuous Power Dissipation Internally Limited
(Note 3)
Storage Temperature Range −65˚C to 150˚C
Maximum Lead Temperature 260˚C
(Soldering, 5 sec.)
ESD Rating (Note 4)
Human-body model:
Machine model
2kV
100V
Operating Ratings (Notes 1, 2)
Input Voltage Range 2.7V to 5.6V
Recommended Output Current
2.9V ≤ V
IN
≤ 5.6V 0 to 120mA
2.7V ≤ V
IN
≤ 2.9V 0 to 40mA
Junction Temperature (T
J
) Range -40˚C to 125˚C
Ambient Temperature (T
A
) Range -40˚C to 85˚C
(Note 5)
Thermal Information
Junction-to-Ambient Thermal
Resistance, LLP-10 55˚C/W
Package (θ
JA
) (Note 6)
Electrical Characteristics (Notes 2, 7)
Typical values and limits in standard typeface apply for TJ=25oC. Limits in boldface type apply over the operating junction
temperature range. Unless otherwise specified: 2.9V ≤ V
IN
≤ 5.6V, V(SD) = VIN,C
FLY
= 1µF, CIN= 2 x 1µF, C
OUT
=2x1µF
(Note 8).
Symbol Parameter Conditions Min Typ Max Units
V
OUT
Output Voltage
2.9V ≤ V
IN
≤ 5.6V,
I
OUT
≤ 120mA
4.80
(-4%)
5.0 5.20
(+4%)
V
(%)
2.7V ≤ V
IN
≤ 2.9V,
I
OUT
≤ 40mA
4.80
(-4%)
5.0 5.20
(+4%)
I
Q
Operating Supply Current I
OUT
= 0mA,
V
IH(MIN)
≤ V(SD) ≤V
IN
51012mA
I
SD
Shutdown Supply Current V(SD) = 0V 2 µA
V
R
Output Ripple C
OUT
= 10µF, I
OUT
= 100mA 4
mVp-p
C
OUT
=2.2µF, I
OUT
= 100mA 15
E
PEAK
Peak Efficiency VIN= 2.7V, I
OUT
= 40mA 87 %
V
IN
= 2.9V, I
OUT
= 120mA 85
E
AVG
Average Efficiency over Li-Ion
Input Range (Note 10)
VINRange: 2.9V - 4.2V,
I
OUT
= 120mA
70 %
V
IN
Range: 2.9V - 4.2V,
I
OUT
= 40mA
67
f
SW
Switching Frequency 1.0 1.7 MHz
t
ON
V
OUT
Turn-On Time VIN= 3.0V, I
OUT
= 100mA,
(Note 9)
0.5 ms
I
LIM
Current Limit V
OUT
shorted to GND 300 mA
Shutdown Pin (SD) Characteristics
V
IH
Logic-High SD Input 1.3 V
IN
V
V
IL
Logic-Low SD Input 0 0.4 V
I
IH
SD Input Current (Note 11) 1.3V ≤ V(SD) ≤ V
IN
15 50 µA
I
IL
SD Input Current V(SD) = 0V −1 1 µA
Capacitor Requirements
C
IN
Required Input
Capacitance(Note 12)
I
OUT
≤ 60mA 1.0 µF
60mA ≤ I
OUT
≤ 120mA 2.0
C
OUT
Required Output
Capacitance(Note 12)
I
OUT
≤ 60mA 1.0 µF
60mA ≤ I
OUT
≤ 120mA 2.0
LM2750
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Electrical Characteristics (Notes 2, 7) (Continued)
Note 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 guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the
Electrical Characteristics tables.
Note 2: All voltages are with respect to the potential at the GND pin.
Note 3: Thermal shutdown circuitry protects the device from permanent damage.
Note 4: The Human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200pF capacitor discharged
directly into each pin.
Note 5: Maximum ambient temperature (T
A-MAX
) is dependent on the maximum operating junction temperature (T
J-MAX-OP
= 125oC), the maximum power
dissipation of the device in the application (P
D-MAX
), and the junction-to ambient thermal resistance of the part/package in the application (θJA), as given by the
following equation: T
A-MAX=TJ-MAX-OP
-(θJAxP
D-MAX
). Maximum power dissipation of the LM2750 in a given application can be approximated using the following
equation: P
D-MAX
=(V
IN-MAXxIIN-MAX
)-(V
OUTxIOUT-MAX
)=[V
IN-MAX
x((2xI
OUT-MAX
) + 5mA)] - (V
OUTxIOUT-MAX
). In this equation, V
IN-MAX,IIN-MAX
, and
I
OUT-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 85
o
C is determined under the following application conditions: θJA=55oC/W, P
D-MAX
= 727mW (achieved when
V
IN-MAX
= 5.5V and I
OUT-MAX
= 115mA, for example). Maximum ambient temperature must be derated by 1.1oC for every increase in internal power dissipation of
20mW above 727mW (again assuming that θ
JA
=55oC/W in the application). For more information on these topics, please refer to Application Note 1187: Leadless
Leadframe Package (LLP) and the Power Efficiency and Power Dissipation section of this datasheet.
Note 6: Junction-to-ambient thermal resistance (θ
JA
) is taken from a thermal modeling result, performed under the conditions and guidelines set forth in the JEDEC
standard JESD51-7. The test board is a 4 layer FR-4 board measuring 102mm x 76mm x 1.6mm witha2x1array of thermal vias. The ground plane on the board
is 50mm x 50mm. Thickness of copper layers are 36mm/18 mm /18 mm /36 mm (1.5oz/1oz/1oz/1.5oz). Ambient temperature in simulation is 22˚C, still air. Power
dissipation is 1W.
The value of θ
JA
of the LM2750 in LLP-10 could fall in a range as wide as 50oC/W to 150oC/W (if not wider), depending on PCB material, layout, and environmental
conditions. In applications where high maximum power dissipation exists (high V
IN
, high I
OUT
), special care must be paid to thermal dissipation issues. For more
information on these topics, please refer to Application Note 1187: Leadless Leadframe Package (LLP) and the Power Efficiency and Power Dissipation
section of this datasheet. and the following sections of this datasheet:
Note 7: All room temperature limits are 100% tested or guaranteed through statistical analysis. All limits at temperature extremes are guaranteed by correlation
using standard Statistical Quality Control methods (SQC). All limits are used to calculate Average Outgoing Quality Level (AOQL). Typical numbers are not
guaranteed, but do represent the most likely norm.
Note 8: C
FLY,CIN
, and C
OUT
: Low-ESR Surface-Mount Ceramic Capacitors (MLCCs) used in setting electrical characteristics
Note 9: Turn-on time is measured from when SD signal is pulled high until the output voltage crosses 90% of its final value.
Note 10: Efficiency is measured versus VIN, with VINbeing swept in small increments from 3.0V to 4.2V. The average is calculated from these measurements
results. Weighting to account for battery voltage discharge characteristics (V
BAT
vs. Time) is not done in computing the average.
Note 11: SD Input Current (I
IH
) is due to a 200kΩ (typ.) pull-down resistor connected internally between the SD pin and GND.
Note 12: Limit is the minimum required output capacitance to ensure proper operation. This electrical specification is guaranteed by design.
Block Diagram
20035103
LM2750
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