LM2757 Datasheet, PDF (1/27 Pages) National Semiconductor (TI) – Switched Capacitor Boost Regulator with High Impedance Output in Shutdown

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LM2757
SNVS536F – OCTOBER 2007 – REVISED JULY 2015
LM2757 Switched-Capacitor Boost Regulator With High Impedance Output in Shutdown
1 Features
•1 Dual Gain Converter (2×, 3/2×) With up to 93%
Efficiency
• Inductorless Solution Uses Only 4 Small Ceramic
Capacitors
• Total Solution Area < 12 mm²
• True Input-Output and Output-Input Disconnect
• Up to 180-mA Output Current Capability (5 V)
• Selectable 4.1-V, 4.5-V or 5-V Output
• Pre-Regulation Minimizes Input Current Ripple
• 1.24-MHz Switching Frequency for Low-Noise,
Low-Ripple Output Voltage
• Integrated Overcurrent and Thermal Shutdown
Protection
2 Applications
• USB/USB-OTG/HDMI Power
• Supercapacitor Charger
• Keypad LED Drive
• Audio Amplifier Power Supply
• Low-Current Camera Flash
• General Purpose Li-Ion-to-5-V Conversion
• Cellular Phone SIM Cards
3 Description
The LM2757 is a constant-frequency pre-regulated
switched-capacitor charge pump that operates at
1.25 MHz to produce a low-noise regulated output
voltage. The device can be configured to provide up
to 100 mA at 4.1 V, 110 mA at 4.5 V, or 180 mA at 5
V. Excellent efficiency is achieved without the use of
an inductor by operating the charge pump in a gain of
either 3/2 or 2 according to the input voltage and
output voltage option selection.
The LM2757 presents a high impedance at the V_OUT
pin when shut down. This allows for use in
applications that require the regulated output bus to
be driven by another supply while the LM2757 is shut
down.
The LM2757 device comes in a tiny 12-pin 0.4-mm
pitch DSBGA package. A perfect fit for space-
constrained, battery-operated applications, the device
requires only 4 small, inexpensive ceramic
capacitors. Built-in soft-start, overcurrent protection,
and thermal shutdown features are also included in
this device.
Device Information⁽¹⁾
PART NUMBER
PACKAGE
BODY SIZE (MAX)
LM2757
DSBGA (12)
1.641 mm × 1.581 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application
V_IN = 3 V - 5.5 V
C_IN
1 µF
C₁
0.47 µF
C₂
0.47 µF
VIN
B2,B3
C1+
A3
B1 _C1-
A1 ^C2+
C3
C2-
VOUT
V_OUT = 4.1 V (100 mA), 4.5 V (110 mA)
5 V (180 mA)
A2
1 µF
C_OUT
LM2757
M0
D3
M1
D2
GND
C1,C2
*Bump D1 is No Connect (NC)
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.