LM3242 PRODUCT BRIEF
October 17, 2011
General Description
The LM3242 is a DC-DC converter optimized for powering RF
power amplifiers (PAs) from a single Lithium-Ion cell; howev-
er, it may be used in many other applications. It steps down
an input voltage from 2.7V to 5.5V to an adjustable output
voltage from 0.4V to 3.6V. Output voltage is set using a VCON
analog input for controlling power levels and efficiency of the
RF PA.
The LM3242 offers five modes of operation. In PWM mode
the device operates at a fixed frequency of 6MHz (typ.) at
medium-to-heavy load range and minimizes RF interference.
At light load, the device enters into ECO mode automatically
and operates with reduced switching frequency. In ECO
mode, the quiescent current is reduced and extends the bat-
tery life. Shutdown mode turns the device off and reduces
battery consumption to 0.1 µA (typ.). In low-battery condition,
Bypass mode reduces the voltage dropout to less than 50 mV
(typ.). The part also features a Sleep mode.
The LM3242 is available in a 9-bump lead-free micro SMD
package. A high switching frequency (6MHz) allows use of
only three tiny surface-mount components: one inductor and
two ceramic capacitors.
Notice: This document is not a datasheet. For more in-
formation regarding this product or to order samples
please contact your local National Semiconductor/Texas
Instruments sales office or visit http://focus.ti.com/gen-
eral/docs/dsnsuprt.tsp.
Features
■6MHz (typ.) PWM Switching Frequency
■Operates from a Single Li-Ion Cell (2.7V to 5.5V)
■Adjustable Output Voltage (0.4V to 3.6V)
■750 mA Maximum Load Capability (up to 1A in Bypass)
■High Efficiency (95% typ. at 3.9VIN, 3.3VOUT at 500 mA)
■Automatic ECO/PWM/BP mode change
■9-bump micro SMD Package
■Current Overload Protection
■Thermal Overload Protection
■Soft-Start Function
■Small Chip Inductor in 0805 (2012) case size
Applications
■Battery-Powered 3G/4G RF Power Amplifiers
■Hand-Held Radios
■RF PC Cards
■Battery-Powered RF Devices
Typical Application
30122201
© 2011 National Semiconductor Corporation 301222 www.national.com
LM3242 PRODUCT BRIEF
Physical Dimensions inches (millimeters) unless otherwise noted
9-Bump Thin Micro SMD, Large Bump (0.4 mm pitch)
NS Package Number TMD09
X1 = 1.35 mm ±0.030 mm
X2 = 1.488 mm ±0.030 mm
X3 = 0.6 mm ±0.075 mm
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Notes
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LM3242 PRODUCT BRIEF
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