LM3262_15 Datasheet, PDF (1/27 Pages) Texas Instruments – LM3262 6MHz, 800 mA Miniature, Adjustable, Step-Down DC-DC Converter with Auto Bypass for RF Power Amplifiers

LM3262
www.ti.com
SNVS875N – AUGUST 2012 – REVISED MARCH 2013
LM3262 6MHz, 800 mA Miniature, Adjustable, Step-Down DC-DC
Converter with Auto Bypass for RF Power Amplifiers
Check for Samples: LM3262
FEATURES
1
•2 6MHz (typ.) PWM Switching Frequency
• Operates from a Single Li-Ion Cell (2.5V to
5.5V)
• Adjustable Output Voltage (0.4V to 3.6V)
• 800 mA Maximum Load Capability (up to 1A in
Bypass)
• High Efficiency (93% typ. at 3.8V_IN, 3.4V_OUT at
500 mA)
• Automatic ECO/PWM/BP Mode Change
• 9-bump DSBGA Package
• Current and Thermal Overload Protection
• Multi-function VCON Pin (eliminates need for
separate BPEN control)
• Soft-Start Function
• Small Chip Inductor in 0805 (2012) case size
• 25 µA typical I_q in Sleep Mode
• 5 µs typical rise/fall time for 2V step
APPLICATIONS
• HSUPA, LTE Cellular Phones
• TD-SCDMA and TD-LTE
• Hand-Held Radios
• RF PC Cards
• Battery-Powered RF Devices
• USB-Powered Portable Applications
DESCRIPTION
The LM3262 is a DC-DC converter optimized for
powering RF power amplifiers (PAs) from a single
Lithium-Ion cell; however, it may be used in many
other applications such as USB-powered portable
applications. The device's 2.5V to 5.5V input voltage
can be stepped down to an adjustable output voltage
range from 0.4V to 3.6V. Output voltage is set using
a VCON analog input which enables improved RF
stage PA efficiencies.
The LM3262 offers five modes of operation. In Pulse
Width Modulation (PWM) mode the device operates
at a fixed frequency of 6 MHz (typ.) which minimizes
RF interference at medium-to-low loads. 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 battery life. Shutdown mode turns the device off
and reduces battery consumption to 0.1 µA (typ.). At
low-battery condition Bypass mode reduces the
voltage dropout to less than 50 mV (typ.). The part
also features a Sleep mode.
The LM3262 is available in a 9-bump lead-free
DSBGA package. A high switching frequency (6 MHz)
allows use of only three tiny surface-mount
components: one inductor and two ceramic
capacitors.
TYPICAL APPLICATION CIRCUIT
V_IN
2.5V to 5.5V
10 PF
GPO1
DAC
VIN
BPEN
SW
EN
LM3262
FB
VCON
SGND PGND
0.5 PH
V_OUT = 2.5 x VCON
0.4V to 3.6V
4.7 PF
1
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2
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 © 2012–2013, Texas Instruments Incorporated