LM3203_16 Datasheet, PDF (1/22 Pages) Texas Instruments – Step-Down DC-DC Converter

LM3203
www.ti.com
SNVS355D – MAY 2005 – REVISED APRIL 2013
LM3203 Step-Down DC-DC Converter with Bypass Mode for CDMA / WCDMA RF Power
Amplifiers
Check for Samples: LM3203
FEATURES
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•2 2MHz (Typ.) PWM Switching Frequency
• Operates from a Single Li-Ion Cell (2.7V to
5.5V)
• Adjustable Output Voltage (0.8V to 3.6V)
• 500mA Maximum Load Capability (PWM and
Bypass Mode)
• PWM / Forced Bypass Mode
• Low R_DSON Bypass FET: 85mΩ (Typ.)
• High Efficiency (96% typ. at 3.6V_IN, 3.2V_OUT at
150mA)
• Fast Turn-On Time When Enabled (50µs typ.),
3GPP Compliant
• 10-Pin DSBGA Package
• Current Overload Protection
• Thermal Overload Protection
DESCRIPTION
The LM3203 is a DC-DC converter optimized for
powering RF power amplifiers (PAs) from a single
Lithium-Ion cell. However, they may be used in many
other applications. It steps down an input voltage of
2.7V to 5.5V to an adjustable output voltage of 0.8V
to 3.6V. The output voltage is set using a V_CON
analog input and external resistor dividers for
optimizing efficiency of the RF PA at various power
levels.
The LM3203 offers 3 modes for mobile phones and
similar RF PA applications. Fixed-frequency PWM
mode minimizes RF interference. Bypass mode turns
on an internal bypass switch to power the PA directly
from the battery. Shutdown mode turns the device off
and reduces battery consumption to 0.1µA (typ.).
The LM3203 is available in a 10-pin lead free DSBGA
package. A high switching frequency (2MHz) allows
use of tiny surface-mount components.
APPLICATIONS
• Cellular Phones
• Hand-Held Radios
• RF PC Cards
• Battery Powered RF Devices
TYPICAL APPLICATION
V_IN
2.7V to 5.5V
C1
10 PF
C5
0.1 PF
V_CON
0.267V to 1.20V
V_DD PV_IN BYPOUT
SW
LM3203
EN
BYP
FB
V_CON
SGND
PGND
L1
3.3 PH
C3
10 pF
R1
267k
R2
133k
V_OUT
0.8V to 3.6V
C2
4.7 PF
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
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 © 2005–2013, Texas Instruments Incorporated