LM3200 Miniature, Adjustable, Step-Down DC-DC Converter with Bypass Mode for RF Power Amplifiers
November 2004
LM3200 ...
LM3200 Miniature, Adjustable, Step-Down DC-DC Converter with Bypass Mode for RF Power
Amplifiers
November 2004
LM3200 Miniature, Adjustable, Step-Down DC-DC Converter with Bypass Mode for RF Power
Amplifiers
General Description
The LM3200 is a DC-DC converter optimized for powering RF power
amplifiers (PAs) from a single Lithium-Ion cell. It steps down an input
voltage of 2.7V to 5.5V to a variable output
voltage of 0.8V to 3.6V. The output
voltage is set using an analog input ( VCON) for optimizing efficiency of the RF PA at various power levels. The LM3200 offers superior features and performance for mobile phones and similar RF PA applications. Fixedfrequency PWM mode minimizes RF interference. Bypass mode turns on an internal bypass switch to power the PA directly from the battery. LM3200 has both forced and automatic bypass modes. Shutdown mode turns the device off and reduces battery consumption to 0.1 µA (typ.). The LM3200 is available in a 10-pin lead free micro SMD package. A high switching frequency (2 MHz) allows use of tiny surface-mount components. Only three small external surface-mount components, an inductor and two ceramic
capacitors are required.
Features
2 MHz (typ.) PWM Switching Frequency Operates from a single Li-Ion cell (2.7V to 5.5V) Variable Output
Voltage (0.8V to 3.6V) 300 mA Maximum load capability (PWM mode) 500 mA Maximum load capability (Bypass mode) PWM, Forced and Automatic Bypass Mode High Efficiency (96% Typ at 3.6VIN, 3.2VOUT at 120 mA)...