A Product Line of Diodes Incorporated PAM2321 3MHz, FAST TRANSIENT 2A STEP-DOWN CONVERTER Description Pin Assignments The PAM2321 is a 2A step-down converter with a typical input voltage of 3.3V and a fixed output voltage of 1.2V or an adjustable output. The 3MHz switching frequency enables the use of small external components. The ultra-small 3mmx3mm footprint and high efficiency make the PAM2321 an ideal choice for portable applications. The PAM2321 delivers 2A maximum output current while consuming only 55A no-load quiescent current. Low R integrated DS(ON) MOSFETs and 100% duty cycle operation make the PAM2321 the ideal choice for high output voltage, high current applications which require a low dropout threshold. The PAM2321 provides excellent transient response and output accuracy across the operating range. The PAM2321 maintains high efficiency throughout the load range. The PAM2321 automatically optimizes efficiency during light load mode (PSM) and maintains constant frequency and low output ripple during PWM mode. Applications Over-temperature and short circuit protection safeguard the PAM2321 and system components from damage. Cellular Phone Digital Cameras The PAM2321 are available in Pb-free, ultrasmall, low profile, Hard Disk Drives TDFN3X3-10 package. The product is rated over a temperature range MP3 Players of -40C to +85C. PDAs and Handheld Computers Portable Media Players USB Devices Features Wireless Network Cards 2A Maximum Output Current Tiny 0.47H Chip Inductor Excellent Transient Response Input Voltage: 2.7V to 5.5V Fixed or Adjustable Output Voltage Options: Fixed Output Voltage: 1.2V Adjustable Output Voltage: 1.0V to V IN High Efficiency with 3MHz Switching Frequency 55A No Load Quiescent Current 100% Duty Cycle Low-Dropout Operation Internal Soft-Start Over-Temperature and Current Limit Protection <1A Shutdown Current -40C to +85C Temperature Range Pb-Free/Halogen Free Package RoHS/REACH Compliant 1 of 11 January 2013 PAM2321 Diodes Incorporated www.diodes.com Document number: DSxxxxx Rev. 2 - 1 A Product Line of Diodes Incorporated PAM2321 Typical Applications Circuit = 0.6 * (1 + R1/ R2 ) V OUT Pin Descriptions Pin Function Name PGND Main power ground return pin. Connect to the output and input capacitor return. PVIN Input power supply tied to the source of the high side P-Channel MOSFET. VIN Power supply supplies power for the internal circuitry. Feedback input pin. This pin is connected directly to the converter output for the 1.2V fixed output version, or connected to an FB external resistor divider for the adjustable output version. Analog ground. This pin is internally connected to the analog ground of the control circuitry. AGND Enable pin. A logic low disables the converter and it consumes less than 1 A of current. When connected high, it resumes normal EN operation. Switching node. Connect the inductor to this pin. It is internally connected to the drain of both high and low side MOSFETs. SW Exposed pad of the package provides both electrical contact to the ground and good thermal EP contact to the PCB. This pad must be soldered to the PCB for proper operation. Functional Block Diagram 2 of 11 January 2013 PAM2321 Diodes Incorporated www.diodes.com Document number: DSxxxxx Rev. 2 - 1