LTC3313

• EVAL-LTC3313EV-MULTI-AZ evaluation board
• Transient circuit included for load transient evaluation
• RT pin pull-up option for external clock synchronization

The EVAL-LTC3313EV-MULTI-AZ features the LTC3313, a 15 A, low-voltage, synchronous step-down Silent Switcher®, operating as a multiphase 2 MHz, 3.0 V to 5.5 V input, 1.2 V buck regulator. The EVAL-LTC3313EV-MULTI-AZ has three build options to provide 2-phase 30 A, 3-phase 45 A, or 4-phase 60 A output solutions. The LTC3313 supports adjustable output voltages from 0.5 V to input voltage (V_IN) and operating frequencies from 500 kHz up to 5 MHz in multiphase operation.

All phases of EVAL-LTC3313EV-MULTI-AZ operate in forced continuous mode at 2 MHz switching frequency (fSW). The LTC3313 can also synchronize to an external clock using a MODE/SYNC turret when the RT pin of the main phase is pulled up to the V_IN pin.

The EVAL-LTC3313EV-MULTI-AZ also has an electromagnetic interference (EMI) filter to reduce conducted EMI. This EMI filter can be included by applying the input voltage at the V_IN EMI terminal.

Figure 4 shows the efficiency of the circuit with a 3.3 V input for all three build options.

An on-board transient circuit is included to measure fast transient performance.

The LTC3313 data sheet gives a complete description of the part, operation, and application information. The data sheet must be read in conjunction with this user guide. The LTC3313 is assembled in a 3 mm × 3 mm LQFN package with exposed pads for low thermal resistance. The layout recommendations for low EMI operation and maximum thermal performance are available in the LTC3313 data sheet.

• EVAL-LTC3313EV-A-Z evaluation board
• Transient circuit included for load transient evaluation
• EMI filter included to reduce noise in EMI emission tests
• MODE pin pull-up option for pulse-skipping mode evaluation

The EVAL-LTC3313EV-A-Z features the LTC3313, 15 A low voltage synchronous step-down Silent Switcher^® that operates as a 2 MHz, 2.25 V to 5.5 V input, 1.2 V, 15 A output buck regulator. The LTC3313 supports an output voltage (V_OUT) from 0.5 V to the input voltage (V_IN) with operating frequencies from 500 kHz up to 5 MHz. The LTC3313 is a compact, ultralow emission, high-efficiency, and high speed synchronous monolithic step-down switching regulator. The Silent Switcher technology optimizes fast-current loops and makes it easier to minimize electromagnetic interference (EMI) and electromagnetic compatibility (EMC) emissions. The minimum on-time of 35 ns typical enables high V_IN to low V_OUT conversion at a high frequency.

The EVAL-LTC3313EV-A-Z runs in forced continuous mode with a 2 MHz switching frequency (f_SW); however, it can be configured to run at different switching frequencies or in pulse-skipping mode. The LTC3313 oscillator can also synchronize to an external clock using a MODE/SYNC turret, with the EVAL-LTC3313EV-A-Z default setup. Figure 4 in the user guide shows the efficiency and power loss of the EVALLTC3313EV-A-Z with a 3.3 V input in both operation modes.

The EVAL-LTC3313EV-A-Z also has an EMI filter to reduce conducted EMI. This EMI filter can be included by applying the input voltage at the V_IN EMI terminal. The EMI performance of the board-EVAL-LTC3313EV-A-Z is shown in the EMI Test Results section of the user guide. The red lines in the EMI performance graphs illustrate the CISPR25 Class 5 peak limits for the conducted and radiated emission tests. The LTC3313 data sheet gives a complete description of the device and its application information. The data sheet must be read in conjunction with the evaluation board user guide. The LTC3313 is assembled in a 3 mm × 3 mm LQFN package with an exposed pad for low thermal resistance. The layout recommendations for low EMI operation and maximum thermal performance are available in the LTC3313 data sheet.