GENERAL DESCRIPTION
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 (VOUT) from 0.5 V to the input
voltage (VIN) 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 VIN to low VOUT conversion at
a high frequency.
The EVAL-LTC3313EV-A-Z runs in forced continuous mode with a
2 MHz switching frequency (fSW); 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 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 VIN EMI terminal. The EMI performance of the board-
EVAL-LTC3313EV-A-Z is shown in the EMI Test Results section.
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 this 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.

FEATURES
► 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
EVALUATION KIT CONTENTS
► EVAL-LTC3313EV-A-Z evaluation board
DOCUMENTS NEEDED
► LTC3313 data sheet
► EVAL-LTC3313EV-A-Z user guide
EQUIPMENT NEEDED
► A DC voltage source
► An electronic load
► A multimeter