Analog Devices LTC3119 | Demoboard DC2129A

Description

Demonstration circuit 2129A features the LTC®3119, an18V, 5A synchronous buck/boost DC/DC converter. TheDC2129A has been designed for an input voltage rangeof 2.5V to 18V with an output voltage (VOUT) set to 5V.For VIN > 5V the output current can be as high as 5A. Theunique 4-switch, single inductor architecture provides lownoise and seamless operation from input voltages above,below, or equal to the output voltage.The LTC3119 features selectable PWM or Burst Mode®operation, and an easily synchronizable oscillator. Ajumper JP3, is provided to select the operating mode. Aclock signal can also be applied to JP3 if synchronizationis desired. The demo board is configured for a switchingfrequency of 750kHz. Jumper JP1 is provided to enablethe converter. Resistors R8 and R9 can be used to set anaccurate turn-on voltage of the converter.Typical demo board efficiency is shown in Figure 1 forseveral input voltages as a function of load current. Consultthe data sheet for more information. The transient responseof the converter is shown in Figure 2 and Figure 3. Theconverter is built on a four layer board using 2oz copperon each layer for better thermal performance. The spacingbetween the layers has been reduced so the overallboard thickness is 0.031 inches allowing for better heattransfer between layers and aiding in heat distributionacross the board. The thermal performance of the demoboard is shown in Figure 4. The converter can also operatein a maximum power point control mode by settingthe JP2 jumper to the ON position. The MPPC point canbe adjusted by changing R10 and R11. Consult the datasheet for more information.The LTC3119 data sheet has detailed information about theoperation, specifications, and applications of the device.The data sheet should be read in conjunction with thisquick start guide.

More information

• Datasheet
• IC product information