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Switched Capacitor Voltage Converter

DC1449A: Demo Board for the LT8415 Ultralow Power Boost Converter with Dual Half-Bridge Switches.

DC187A-A: Demo Board for the LT1374 4.5A, 500kHz Step-Down Switching Regulator.

Demonstration circuit DC2247A is a synchronous 2MHz boost LED driver featuring the LT®3922. The LT3922 features a low EMI Silent Switcher architecture and an optional spread spectrum frequency modulation (SSFM) that further reduces EMI. It has a 2A/36V internal power switch, but the demo board has been configured to use a 4V to 28V input and thus has input overvoltage lockout set at 28V. It drives a single string of LEDs at 330mA up to 34V when the input voltage is between 7V and 28V. DC2247A comes with low EMI features including optimized layout, SSFM, and input and output filters. It passes CISPR 25 class 5 conducted and radiated EMI. The LT3922 is protected against both open and short LED conditions and reports these faults. It also includes thermal shutdown.

DC238A: Demo Board for the LT1506 4.5A, 500kHz Step-Down Switching Regulator.

Demonstration circuit 2779A is an 8V, 16A synchronous step-down Silent Switcher® 2 with spread spectrum frequency modulation featuring the LT8644S. The demo board is designed for 1.2V output from a 2.7V to 8V input. The LT8644S is a compact, ultralow emission, high efficiency, and high speed synchronous monolithic stepdown switching regulator. The integrated bypass capacitors optimize all the fast current loops and make it easier to minimize EMI emissions by reducing layout sensitivity. Selectable spread spectrum mode further improves EMI performance, making it perfect solution to the noise sensitive applications. Peak current mode control with minimum on-time of as low as 20ns allows high step-down conversion even at high frequency. The LT8644S switching frequency can be programmed either via an external resistor or an external clock over a 300kHz to 3.5MHz range. The default frequency of demo circuit 2779A is 2MHz. The SYNC/MODE pin on the demo board DC2779A is grounded (JP1 at BURST position) by default for low ripple Burst Mode® operation. It can be configured into different operation modes through JP1 and SYNC terminal (Table 1 in the demo manual). Figure 4 in the demo manual shows the efficiency of the circuit at 3.3V input and 5V input in force continuous mode operation (input from VIN terminal). To get accurate efficiency measurement, measure the input voltage at the VIN_SENSE/GND terminals and measure the output voltage at the VOUT+ SENSE/VOUT– SENSE terminals. Figure 5 shows the LT8644S temperature rise on DC2779A demo board at 3.3V input and 5V input in forced continuous mode. The LT8644S is assembled in a 4mm × 4mm LQFN package with exposed pads for low thermal resistance. The rated maximum continuous load current is 16A, while derating may be necessary for certain input voltage and thermal conditions. The demo board has an EMI filter installed. This EMI filter can be included by applying the input voltage at the VEMI terminal. The EMI performance of the board (with EMI filter) is shown on Figure 6 in the demo manual. The red lines in EMI Performance are CISPR25 Class 5 limits. The figure shows that the LT8644S circuit passes the test with a wide margin. To achieve EMI performance as shown in Figure 6, the input EMI filter is required and the input voltage should be applied to VEMI terminal, and the test setup can be referred to the CISPR25 standards. If the input is applied to VIN terminal, the EMI filter is bypassed. The LT8644S data sheet gives a complete description of the part, the operation and application information. The data sheet must be read in conjunction with the demo manual for demo circuit 2779A. The layout recommendations for low EMI operation and maximum thermal performance are available in the data sheet section Low EMI PCB Layout and Thermal Considerations. Contact ADI applications engineer for support.

DC2985A is a multi-output power management solution demonstration circuit, featuring the LT3380. It contains two 2.5A, two 1.5A synchronous step-down DC/DC regulators and three 300mA LDO regulators. All regulators can be enabled with external enable pins. After the first regulator is enabled, the remaining enable pins use a precision threshold to allow hardwire-programmed Power-Up Sequence. A micro-USB communication interface is integrated on board to allow software GUI to write or read the registers in LT3380 via its I2C serial port. This GUI can control regulator enables, power-down sequencing, output voltage levels, dynamic voltage scaling, operation modes, status reporting and other special functions. Refer to LT3380 data sheet for more details on the electrical specifications and the setting of its command registers.

Evaluation circuit EVAL-LT8333-AZ features the LT8333 in a SEPIC configuration. It operates with a switching frequency of 2MHz and is designed to convert a 3V to 26V source to 12V output. The converter can output up to 1.25A depending on the input voltage (see Figure 3 in the demo manual, maximum output current vs VIN curve). This evaluation circuit features Spread Spectrum Frequency Modulation (SSFM) and EMI filters to provide optimum EMI performance. This PCB layout is optimized for good EMI performance and small solution size. The evaluation board contains a selectable jumper, JP1, to aid in the selection of the desired SYNC pin mode of operation. At light load, either pulse-skipping (PULSE SKIP) or low-ripple Burst Mode® operation (BURST) can be selected to improve the efficiency. The LT8333 boost/SEPIC/inverting converter IC operates over an input range of 2.8V to 40V, suitable for automotive, telecom, and industrial applications. The converter provides adjustable and synchronizable operation from 300kHz to 2MHz with SSFM option. The LT8333 packs other popular features such as soft-start, bias pin, input undervoltage lockout. The IC can exhibit a low quiescent current down to 9μA in BURST mode and 1μA in shutdown, which makes it ideal for battery-operated systems. The LT8333 is assembled in a thermally enhanced 10-lead 3mm × 3mm DFN package. The data sheet gives a complete description of the device, operation, and application information. The data sheet must be read in conjunction with the demo manual for EVAL-LT8333-AZ.

Power-Distribution Switch with Adjustable Current-Limit Evaluation Module for TPS2552DBV1EVM-364

TPS22913B Ultra-Small, Low Ron, 2A Single-Channel Load Switch Evaluation Module

TPS630250 QFN 4A Switch Buck-Boost Regulator Evaluation Module

20 Volt Simple Switcher® Module 8A Current Sharing Evaluation Board

Ultra Small High Voltage 1A Buck Switching Regulator with Intelligent Current Limit Evaluation Board

High Voltage Monolithic Two-Switch Forward Isolated DC-DC Converter Evaluation Board

SIMPLE SWITCHER® Synchronous 1MHz 2.5A Step-Down Voltage Regulator Evaluation Module

SIMPLE SWITCHER Power Converter High Efficiency 1A Step-Down Voltage Regulator Evaluation Module

LM22679 5A SIMPLE SWITCHER Regulator w/ Adj Soft-Start and Switching Frequency EVM

Simple Switcher® Extended Temp Power Module 5.5Vin; 5A Eval Board

Evaluation Module for BQ24640 Multi Cell Synchronous Switch-Mode Charger

Ultra Small 1.25A Step-Down Switching Regulator with Intelligent Current Limit