Demonstration circuit 2989A features the LTM4657 µModule® regulator, a high performance, high efficiency step-down regulator. The LTM4657 is a complete DC/DC point-of-load regulator in a thermally enhanced 6.25mm x 6.25mm x 3.87mm BGA package. The LTM4657 has an operating input voltage range of 3.1V to 20V and provides an output current up to 8A. The output voltage is programmable from 0.6V to 5.5V and can be remotely sensed. The stacked inductor design improves thermal dissipation and significantly reduces the package area.  Output voltage tracking is available through the TRACK/SS pin for supply rail sequencing. External clock synchronization is available through the SYNC/MODE pin. For high efficiency at low load currents, select DCM mode operation using the MODE jumper (JP7) in less noise sensitive applications. The LTM4657 data sheet must be read in conjunction with this demo manual for working on or modifying DC2989A.

Demonstration circuit 2991A features the LTC3308A 5V, 4A synchronous step-down Silent Switcher® operating as a 2.0MHz, 3.3V to 1.2V 4A buck regulator. The LTC3308A supports adjustable output voltages from 0.5V to VIN with operating frequencies from 1MHz up to 3MHz. The LTC3308A is a compact, ultralow emission, high efficiency, and high speed synchronous monolithic stepdown switching regulator. A minimum on-time switching of 22ns enables high VIN to low VOUT conversion ratios at high frequencies. The DC2991A operating mode may be selected as BURST, SKIP or Forced Continuous (FC) mode. Setting JP1 to the FC/SYNC position will allow the LTC3308A to sync to a clock frequency from 1MHz to 3MHz. The LTC3308A operates in forced continuous mode when syncing to an external clock. The DC2991A is set to a fixed 2MHz frequency by connecting RT to VIN through a 0Ω resistor, R9. The frequency can be easily changed by removing R9 and setting an appropriate resistor in the R4 location to obtain the desired frequency. Refer to the LTC3308A data sheet for the proper RT value for a desired switching frequency. The DC2991A 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 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 LTC3308A data sheet gives a complete description of the device, operation and application information. The data sheet must be read in conjunction with this demo manual. The LTC3308A is assembled in a 2mm × 2mm LQFN package with exposed pads for low thermal resistance. The layout recommendations for low EMI operation and maximum thermal performance are available in the data sheet section: Low EMI PCB Layout.  The Efficiency vs Load graph shows the efficiency and the power loss of the circuit with a 3.3V input in Burst Mode operation.

Demonstration circuit 2995A is a buck regulator featuring the LTC7891. The DC2995A operates from a 36V to 72V input voltage range and generates a 12V, 20A output. The LTC7891 has a precision voltage reference which can generate an output voltage with 2% tolerance over the full operating conditions. The 500kHz switching frequency operation results in a small and efficient circuit. The converter achieves over 96% efficiency with 20A load. The demonstration circuit can be easily modified to regulate output voltages from 0.8V to 60V. The DC2995A provides a high performance cost-effective solution for generating a 12V output. The LTC7891 data sheet gives a complete description of this part, its operation and application information and must be read in conjunction with the demo manual.

Demonstration circuit 3099A is a 42V, 5A synchronous step-down Silent Switcher® with spread spectrum frequency modulation featuring the LT8640A. The demo board is designed for 5V output from a 5.7V to 42V input. Meanwhile the LT8640A can operate down to 3.4V inputs. The wide input range allows a variety of input sources, such as automotive batteries and industrial supplies. The LT8640A is a compact, ultralow emission, high efficiency, and high speed synchronous monolithic stepdown switching regulator. The integrated power switches and inclusion of all necessary circuitry reduce the components count and solution size. Special Silent Switcher architecture minimizes EMI emissions. Selectable spread spectrum mode can further improve EMI performance. Ultralow 2.5μA quiescent current in Burst Mode® operation achieves high efficiency at very light loads. Fast minimum on-time of 30ns enables high VIN to low VOUT conversion at high frequency. The LT8640A switching frequency can be programmed either via oscillator resistor or external clock over a 200kHz to 3MHz range. The default frequency of demo circuit 3099A is 2MHz. The LT8640A SYNC/MODE pin on the demo board is grounded (JP1 at BURST position) by default for low ripple Burst Mode operation. Spread spectrum mode and forced continuous mode can be selected respectively by moving JP1 shunt. To synchronize to an external clock, move JP1 to FCM/SYNC and apply the external clock to the SYNC terminal. The LT8640A data sheet gives a complete description of the part, operation, and application information. The data sheet must be read in conjunction with this demo manual for demo circuit 3099A. The LT8640A is assembled in a 3mm × 4mm plastic QFN package with exposed pad for low thermal resistance. 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 and Peak Output Current.

Demonstration circuit 3145A demonstrates a high efficiency thermoelectric cooler driver and features the LT8722 monolithic driver. The input voltage range of the DC3145A is from 3.1V to 15V and the output is a SPI programmable differential voltage output. The maximum output current is 4A. The switching frequency SPI programmable from 500kHz to 3MHz. The LT8722 is controlled through an SPI interface and therefore the demonstration circuit is also setup to interface through SPI. For demonstration purposes the manual provides instruction on how to connect the DC2026C Linduino board to monitor and control the DC3145A with a PC using a command line Arduino IDE interface.

DC327A Demo Board for: LTC1545 Software-Selectable Multiprotocol Transceiver LTC1546 Software-Selectable Multiprotocol Transceiver with Termination

DC336A - Demo Board

The LTC1563-2/LTC1563-3 are a family of extremely easy-to-use, active RC lowpass filters with rail-to-rail inputs and outputs and low DC offset suitable for systems with a resolution of up to 16 bits. The LTC1563-2, with a single resistor value, gives a unity-gain Butterworth response. The LTC1563-3, with a single resistor value, gives a unity-gain Bessel response. The proprietary architecture of these parts allows for a simple resistor calculation:R = 10k (256kHz/fC); fC = Cutoff Frequencywhere fC is the desired cutoff frequency. For many applications,this formula is all that is needed to design a filter.By simply utilizing different valued resistors, gain andother responses are achieved.The LTC1563-X features a low power mode, for the lowerfrequency applications, where the supply current is reducedby an order of magnitude and a near zero powershutdown mode.The LTC1563-Xs are available in the narrow SSOP-16package (Same footprint as an SO-8 package).Applications Discrete RC Active Filters and Modules Antialiasing Filters Smoothing or Reconstruction Filters Linear Phase Filtering for Data Communication Phase Locked Loops

Demonstration circuit DC339-B is a low noise micropower voltage regulator using the 300mA output current LT1962 linear regulator in an 8-lead MSOP package. The demo board has an input voltage range from 2.3V to 20V and a jumper-selectable output votlage that can be set to 1.22V, 2.5V, 3.0V, 3.3V, 5V or a user-defined value. The LT1962's low 20µVRMS (10Hz to 100kHz bandwidth) output noise and low 30µA quiescent current make the device ideal for voltage-controlled oscillators, RF power supplies and local regulators in larger systems.

DC355A: Demo Board for the LT1959 4.5A, 500kHz Step-Down Switching Regulator.