Demonstration circuit 2423A showcases the LTM9100 Isolated Switch Controller in either a typical 48V application (–A) or in a high voltage 380V application (–B). The board may be configured for either high side or low side operation, dependent on the connection of external supply and load to the banana jacks. An on board capacitive load may also be wired into the circuit. LEDs indicate the presence of input and output voltage.

Demonstration circuit 2798A is a high voltage, dual-phase single output boost converter with 10V to 16V input range. The output voltage is adjustable from VIN to 48V. And the output can supply a 10A maximum load current. The demo board has a LTC7841 controller, which is a 60V dual-phase single output boost controller with digital power system management. Please see the LTC7841 data sheet for more detailed information. The DC2798A powers up to default settings and produces power based on the command from the serial bus communication. This allows easy evaluation of the DC/DC converter. To fully explore the extensive power system management features of the part, download the GUI software LTpowerPlay® onto your PC and use ADI’s I2C/SMBus/PMBus dongle DC1613A to connect to the board. LTpowerPlay allows the user to reconfigure the part on-the-fly, view telemetry of voltage, current, temperature and fault status.

Demonstration circuit DC2342A is a 60V synchronous boost LED controller featuring the LT®3762. It drives a single string of LEDs at 2A up to 32V when VIN is between 7V and 28V. It runs down to 4VIN with reduced ILED and can withstand VIN transients as high as 30V. DC2342A runs at approximately 300kHz switching frequency. Spread spectrum frequency modulation (SSFM) can be turned on with a simple jumper, reducing EMI. DC2342A is designed for high power step-up LED controller applications that require excellent efficiency across the VIN range. This demonstration circuit is protected against both open and short LED conditions, each having its own flag. The LT3762 has an input range from 2.5V to 42V. It has an adjustable switching frequency between 100kHz and 1MHz. Enabling SSFM spreads the switching frequency from fSW down to fSW – 30% for reduced EMI. SSFM speed is set by placing a capacitor from the SSFM pin of the LT3762 to ground, and can be disabled by shorting this pin to GND. DC2342A has a simple jumper option to enable/disable spread spectrum frequency modulation. The LT3762 can be PWM dimmed with an external PWM signal, as well as an internally generated PWM signal. A capacitor from PWM to GND of the LT3762 sets the PWM frequency, while the PWM duty cycle is determined by the voltage on the DIM terminal. Between 0V and 3V, VDIM gives between 0.4% and 97% PWM duty cycle. DC2342A has a jumper that can be set to switch between internally generated PWM signal, externally generated PWM signal, and no PWM signal (100% on). When run with both PWM dimming and spread spectrum enabled, the spread spectrum aligns itself with the PWM signal for flicker free operation. DC2342A can also be analog dimmed by placing a voltage source at either of its two CTRL turrets. Small ceramic input and output capacitors are used to save space and cost. The open LED overvoltage protection uses the IC’s constant voltage regulation loop to regulate the output to approximately 35.5V if the LED string is opened, although it may reach almost 40V peak during the transient caused by an open circuit. There is a protection diode from LED+ to GND to prevent negative ringing during a short-circuit. Undervoltage lockout can be adjusted on the circuit with a few simple resistor choices. Further modifications can be made to DC2342A to reconfigure the circuit from a boost topology to operate as a buck-mode or buck-boost mode LED driver. Please consult the factory for details. The LT3762 data sheet gives a complete description of the part, operation and applications information. The data sheet must be read in conjunction with this Demo Manual for demonstration circuit DC2342A. The LT3762EUFD is assembled in a 28-lead plastic 4mm × 5mm QFN package with a thermally enhanced ground pad. Proper board layout is essential for maximum thermal performance. See the data sheet section Layout Considerations.

DC1049A: Demo Board for the LTC4264 High Power PD Interface Controller with 750mA Current Limit.

DC362A-A: Demo Board for the LTC1405 12-Bit, 5Msps, Sampling ADC.

DC563A: Demo Board for the LTC2920 Single (-1) & Dual (-2) Margining Controller.

DC756A: Demo Board for the LTC4150 Coulomb Counter/Battery Gas Gauge.

DC852A: Demo Board for the LTC4354 Negative Voltage Diode-OR Controller and Monitor.

Demonstration circuit 1830B is a battery charger controller and PowerPath™ manager featuring the LTC4000. This board should be connected to a front end DC/DC power supply for a complete charger solution.

Demonstration circuit 2278A features the LTC4281 hot swap controller. The LTC4281 is well suited to high power applications because the precise monitoring capability and accurate current limiting reduces the extremes in which both loads and power supplies must safely operate. Non-volatile configuration allows for flexibility in the autonomous generation of alerts and response to faults.