The LTC2686 is an 8-channel, 16-bit, ?15 V digital-to-analog converter (DAC) with an integrated precision reference. The LTC2686 is guaranteed monotonic and has built in rail-to-rail output buffers that can source or sink up to 55 mA. This SoftSpan? DAC offers five output ranges up to ?15 V. The range of each channel is independently programmable.The internal 4.096 V precision reference sets the accuracy of the output voltage. An external reference can be used for additional range options. Three toggle pins support Input Register A and Input Register B toggle or sinusoidal dither at multiple frequencies. An analog multiplexer simplifies measurement of pin voltages, load currents, and junction temperature.Programmable offset and gain registers improve the accuracy of the DAC outputs.The serial peripheral interface (SPI) and MICROWIRE?-compatible, 3-wire serial interface operates on logic levels as low as 1.71 V and clock rates up to 50 MHz.APPLICATIONS Optical networking Instrumentation Data acquisition Automatic test equipment Process control and industrial automation

DC2909A showcases the LTC4284 high power, negative hot swap controller with telemetry and EEPROM in a –48V, 31A (1500W) application. DC2909A is configured for parallel mode, which offers reliable low cost hot plug solution for high power systems where input steps are imminent. Included on board is isolation for power good control pins, to enable downstream power converters. LEDs indicate the presence of –48V input and output as well as the state of both supply feeds and power good signaling. High voltage layout rules are followed throughout for best long-term product reliability. Headers are provided for three I2C interfaces, providing instant access to voltage, current, power, energy, fault log, and board temperature data.

The LTC4238 is a high voltage high current Hot Swap controller that allows a board to be safely inserted and removed from a live backplane. Dual 12V gate drive is well suited for high power applications to either share safe operating area across parallel MOSFETs or support a 2-stage start-up that first charges the load capacitance followed by enabling a low on-resistance path to the load.The device features active current limiting (ACL) with two foldback options as VDS increases. The constant power profile limits the power dissipation to be no higher than a fixed value, while the high power profile allows the part to ride through large input steps during operation.The LTC4238 notifies when output power is good. In addition, it has protection features that respond to input undervoltage, overvoltage; and generate a fault when there is an overcurrent or FET bad condition.Applications Live Board Insertion in 12V, 24V and 48V Systems Industrial High Side Switch/Circuit Breaker Computers, Servers Vehicle Electrical Systems

The LTC4238 is a high voltage high current Hot Swap controller that allows a board to be safely inserted and removed from a live backplane. Dual 12V gate drive is well suited for high power applications to either share safe operating area across parallel MOSFETs or support a 2-stage start-up that first charges the load capacitance followed by enabling a low on-resistance path to the load.The device features active current limiting (ACL) with two foldback options as VDS increases. The constant power profile limits the power dissipation to be no higher than a fixed value, while the high power profile allows the part to ride through large input steps during operation.The LTC4238 notifies when output power is good. In addition, it has protection features that respond to input undervoltage, overvoltage; and generate a fault when there is an overcurrent or FET bad condition.Applications Live Board Insertion in 12V, 24V and 48V Systems Industrial High Side Switch/Circuit Breaker Computers, Servers Vehicle Electrical Systems

DC296A Demo Board for: LT1361 Dual and Quad 50MHz, 800V/µs Op Amps LT1210 1.1A, 35MHz Current Feedback Amplifier (CFA)

DC297A: Demo Board for LT1270 8A and 10A High Efficiency Switching Regulators.

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.

The LTC2986 measures a wide variety of temperature sensors and digitally outputs the result, in ?C or ?F, with 0.1?C accuracy and 0.001?C resolution. The LTC2986 can measure the temperature of virtually all standard (Type B, E, J, K, N, S, R, T) or custom thermocouples, automatically compensate for cold junction temperatures and linearize the results. The device can also measure temperature with standard 2-, 3-, or 4-wire RTDs, thermistors, and diodes. The LTC2986 includes excitation current sources and fault detection circuitry appropriate for each type of temperature sensor.The LTC2986/LTC2986-1 are 10-channel software and pin-compatible versions of the 20-channel LTC2983/LTC2984. Additional features include special modes that enable easy protection in universal multi-sensor applications, custom tables for generic ADC readings, and direct temperature readout from active analog temperature sensors. The LTC2986-1 is the EEPROM version of the LTC2986.Applications Direct Thermocouple Measurements Direct RTD Measurements Direct Thermistor Measurements Custom Sensor Applications

Demonstration circuit 2524A is optimized for evaluation of the LTC5555 programmable gain downconverting mixer. The IC incorporates an active mixer and a digital IF VGA with 15.5dB gain control range. The IF gain is programmed in 0.5dB steps through the SPI or parallel interface. The LTC5555 has single-ended 50Ω RF input, single-ended or differential-drive LO input, and differential IF output. It features an enable pin for fast turn-on and shutdown. A reduce power mode is also available through SPI or a CMOS logic pin reducing the total current consumption by approximately 25%. Demonstration circuit 2524A’s RF input port is 50Ω matched from 2.6GHz to 6.4GHz and can be easily tuned down to 1.5GHz or up to 7GHz. The LO port is 50Ω matched from 500MHz to 7GHz. The demo circuit’s differential IF outputs has 100Ω differential impedance and are match for 115MHz to 495MHz IF frequencies. The IF outputs can be modified for other IF frequencies or impedances. Transformer footprint pads are included on the PCB allowing the use of IF transformer to provide 50Ω single-ended IF output. See data sheet for more details on input and output impedance matching. CAUTION: This part is sensitive to electrostatic discharge (ESD). Observe proper ESD precautions when handling the LTC5555.