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

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

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 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.

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

DC427B-A: Demo Board for the LTC1966 Precision Micropower, Delta Sigma RMS-to-DC Converter.

DC489A-A: Demo Board for the LTC5507 100kHz to 1GHz RF Power Detector.

Demonstration circuit DC675C is for the evaluation of filter circuits using an LT1568. The LT1568 is a dual 2nd order active-RCfilterbuildingblockwithprecision ±0.75% capacitors and low noise op amps with 180MHz GBW trimmed to ±10% maximum variation. The ±10% GBW variation of the LT1568 op amps allows for minimizing the higher frequency error by decreasing resistor values. The cutoff or center frequency (fC) range of an LT1568 filter is 200kHz to 10MHz (5MHz for a bandpass filter). The low limit of 200kHz was chosen only to minimize resistor noise and DC offsets (using external capacitors the fC frequency can be less than 200kHz). For testing and evaluation, the DC675C assembly is configured as a single 4th order, 500kHz narrow passband bandpass filter. For other possible LT1568 configurations, the DC675C has unused pads for 0805 surface mount resistors and capacitors preconfigured with PCB traces to allow for the following high accuracy LT1568 filter circuits: 4th order lowpass filter 5th order lowpass filter 4th order narrow passband bandpass 4th order wide passband bandpass 4th order highpass filter Refer to the LT1568 data sheet for additional information about filter circuit configurations.