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.

Demo board DC2783A features the LT3040, a 200mA high performance, robust voltage reference/DAC buffer. LT3040 has ultralow output noise, ultrahigh power supply rejection ratio (PSRR) and low dropout voltage for powering noise sensitive, high accuracy systems. DC2783A has two inputs: V+ and VIN. V+ supplies power to the buffer, operating over a range from 2V to 20V. VIN is the regulation set-point for the output with a range from 0V to 15V. Current limit is programmable by connecting a resistor, R3, from ILIM to GND. The ILIM can also serve as a current monitor pin with a range from 0V to 300mV. LT3040 has fast start capability. Connecting FS pin across an input low pass filter resistor, R2, fast starts the LT3040. Fast start circuitry is typically triggered active if VFS − VIN ≥ 100mV and stays active until VFS – VIN ≤ 7mV. If fast start functionality is not needed, connect FS to VIN by setting R2 to 0Ω and applying the input voltage at FS. LT3040 has a fault flag to indicate faults at the output. Built-in protection includes reverse battery protection, reverse current protection, internal current limit with foldback and thermal limit with hysteresis. The LT3040 datasheet gives a complete description of the part, operation and applications information. The datasheet must be read in conjunction with this Demo Manual for demonstration circuit DC2783A. The LT3040 is assembled in a 12-lead MSOP and a 10-lead (3mm x 3mm) plastic DFN package with an exposed pad on the bottom-side of the IC. Proper board layout is essential for maximum thermal performance.

Demonstration circuit 2785A-A features the LTM4668 µModule® regulator, a Quad 1.2A high efficiency step-down regulator. DC2785A-A has an operating input voltage range of 2.7V to 17V and can provide an output current of up to 1.5A. The output voltage can be programmed from 0.6V up to 1.8V. The LTM4668 is a complete DC/DC point of load regulator in a thermally enhanced 6.25mm × 6.25mm × 2.1mm BGA package requiring only a few input and output capacitors. External clock synchronization is available through the CLKIN turret. The LTM4668 data sheet must be read in conjunction with this demo manual for working on or modifying demo circuit 2785A-A.

Demonstration circuit 2786A is a single output high voltage non-isolated synchronous step-down converter that drives an all N-channel MOSFET power stage. It features the LTC7800, a low quiescent current high frequency (programmable fixed frequency from 320kHz up to 2.25MHz) synchronous step-down DC/DC controller housed in a small 3mm x 4mm QFN package. This DC2786A operates over an input voltage range from 8V to 40V, while the LTC7800 can operate up to 60V. This demo board produces a 3.3V output voltage with up to 10A output current, and is configured with a sense resistor for current sensing. A mode selector allows the DC2786A to operate in forced continuous operation, pulse-skipping or Burst Mode® operation during light loads. The LTC7800 features two integrated 5V gate drivers with 20ns deadtime which is good for GaN transistors or logic-level MOSFETs to maximize efficiency. The EXTVCC pin permits the LTC7800 to be powered from the output of the switching regulator or other available source, reducing power dissipation and improving efficiency. Please refer to the LTC7800 data sheet for a complete description of the part operation and application information.

Demonstration circuit 2788A is a boost LED driver featuring the LT®3950. This demonstration circuit powers a string of LEDs at 330mA. The step-up topology can be used to drive a string of up to 28V of LEDs as assembled. The maximum output voltage capability of the LT3950 is 60V. DC2788A runs from an input voltage range of 6V to 24V as built. It also runs at 2MHz and has the capability to turn on spread spectrum frequency modulation (SSFM) for a frequency range of 2.0MHz to 2.5MHz. Dimming control can be achieved with analog dimming or PWM dimming—either from an external or internally-generated clock source. DC2788A features undervoltage lockout (UVLO) set at 6.6V with a 1.0V hysteresis for turn-on. The UVLO voltage, LED current, output voltage range, switching frequency, brightness control, SSFM, and the topology can all be adjusted with simple modifications to the demonstration circuit. LT3950 is a monolithic 1.5A peak switch current, 60V LED driver. The guaranteed peak switch current rating of the IC is 1.5A and this is important to know when calculating maximum output current at a given LED voltage and input voltage for a boost converter. The LT3950 features SSFM and a well-controlled SW node for low emissions. A frequency range of 200kHz to 2MHz and a high-side PWMTG PWM-dimming MOSFET makes this a very versatile IC for many applications. It can be used for boost, buck-boost mode and buck mode LED driver applications. The PWMTG MOSFET not only provides high PWM dimming ratio capability, but it also serves as a short-circuit protection device. The FAULT flag indicates when there is either a short-circuit or open-LED fault at the output. The demo circuit is designed to be easily reconfigured to suit other applications, including the example schematics in the data sheet. Consult technical support for assistance. High voltage operation, 3V input voltage operation, multiple topologies, small-and-compact size, fault protection, low EMI, and multiple brightness control options make the LT3950 flexible and powerful for compact, noise-sensitive LED driver solutions. The LT3950JMSE featured on this demo circuit is available in a thermally enhanced 16-lead plastic MSOP package. The LT3950 data sheet must be read in conjunction with this demo manual to properly use or modify demo circuit DC2788A.

The 8-bit LTC1665 and 10-bit LTC1660 integrate eight accurate, serially addressable digital-to-analog converters (DACs) in tiny 16-pin narrow SSOP packages. Each buffered DAC draws just 56?A total supply current, yet is capable of supplying DC output currents in excess of 5mA and reliably driving capacitive loads to 1000pF. Sleep mode further reduces total supply current to 1?A.Proprietary, inherently monotonic voltage interpolation architecture provides excellent linearity while allowing for an exceptionally small external form factor.Ultralow supply current, power-saving Sleep mode and extremely compact size make the LTC1665 and LTC1660 ideal for battery-powered applications, while their ease of use, high performance and wide supply range make them excellent choices as general purpose converters.Applications Mobile Communications Remote Industrial Devices Automatic Calibration for Manufacturing Portable Battery-Powered Instruments Trim/Adjust Applications

100 mA Split Rail SWIFT™ Converter Evaluation Module

The ADP2443 is synchronous step-down, dc-to-dc regulator with an integrated 98 m?, high-side power metal oxide semicon-ductor field effect transistor (MOSFET) and a 35 m?, synchronous rectifier MOSFET to provide a high efficiency solution in a compact 4 mm ? 4 mm LFCSP package. The regulators operate from an input voltage range of 4.5 V to 36 V. The output voltage can be adjusted down to 0.6 V and deliver up to 3 A of continuous current. The fast 50 ns minimum on time allows the regulators convert high input voltage to low output voltage at high frequency.The ADP2443 uses an emulated current mode, constant frequency pulse-width modulation (PWM) control scheme for excellent stability and transient response. The switching frequency of the ADP2443 can be programmed from 200 kHz to 1.8 MHz. The synchronization function allows the switching frequency be syn-chronized with an external clock to minimize the system noise.The ADP2443 targets high performance applications that require high efficiency and design flexibility. External compensation and an adjustable soft start function provide design flexibility. The power-good output and precision enable input provide simple and reliable power sequencing.Other key features include undervoltage lockout (UVLO), overvoltage protection (OVP), overcurrent protection (OCP), short-circuit protection (SCP), and thermal shutdown (TSD).The ADP2443 operates over the ?40?C to +125?C operating junction temperature range and is available in a 24-lead, 4 mm ? 4 mm LFCSP package.Applications Intermediate power rail conversion Multicell battery powered systems Process control and industrial automation Healthcare and medical Networking and servers

TPS63010EVM-235 Evaluation Module

TPS65001EVM-453 Evaluation Module