Demonstration circuit DC2857A is a 36V 2A synchronous 2MHz boost LED driver featuring the LT3922-1. It drives a single string of LEDs at 330mA up to 34V when VIN is between 7V and 28V. It runs down to 4VIN with reduced ILED and can withstand VIN as high as 36V, but has overvoltage lockout (OVLO) set for 28V for this application. DC2857A runs at 2MHz switching frequency. Spread spectrum frequency modulation (SSFM) can be turned on with a simple jumper, reducing EMI. DC2857A comes with low EMI features including optimized layout, SSFM and input EMI filter. It passes CISPR 25 class 5 conducted and radiated EMI. It is protected against both open and short LED conditions and reports the faults. The LT3922-1 has an input voltage range from 2.8V to 36V. Its internal synchronous 2A 40V switches allow up to 34V of LEDs on the output with room for over voltage protection and overshoot during an open LED event. It has adjustable switching frequency between 200kHz and 2.5MHz. It can be synchronized to an external source or programmed with SSFM for low EMI. The PWMTG highside PWM MOSFET driver assists with short-circuit protection and versatility. LT3922-1 can be configured as a boost, boost-buck, or buck mode LED driver and maintain all of its low EMI, PWM dimming, and fault diagnostic features. The LT3922-1 can be PWM dimmed with an external PWM signal or an internally-generated PWM signal. DC2857A has a jumper that can be set to switch between internallygenerated PWM signal, externally-generated PWM signal, and no PWM signal (100% on). It can be analog dimmed with a control voltage on its control pin (CTRL). When run with both PWM dimming and spread spectrum, the spread spectrum aligns itself with the PWM signal for flicker-free operation. Small ceramic input and output capacitors are used to save space and cost. The board is designed with tiny, high frequency capacitors on both sides of the VOUT pins for a reduction in radiated EMI. The open LED overvoltage protection uses the IC’s constant voltage regulation loop to regulate the output to approximately 37.5V if the LED string is opened, although it may reach almost 40V peak during transient from running LEDs to open. There is a protection diode from LED+ to GND to prevent negative ringing during a short-circuit. The output current can be monitored through the ISMON output pin. Undervoltage and overvoltage lockout can be adjusted on the circuit with a few simple resistor choices. There is an EMI filter on the input of DC2857A. Please follow the recommend layout and four-layer thickness of DC2857A for low EMI applications. The LT3922-1 data sheet gives a complete description of the part, operation and applications information. The LT3922EUFD-1 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.

Demonstration circuit 2881A-A is a 2-phase dual-output, high efficiency, high density, synchronous buck converter with 7V to 14V input range. Each output can supply up to 30A maximum load current with 1V output. The demo board features the LTC3884-1 controller paired with the LTC7050 dual smart power stage to provide a 2-phase buck converter solution. The LTC3884-1 is a dual output poly phase step-down controller with digital power system management. The LTC7050 is a dual monolithic smart power stage which integrates high speed drivers with low resistance half-bridge power switches plus comprehensive monitoring and protection circuitry in an electrically and thermally optimized package. Please refer to the LTC3884-1 and LTC7050 data sheet for more detailed information. DC2881A-A powers up to default settings and produces power based on configuration resistors (or with the setting in its non-volatile memory) without the need for any 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 and store the configuration in EEPROM, view telemetry of voltage, current, temperature and fault status.

Demonstration circuit 2896A-B demonstrates a high power boost converter and features the LT®8551 the phase expander with internal gate drivers. The DC2896A-B employs LTC3769, a single-phase boost controller as primary controller and LT8551 as the phase expander which added four more power phases. The increased number of power sections connected to the LT8551, results in greater higher level output power without a corresponding increase in the difficulty of the design or a sacrifice of primary controller LTC3769 features. The input voltage range of DC2896A-B is from 10V to 46V and the output is 48V. The maximum input current is 12A per power section, so the maximum input current of DC2896A-B is 60A. It’s reflected to 30A of output current and output power of 1,440W at an input voltage of 24V. Correspondingly output current will drop to 14.5A and output power will to 720W at a 12V input voltage, to keep the input current at the same level of 60A. Both values will increase at higher voltages. The input current value can be increased above 60A, if heat sinks are installed, see parts list below. The switching frequency is 250kHz and at a 24V input to 48VOUT at full load, the efficiency of DC2896A-B is 98%. As the input voltage decreases, the output current should be decreased as well, to prevent saturation of the DC2896A-B inductors, the derating curve presented on Figure 3. Efficiency curves presented on Figure 4. DC2896A-B resistors R114 to R119 program the phase relationship between the power sections, by setting the Total Distinct Phase Number (TDPN). For increasing efficiency and reducing switching losses at light loads DC2896A-B supports disconnecting some power sections. This mode of operation designated as the stage shedding and it is programed by the jumper J3 STAGE SHED. Jumper JP1 programs the LT8551 SYNC pin and it allows DC2896A-B to be synchronized to an external clock. The print circuit board of DC2896A also supports two phase expander controllers, the LT8561 and LT8551, with versions DC2896A-A and DC2896A-B correspondingly. The table [1] in the electrical schematic describes differences between both versions, including controller biasing and gate drive voltages. DC2896A-B has jumper SHDN (JP2) for manually enable or disable controller. The SYNC (E19) input can be used to sync LT8551 with an external signal. There are also terminals that make it easy to monitor the control logic of the LT8551 functional. The current sense resistors RSNS1 to RSNS5 used for implementation of current mode control, monitoring and sharing current between the phases. To further increase efficiency DC2896A-B supports optional DCR sensing of inductors L1 to L5. DC2896A-B includes sense line filters and filter options for inputs to the LT8551 in accordance with data sheet recommendations. Undervoltage shutdown, switching frequency and LT8551 ILIM current limit levels can all be adjusted by resistors or resistor jumpers. DC2896A-B comes with a housekeeping circuit based on U3 controller. It reduces the power dissipation that would otherwise occur at high input voltages in regulator transistor Q21. The housekeeping circuit also stabilizes converter biasing at sudden input voltage drops. A high level of available output power without a corresponding high level of design complexity makes the LT8551 attractive for high power DC bus and battery systems in commercial, industrial and automotive settings. DC2896A-B features the LT8551EUKG in a thermally enhanced 52-pin 7mm × 8mm QFN package. The LT8551 and LTC3769 data sheets must be read in conjunction with this demo manual to properly use or modify DC2896A-B.

Demonstration circuit 2897A is a low IQ, triple output, synchronous step-down supply featuring the LTC7819. The circuit is optimized for high efficiency. It provides outputs of 3.3V at 12A, 8.5V at 10A and 5.0V at 12A over an input voltage range of 10V to 36V with a switching frequency of 380kHz. Each rail uses a 3mΩ sense resistor to sense the current and provides optional footprints for DCR sensing. Typical applications include automotive, transportation, industrial, military and avionics systems. Features of the DC2897A include pin selectable light load operating modes of forced continuous mode, pulse-skipping and Burst Mode® operation. Optional spread spectrum modulation to reduce EMI, a PLLIN pin to synchronize to an external clock, optional DCR sensing footprints, an EXTVCC pin to reduce losses in the controller and optional footprints to parallel two or three channels. The LTC7819 data sheet provides a complete description of the part, operational details, and applications information. DC2897A must be read in conjunction with the data sheet.

Demonstration circuit DC290 is a constant-frequency step-down converter using an LTC1877 or an LTC1878 monolithic synchronous regulator. The LTC1878 has an input voltage range of 2.65V < VIN < 6V and the LTC1877 has an input voltage range of 2.65V < VIN < 10V. The LTC1878 is optimized for low voltage operation and is ideally suited for single Li-Ion cell or 3-NiCd/NiMH cell applications. The LTC1877, with its higher voltage capability, is ideally suited for two Li-Ion cells or 4- to 6-NiCd/NiMH cell applications.

Demonstration circuit 2918A is a 42V, 5A synchronous step-down SILENT SWITCHER with spread spectrum frequency modulation featuring the LT8636. The demo board is designed for 5V output from a 5.8V to 42V input. The wide input range allows a variety of input sources, such as automotive batteries and industrial supplies. The LT8636 is a compact, low emission, high efficiency, and high frequency synchronous monolithic step-down switching regulator. The proprietary silent switcher architecture minimizes electromagnetic emissions with simplified filter and reduced layout sensitivity. Selectable spread spectrum mode further improves EMI performance, making it perfect solution to the noise sensitive applications. The regulator’s ultralow 2.5μA quiescent current with the output in full regulation enables applications requiring highest efficiency at very light load currents, such as automotive and battery powered portable instruments. Peak current mode control with minimum on-time of as small as 30ns allows high step-down conversion even at high frequency. The LT8636 switching frequency can be programmed either via oscillator resistor or external clock over a 200kHz to 3MHz range. The default frequency of demo circuit 2918A is 2MHz. The SYNC/MODE pin on the demo board 2918A is grounded (JP1 at BURST position) by default for low ripple Burst Mode® operation. To synchronize to an external clock, move the Jump JP1 to SYNC/FCM and apply the external clock to the SYNC terminal on the 2918A. In sync mode, the part runs in forced continuous mode. Without external clock applied, the SYNC/MODE pin is floating, and the part runs in forced continuous mode. This mode offers fast transient response and full frequency operation over a wide load range. Alternatively, move the Jump JP1 to the SPREAD-SPECTRUM, and the SYNC/MODE is tied to INTVCC, the part runs in forced continuous mode with spread spectrum function enabled. To get accurate efficiency measurement, measure the input voltage at the VIN_SENSE and GND terminals, which are Kelvin connected to the input cap C2 through signal traces. The LT8636 is assembled in a 4mmx3mm LQFN package with exposed pads for low thermal resistance. The rated maximum load current is 5A, while derating is necessary for certain input voltage and thermal conditions. The demo board has an EMI filter installed. The red line in Radiated EMI Performance is CISPR25 Class 5 peak limit. The circuit passes the test with a wide margin. To achieve EMI/EMC performance, the input EMI filter is required and the input voltage should be applied at VEMI terminal, and the setup can be referred to the CISPR 25 standards. The LT8636 datasheet gives a complete description of the part, operation and application information. The datasheet must be read in conjunction with this demo manual for demo circuit 2918A. The layout recommendations for low EMI operation and best thermal performance are available in the datasheet section Low EMI PCB Layout and Thermal Considerations and Peak Output Current. Contact ADI applications engineer for support.

The LTC7802 is a high performance dual step-down synchronous DC/DC switching regulator controller that drives all N-channel power MOSFET stages. Constant frequencycurrent mode architecture allows a phase-lockable switching frequency of up to 3MHz. The LTC7802 operates from a wide 4.5V to 40V input supply range. Power loss and supply noise are minimized by operating the two controller output stages out-of-phase.The very low no-load quiescent current extends operating runtime in battery powered systems. OPTI-LOOP compensation allows the transient response to be optimizedover a wide range of output capacitance and ESR values. The LTC7802 features a precision 0.8V reference and power good output indicators. The MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current mode at light loads.The LTC7802 additionally features spread spectrum operation which significantly reduces the peak radiated and conducted noise on both the input and output supplies, making it easier to comply with electromagnetic interference (EMI) standards.APPLICATIONSAutomotive and TransportationIndustrialMilitary/Avionics

The ADF7024 is an ultralow power, integrated transceiver for use in the license-free ISM bands at 433 MHz, 868 MHz, and 915 MHz. Its ease of use and high performance make it suitable for a wide variety of wireless applications. The ADF7024 is suitable for operation under the European ETSI EN 300-220 regulation, the North American FCC Part 15 regulation, and other similar regulatory standards.The ADF7024 can operate under a number of predefined radio profiles. For each radio profile, optimized register settings are provided for the ADF7024 radio. This ensures that the RF communication layer works seamlessly, allowing the user to concentrate on the protocol and system level design and prototyping. The radio profiles cover common data rate and modulation options. There are six radio profiles in total, as shown in Table 1.The ADF7024 operates with a power supply range of 2.2 V to 3.6 V and has very low power consumption in both Tx and Rx modes, enabling long lifetimes in battery-operated systems while maintaining excellent RF performance.The low IF receiver minimizes power consumption and provides excellent sensitivity. The receiver is exceptionally linear and, therefore, is very resilient to the presence of interferers in spectrally noisy environments. The highly efficient transmitter has programmable output power up to 13.5 dBm and automatic power amplifier (PA) ramping to meet transient spurious specifications. The RF synthesizer comprises a voltage controlled oscillator (VCO), a low noise fractional-N phase-locked loop (PLL) and a loop filter, all of which are fully integrated and automatically calibrated. This agile frequency synthesizer facilitates the implementation of frequency-hopping spread spectrum (FHSS) systems.The smart wake mode (SWM) allows the ADF7024 to wake up autonomously from sleep using the internal wake-up timer without intervention from the host processor. This functionality allows carrier sense, packet sniffing, and packet reception while the host processor is in sleep, thereby reducing overall system current consumption.The ADF7024 eases the processing burden of the host processor by integrating the lower layers of a typical communication protocol stack. The host processor can configure the ADF7024 using a simple command-based protocol over a standard 4-wire SPI interface. A single-byte command transitions the radio between states or performs a radio function.A complete wireless solution can be built using a small number of external discrete components and a host processor (typically a microcontroller).For more information, see the ADF7024 Hardware Reference Manual, UG-698, which is only available as part of the ADF7024 design resource package.APPLICATIONS Wireless sensor networks (WSNs) Home and building automation Asset tracking Process and building control Industrial control Internet of Things (IoT)

The ADF7241 is a highly integrated, low power, and high performance transceiver for operation in the global 2.4 GHz ISM band. It is designed with emphasis on flexibility, robustness, ease of use, and low current consumption. The IC supports the IEEE 802.15.4-2006 2.4 GHz PHY requirements in both packet and data streaming modes. With a minimum number of external components, it achieves compliance with the FCC CFR47 Part 15, ETSI EN 300 440 (Equipment Class 2), ETSI EN 300 328 (FHSS, DR > 250 kbps), and ARIB STD T-66 standards.The ADF7241 complies with the IEEE 802.15.4-2006 2.4 GHz PHY requirements with a fixed data rate of 250 kbps and DSSS-OQPSK modulation. The transmitter path of the ADF7241 is based on a direct closed-loop VCO modulation scheme using a low noise fractional-N RF frequency synthesizer. The automatically calibrated VCO operates at twice the fundamental frequency to reduce spurious emissions and avoid PA pulling effects. The bandwidth of the RF frequency synthesizer is automatically optimized for transmit and receive operations to achieve best phase noise, modulation quality, and synthesizer settling time performance. The transmitter output power is programmable from ?20 dBm to +4 dBm with automatic PA ramping to meet transient spurious specifications. An integrated biasing and control circuit is available in the IC to significantly simplify the interface to external PAs.For more information, please refer to the data sheet.Applications Wireless sensor networks Automatic meter reading/smart metering Industrial wireless control Healthcare Wireless audio/video Consumer electronics ZigBee

The ADFS5758 is a single-channel, 16-bit, current/voltage output DAC. The device is functional safety approved for unipolar current output and is a fully compliant item with a systematic capability of SC3, which can be used in safety-related applications up to SIL 2, according to IEC 61508. This arrangement allows a single ADFS5758 to be used to achieve SIL 2 for a nonredundant configuration. The safe state for the ADFS5758 is open circuit/high impedance.The ADFS5758 is a single-channel, voltage and current output digital-to-analog converter (DAC) that operates with a power supply range from ?33 V minimum on AVSS to +33 V maximum on AVDD1 with a maximum operating voltage between the two rails of 60 V. On-chip dynamic power control (DPC) minimizes package power dissipation, which is achieved by regulating the supply voltage (VDPC+) to the VIOUT output driver circuitry from 4.95 V to 27 V using a buck dc-to-dc converter, optimized for minimum on-chip power dissipation. The CHART pin enables a HART? signal to be coupled onto the current output.The device uses a versatile 4-wire serial peripheral interface (SPI) that operates at clock rates of up to 50 MHz and is compatible with standard SPI, QSPI?, MICROWIRE?, DSP, and microcontroller interface standards. The interface also features an optional SPI cyclic redundancy check (CRC) and a windowed watchdog timer. The ADFS5758 offers improved diagnostic features from its predecessors, such as an integrated independent 12-bit diagnostic analog-to-digital converter (ADC) that can be used to digitize both internal and external nodes.Product HighIights Functional safety approved to SIL 2/SC3 by T?V Rheinland. Range of advanced diagnostic features, including an integrated ADC for high reliability. DPC using an integrated buck dc-to-dc converter for thermal management. When used with the ADP1031, the ADFS5758 enables eight channel to channel isolated outputs at <2 W dissipated power. Programmable power control (PPC) mode to enable faster settling time (15 ?s typical). Highly robust with output protection from miswire events (?38 V). Applications Process control Actuator control Channel isolated analog outputs Programmable logic controller (PLC) and distributed control system (DCS) applications HART network connectivity