This circuit uses a parallel-to-series topology that dynamically adjusts LED load voltage as the instantaneous bridge output voltage varies. While a switch-mode power supply such as a buck converter reconfigures the input voltage to match the load, this circuit reconfigures the load to match the input voltage. When the instantaneous input voltage is relatively low, the LEDs are configured in parallel. When the instantaneously input voltage is relatively high, the LEDs are configured in series.

The circuit is designed for input voltages between 100 VAC and 140 VAC . ON Semiconductor CCRs are used to provide constant LED current and to protect LEDs from over-voltage conditions. The circuit employs an additional CCR (shown as CCR2) to increase LED current at high voltages for improved efficiency, PF, and THD performance.

The Dual Stepper Motor Driver Shield Evaluation Board evaluates the AMIS30543, a microstepping stepper motor driver for bipolar stepper motors. It has an on chip voltage regulator, reset output and watchdog reset able to supply peripheral devices. The chip is connected through IO pins and a SPI interface with an external microcontroller that is regulated through the PCA9655E's 16 bits of General Purpose parallel Input and Output (GPIO) expansion.

The AMIS-30543 is a micro-stepping stepper motor driver for bipolar stepper motors. The chip is connected through I/O pins and an SPI interface with an external microcontroller. It has an on chip voltage regulator, reset?output and watchdog reset, able to supply peripheral devices. AMIS-30543 contains a current?translation table and takes the next micro?step depending on the clock signal on the "NXT" input pin and the status of the "DIR" (=direction) register or input pin.

The chip provides a so-called "speed and load angle" output. This allows the creation of stall detection algorithms and control loops based on load-angle to adjust torque and speed. It is using a proprietary PWM algorithm for reliable current control. The chip is fully compatible with the automotive voltage requirements. The AMIS-30543 is ideally suited for general-purpose stepper motor applications in the automotive, industrial, medical, and marine environment. With the on-chip voltage regulator it further reduces the BOM for mechatronic stepper applications.

Evaluation Board developed for 1ED44176N01F - EiceDRIVER™ 25 V low-side gate driver with integrated over-current protection (OCP) and enable/ fault output indication. The board contains one comparator, which is designed as a pulse generator, and one 1ED44176N01F to drive a SOT235-package MOSFET switch connected with an adjustable resistance load (potentiometer-R3).The MOSFET controls the turn-on or turn-off of the resistance load. Rotating the potentiometer, changes the loop current when the MOSFET is on, then gets the different voltage on the shunt resistor (R7). The two LEDs on the board show the different working status of 1ED44176N01F. If the green LED lights up, the 1ED44176N01F is working in normal operation mode. If the red LED lights up, the 1ED44176N01F is in fault condition mode.

EVAL-1ED44176N01F is available from Infineon in sampling quantities.

110 W / 54 V Power Supply Demo Board using ICL5101

in PFC & LLC Topology

High efficiency, high PF, low iATHD and very stable output voltage with low ripple at whole power range are the key features of this demonstration board, which makes it very suitable to be used as a primary power supply for low power systems, such as LED lighting. Its compact design and low BOM cost is due to Infineon IC ICL5101 (CritCM PFC and resonant block are integrated together), which is used as main controller here. With this highly integrated smart IC, the circuit design is dramatically simplified, which results space and BOM cost saving. Furthermore, numerous monitor and protection features ensure highest reliability. Link to ICL5101

• Input voltage range: 85–305 V _AC
• Input voltage frequency: 47–63 Hz
• Regulated main output voltage: 54 V _DC / 2.06 A
• Efficiency at nominal load: ? 93.5% at 230 V _AC
• Input current THD: < 10% @ P _OUT > 40 Wat 230 V _AC
• Harmonics: According to EN61000-3-2 Class-D
• EMI: According to EN55015
• Safety : According to EN61347-2-13
• Board dimensions: 227.3mm(L) x 48.25mm(W) x 30mm(H)

60W 16V SMPS Evaluation Board with F3 controller ICE3BS03LJG

Universal input power supply designed in a 16V 60W off line flyback converter that utilizes the F3 controller ICE3BS03LJG. The application board is operated in discontinuous current mode and running at 65 kHz switching frequency. It has one output voltage with secondary side control regulation. The ICE3BS03LJG is a current mode PWM controller. With the 500V startup cell, active burst mode and BiCMOS technologies, the standby power can be <100mW at no load. The frequency jitter mode and the soft gate drive can give a low EMI performance. The built-in 20ms blanking window and the extendable blanking time concept can prevent the IC from entering the auto restart mode due to over load protection unintentionally. The outstanding propagation delay compensation feature can allow a very precise current limit between low line and high line. For this IC, it provides both auto-restart and latch off protection mode. For those serious faults such as Vcc over-voltage, over temperature, short transformer winding, etc, the IC will enter the latched off protection mode. For the less severe case such as the over load, open loop, short opto-coupler, etc, it enter the auto restart protection mode. In case it needs customer defined protection, the external latch off enable feature can fulfill the requirement.

• 500V Startup Cell
• Active Burst Mode for lowest Standby Power
• Fast load jump response in Active Burst Mode
• 65kHz internally fixed switching frequency
• Frequency jitter and soft gate driving for low EMI
• Max Duty Cycle 75%
• Overall tolerance of Current Limiting < ±5%
• Internal PWM Leading Edge Blanking
• BiCMOS technology provide wide VCC range
• Built-in Soft Start
• Built-in blanking window with extendable blanking time for short duration high current
• Built-in latched Off Protection Mode for Over temperature, Over Voltage & Short Winding
• Auto Restart Protection Mode for Over load, Open Loop & VCC Undervoltage
• External latch enable function

The STEVAL-IHT003V2 evaluation board represents an innovative solution patented by STMicroelectronics to reduce the power losses caused by positive temperature coefficient (PTC) resistors in compressor starter circuits.

The solution features an ACST6 AC switch device to turn off the PTC current after motor start-up; note that the traditional PTC is still used in the electronic starter circuit as it increases circuit safety for AC switch short-circuits or diode mode failure (ref. EN60335-1).

The design reduces starter standby losses from (typ.) 2.5 W to 380 mW for 230 V applications, or 2.5 W to 40 mW for 100 V applications.

Before using the board with a compressor, the PTC behavior must be checked (especially VPTC1 and VPTC2 levels) and different R4 resistor values may be required.

This circuit uses active switching to change how the load is being driven. The LED load will either be driven from the capacitor, C1, discharging, or directly from the AC source. The CCR ensures a constant current through the LED throughout all modes of operation. The switching point of the circuit may be changed by varying the resistor, R1. Changing this switching point will change the amount of time the capacitor is charging. If a higher power output is desired a higher current CCR can be used and the switching point will need to be changed. A metal oxide varistor and fuse are designed into the circuit for surge protection purposes.