World's most precise clock set for commercial countdown

The world's most precise clock has been fine-tuned to boost radar and GPS capabilities.

The Cryogenic Sapphire Oscillator, or Sapphire Clock, has been enhanced by researchers from the University of Adelaide in South Australia to achieve near attosecond capability.

The oscillator is 10-1000 times more stable than competing technology and allows users to take ultra-high precision measurements to improve the performance of electronic systems.Increased time precision is an integral part of radar technology and quantum computing, which have previously relied on the stability of quartz oscillators as well as atomic clocks such as the Hydrogen Maser.

Atomic clocks are the gold-standard in time keeping for long-term stability over months and years. However, electronic systems need short-term stability over a second to control today's devices.

The new Sapphire Clock has a short-term stability of better than 1x10-15, which is equivalent to only losing or gaining one second every 40 million years, 100 times better than commercial atomic clocks over a second.

The original Sapphire Clock was developed by Professor Andre Luiten in 1989 in Western Australia before the team moved to South Australia to continue developing the device at the University of Adelaide.

Lead researcher Martin O'Connor said the development group was in the process of modifying the device to meet the needs of various industries including defence, quantum computing and radio astronomy.

The 100cm x 40cm x 40cm clock uses the natural resonance frequency of a synthetic sapphire crystal to maintain a steady oscillator signal.

Associate Professor O'Connor said the machine could be reduced to 60 per cent of its size without losing much of its capability.

"Our technology is so far ahead of the game, it is now the time to transfer it into a commercial product," he said.

 "We can now tailor the oscillator to the application of our customers by reducing its size, weight and power consumption but it is still beyond current electronic systems."

The Sapphire Clock, also known as a microwave oscillator, has a 5 cm cylinder-shaped crystal that is cooled to -269C.

Microwave radiation is constantly propagating around the crystal with a natural resonance. The concept was first discovered by Lord Rayleigh in 1878 when he could hear someone whispering far away on the other side of the church dome at St Paul's Cathedral.

The clock then uses small probes to pick up the faint resonance and amplifies it back to produce a pure frequency with near attosecond performance.

"An atomic clock uses an electronic transition between two energy levels of an atom as a frequency standard," Associate Professor O'Connor said.

"The atomic clock is what is commonly used in GPS satellites and in other quantum computing and astronomy applications but our clock is set to disrupt these current applications."

The lab-based version already has an existing customer in the Defence Science and Technology Group (DST Group) in Adelaide, but Associate Professor O'Connor said the research group was also looking for more clients and was in discussion with a number of different industry groups.

The research group is taking part in the Commonwealth Scientific and Industrial Research Organisation's (CSIRO's) On Prime pre-accelerator program, which helps teams identify customer segments and build business plans.

Customisable Ethernet switch designed for embedded applications

The introduction of the LDD-ES8, a customisable gigabit Ethernet switch module for industrial, commercial and building automation data services, has been announced by LDD Technology. The standard LDD-ES8 module is an 8 port unmanaged Ethernet Switch on a PC/104-Plus form factor intended for use in embedded applications. It features a high performance, low latency, switch able to handle full-rate gigabit packets on all ports simultaneously.

Auto-negotiation allows each port to operate at 10/100/1000 Mbits with dual LEDs per port to indicate negotiated speed and link activity. Power is provided from the PC/104 stack or through a Molex Microclasp connector. The LDD-ES8 module is designed for fully independent operation but a USB port is provided to allow monitoring of port performance if required. Power consumption is typically 5W with all ports operating at 1 Gbit/sec.The LDD-ES8 Gigabit Ethernet switch was developed in response to a number of enquiries for custom designed products from customers who had been unable to find suitable off-the-shelf products which met their performance, footprint and end product life requirements.LDD Technology is able to offer an efficient and cost-effective customisation service in the event that customers require a design with a different number of ports or in a different form factor. The module has been designed using programmable FPGA technology which offers end users a further range of customisation options not normally found on competitive products based on dedicated devices with limited programmability.This allows customers the option of including the functionality of the standard Ethernet Switch into other designs which may require Ethernet switching as part of a more complex system with additional interfaces or processing being included in the FPGA as required.“Our LDD-ES8 Gigabit Ethernet Switch is an excellent example of how our extensive custom design experience for many different clients can be used to create a flexible standard solution for many applications” commented Malcolm Locke, Managing Director of LDD Technology.

TI introduces the industry's smallest gate driver and power MOSFET solution for motor control

Texas Instruments (TI) (NASDAQ:TXN) today introduced two new device families that help reduce size and weight in motor drive applications. When used together, DRV832x brushless DC (BLDC) gate drivers and CSD88584/99 NexFET™ Power Blocks require as little as 511 mm2, half the board space of competing solutions.

The DRV832x BLDC gate drivers feature a smart gate-drive architecture that eliminates up to 24 components traditionally used to set the gate drive current while enabling designers to easily adjust field-effect transistor (FET) switching to optimize power loss and electromagnetic compliance. The CSD88584Q5DC and CSD88599Q5DC power blocks leverage two FETs in a unique stacked-die configuration, which doubles power density and minimizes the FET resistance and parasitic inductances typically found in side-by-side FET configurations.An 18-volt compact BLDC motor reference design demonstrates how the DRV8323 gate driver and CSD88584Q5DC power block can drive 11 W/cm3 power and enable engineers to jump-start their designs for smaller, lighter-weight power tools, integrated motor modules, drones and more.

Benefits of using a CSD88584/99 and DRV832x device together
Maximum power density: The combined solution delivers 700 W of motor power without a heat sink, providing 50 percent higher current than conventional solutions without increasing the footprint.
High peak current: As demonstrated by the 18-volt BLDC reference design, the smart gate driver and power block are capable of driving a peak current of up to 160 A for more than 1 second.
Optimal system protection: The combination enables shorter trace lengths and actively prevents unintended FET turn-on, while also providing undervoltage, overcurrent and thermal protection.
Superior thermal performance: The CSD88584Q5DC and CSD88599Q5DC power blocks come in TI's DualCool™ thermally enhanced package, which enables designers to apply a heat sink to the top of the device to decrease thermal impedance and increase the amount of power dissipated to maintain safe operating temperatures for the board and end application.
Clean switching: The power blocks' switch-node clip helps eliminate parasitic inductance between high- and low-side FETs. Additionally, the DRV832x gate driver's passive component integration minimizes board traces.

Tools and support to jump-start design
In addition to the 18-volt BLDC motor reference design, engineers can search for other motor reference designs that use the power blocks and gate drivers to help solve their system design challenges. The three-phase smart gate-driver evaluation module (EVM) allows designers to drive a 15-A, three-phase BLDC motor using the DRV8323R gate driver, CSD88599Q5DC power block and MSP430F5529microcontroller LaunchPad™ development kit. The EVM is available from the TI store for US$99.00.

Package, availability and pricing
The new DRV832x BLDC smart gate drivers offer peripheral and interface options for engineers to select the best device for their design: with or without an integrated buck regulator or three integrated current-shunt amplifiers. Each device option is available in a hardware or serial interface and comes in quad flat no-lead (QFN) packaging. The CSD88584/99 power blocks come in DualCool small outline no-lead (SON) packaging, with 40- or 60-V breakdown voltage (BVDSS) choices.

A layer of diamond can prevent high-power electronic devices from overheating

Powerful electronic components can get very hot. When many components are combined into a single semiconductor chip, heating can become a real problem. An overheating electronic component wastes energy and is at risk of behaving unpredictably or failing altogether. Consequently, thermal management is a vital design consideration.This becomes particularly important in devices made from gallium nitride. "Gallium nitride is capable of handling high voltages, and can enable higher power capability and very large bandwidth," says Yong Han from the A*STAR Institute of Microelectronics. "But in a gallium nitride transistor chip, the heat concentrates on tiny areas, forming several hotspots." This exacerbates the heating problem.

Han and co-workers demonstrate both experimentally and numerically that a layer of diamond can spread heat and improve the thermal performance of gallium nitride devices.The researchers created a thermal test chip that contained eight tiny hotspots, each 0.45 by 0.3 millimeters in size, to generate the heat created in actual devices. They bonded this chip to a layer of high quality diamond fabricated using a technique called chemical vapor deposition. The diamond heat spreader and test chip were connected using a thermal compression bonding process. This was then connected to a microcooler, a device consisting of a series of micrometer-wide channels and a micro-jet impingement array. Water impinges on the heat source wall, and then passes through the micro-channels to remove the heat and keep the structure cool.Han and the team tried their device by generating 10–120 Watts of heating power in test chips of 100 and 200-micrometer thickness. To dissipate the heating power, the diamond heat spreading layer and microcooler helped maintain the structure at a temperature below 160 degrees Celsius. In fact, the maximum chip temperature was 27.3 per cent lower than another device using copper as the heat spreading layer, and over 40 per cent lower than in a device with no spreading layer.The experimental results were further confirmed by thermal simulations. The simulations also indicated that the performance could be improved further by increasing the thickness of the diamond layer, and that good bonding quality between the gallium nitride chip and the diamond heat spreader was crucial to obtain the best performance."We next hope to develop a novel micro-fluid cooler of higher and more uniform cooling capability, and to achieve thermal management using a diamond layer of high thermal conductivity near an electronic gate," says Han.

Wireless microcontroller integrates MCU and Bluetooth smart radio

The CC2640R2F SimpleLink ultra-low-power wireless microcontroller from Texas Instruments (TI) is in stock at Mouser Electronics. Part of TI’s CC26xx SimpleLink family of 2.4GHz devices, the CC2640R2F microcontroller features a small, single-chip system that integrates a flash-based microcontroller and Bluetooth Smart radio to target Bluetooth 4.2 and Bluetooth 5 low-energy applications.

The microcontroller combines a 61μA/MHz ARM Cortex-M3 microcontroller and a rich peripheral set that includes an 8.2μA/MHz sensor controller. The 48MHz ARM microcontroller offers 128 kBytes of flash and 28 kBytes of SRAM and supports over-the-air (OTA) updates.
The sensor controller is ideal for interfacing external sensors and for collecting analog and digital data autonomously while the rest of the system is in sleep mode.
The device includes a 12-bit analogue-to-digital converter, up to 31 general-purpose inputs and outputs (GPIOs), and built-in robust security on chip with one of the simplest radio frequency (RF) and antenna designs available.
Minimal RF expertise is required to implement the device, which helps make development and layout extremely easy.
The wireless microcontroller is available in 2.7×2.7 mm WCSP and 4×4, 5×5 and 7×7 mm QFN packages, and is designed for a board array of wireless Internet of Things (IoT) applications, including health and fitness, industrial, and home and building automation.
With ready-to-use protocol stacks (including the SIMPLELINK-CC2640R2-SDK software development kit for Bluetooth 5), the SimpleLink portfolio of wireless connectivity solutions not only offers designers maximum flexibility and support but also delivers multi-standard capabilities with code- and pin-compatibility across Bluetooth Smart, 6LoWPAN, ZigBee and ZigBee RF4CE.

Microchip 8bit MCUs get up to 128kbyte flash

Microchip’s PIC18F ‘K42’ microcontrollers are available with up to 128kbyte (from 16kbyte) of flash memory in packages from 28-48 pins. Max clock speed is 64Mbit/s and there is up to 1kbyte data EEPROM and 8kbyte of SRAM.

The firm has gone big on its ‘core independent peripherals’ (CIP) to allow functions to be implemented in hardware, saving code, validation time, core overhead, and power consumption, said Microchip.

Intended for automotive, industrial control, IoT, medical and white goods, they include peripherals for safety critical applications including cyclic redundancy check with memory scan, a windowed watchdog timer, a 24bit signal measurement timer and a hardware limit timer, as well as up to eight hardware PWMs, complementary waveform generation for power bridges, and multiple communications interfaces.

Analogue peripherals including a zero crossing detector, constant current I/O (see below), a comparator, and a 12bit ADC with computation – the latter for automating capacitive voltage division (for touch sensing), averaging, filtering, over-sampling, and threshold comparison.

Constant current I/O

The constant current I/O feature allows the sink and source current of a pin to be set to 1, 2, 5 or 10mA. This has to be used with caution because the pin circuitry cannot dissipate much static power, so an “external resistor must be inserted in series with the load to dissipate most of the power,” said Microchip.

It has an example, with a 5V rail and a load which needs 1mA and whose voltage drop can be between 1.0 and 1.5V. The external resistor and pin circuitry has to make up 3.5-4V difference, so the resistor  needs to be chosen to drop 3.5V at of 1 mA, said Microchip, then the pin can make up the 0-500mV variable difference.

A ‘memory access partition’ supports data protection and bootloading, and the ‘device information area’ is a dedicated memory space for factory programmed device ID and peripheral calibration values.

Building blocks

• ADC with computation
• zero crossing detector
• 10bit PMW
• complementary waveform generator
• numerically controlled oscillator
• data signal modulator
• hardware limit timer
• 24bit signal measurement timer
• configurable logic cell
• crc/scan module
• windowed watchdog timer
• peripheral pin select
• direct memory access
• temperature indicator
• data signal modulator
• 5bit DAC
• UART, SPI, and I2C

lm386 amp Audio Amplifier

Small Audio amp using LM 386 IC

This is simple and Small Audio power Amplifier project that you can make at home easily. We will make this project using a Small lm386 IC which is a 8 pin IC. You can make your own tiny simple amplifier using this lm386 IC. Due to its small size lm386 is perfect for various projects like radio amp, tiny Guitar amp amplifier.

It supports various range of supply voltage, 4V - 12V or 5V - 18V. The Audio amplification Gain can be adjusted. You can find the schematic and other additional components below. If you are planning on some hobbyist projects which includes sound systems, then amplification can be handled by this lm386 audio amp. There are many schematics available on internet based on lm386, so you can change the components based on your requirements in the schematic.

The gain is adjusted with a potentiometer. You will need an external power supply for this amplifier. Since the voltage supply can be in between 5V - 18V so you can use batteries.

This schematic was given to me by my professor, while working on an audio system in lab for some project long time ago. Hence I am sharing with you. Please don’t mind for my hand drawn model of this amplifier schematic.

Requirements for Amplifier

Components	Value	Quantity	Notes
Resistance	22K	1	-
Resistance	1R5	1	-
Capacitor	10uf	1	Between Pin 1 and 8
Capacitor	100n	1	-
Capacitor	330u	2	-
IC	LM386	1	Amplifier

lm386 schematic for Audio Amplifier

Schematic for lm386 small amp Audio

lm386 pin diagram

 

lm386 on breadboard

Power amplifiers are something which converts low voltage input to high voltage output; hence this audio amplifier amplifies the low voltage audio into high output. During my college days I wanted to make a small audio power amp that you can put in your pocket and tune up sound in headphone hence I used this IC. For more specifications on lm386 you can refer the data sheet. A short Google on lm386 must let you to various data sheets for the same. Please refer the lm386 data sheet before changing components.

The voltage gain can be adjusted by adding a potentiometer across pin 1 and 8. Choose the speakers according to your requirement. I suggest keep gain to as low as zero when you done with schematic and then gradually tune up the potentiometer to avoid the speakers to damage. (if speakers you choose are not powerful enough). A pretty powerful amp with a low voltage battery.

PS: Just in case if you are doubtful then, pin 7 is unused pin in the IC.

lm 386 Audio Amplifier project

Thanks for reading