Our customer is a leading global organization providing components and technology solutions to electronics manufacturing companies around the world. We were handed the responsibility of a current sensor IC that monitors charge/discharge current of a rechargeable battery, e.g. in a mobile phone, while remaining insensitive to the variations of the supply voltage. We took charge of the entire design trajectory along with evaluation that was needed to make the final product better than competition.
The aim was to measure high-side current irrespective of the supply voltage that ranged from 1.8 V to 4.5 V. Sense current range was 1 mA to 1000 mA, using an external sense resistor of 10 mΩ. The basic principle for this current sensor is based on the conversion of the current through a (small) external resistor into a voltage. We developed an advanced differential voltage measurement circuit which is insensitive to the common-mode (=supply) level. The differential voltage to be measured is very small (microVolt to milliVolt range). Exact design specifications were defined during the design phase in collaboration with the customer, which allowed functionalities to be implemented optimally for the final product. Despite uncertainties in specifications and IC process models fully functional first silicon was quickly realized, and then the entire product development was covered in very short time.
First-silicon design and layout in 3 months from start to tape-out.
WE ARE PROUD
A versatile and robust differential voltage sensor architecture was developed, including analog amplification, analog-to-digital conversion (ΣΔ) and a digital bus-interface. To beat the challenge to measure differential voltages in the range of microVolts while the offset voltage of an uncompensated amplifier in this technology was 10 mV, we successfully developed a highly-efficient offset compensation mechanism.
The clever design incooperated an easy way to interact between multiple voltage domains; a high-side voltage domain containing the amplifier and ADC and a low-side domain containing the interface.
The IC was developed in a customer-specific low-cost CMOS process technology (0.6 µm). We started with setting up a custom PDK with very limited process information. Our experience of working with CMOS technologies on various nodes and ‘SystematIC’ design methodologies helped us to create robust circuits and achieve the satisfactory performance parameters. Besides good measurement accuracy also a very low power consumption was achieved, in operation (uA range) as well as in standby (nA range).
BENEFITS FOR CUSTOMER
- Customer received a versatile and robust (high-side) differential voltage readout circuit
- Suitable for various generations of sensor products including current sense over a sense resistor
- Low-power circuit designs
- Circuit design and layout in customer-owned process
- Supported IC evaluation and final IC product definition
- The quick realization of a functional first-silicon prototype opened up test opportunities and refinement of the final product definition and specifications which implied a significant gain in time-to-market.
KEY TECHNICAL STATISTICS
- Process: 0.6 µm CMOS
- High-resolution differential voltage sensing (10 uV)
- Common-mode (Supply) input range 1.8 V to 4.5 V
- Current consumption: 3 µA (at 10 measurements per second)
- Non-linearity: <1 %
- Standby current: in nA range
OUR OTHER SUCCESS STORIES
IC solutions that are tailor made for you can help you achieve your business goals.
SystematIC was founded to help businesses envision, plan, and develop such custom IC solutions.
INTEGRATED MAGNETIC SENSOR
Our customers is the Isolation Products Division of a semiconductor leader, who has a strong portfolio based on optical isolation techniques. Application of this fully integrated single chip magnetic sensor opened a new line of magnetic isolation products. Based on our reference high speed magnetic design in 2 months’ time a 180nm CMOS prototype was shipped.
PROXIMITY AND AMBIENT LIGHT DETECTION
SystematIC has designed a family of products which combines Ambient Light Sensor (ALS) and Infra-red Proximity Detection Sensor (PS) in a single SoC. The ambient light sensor matches the response of the human eye. The infra red proximity sensor measures the distance to an object. Our client is a leading global organization providing components to mobile phone manufacturing companies.
We were handed the responsibility of a current sensor IC that monitors charge and discharge currents of a battery in a mobile phone and will remain insensitive to the variations of the supply voltage. We took charge of the entire design trajectory along with evaluation and redesign that was needed to make the final product a notch better than competition.
TIRE PRESSURE MONITOR
In this project we developed an analog front-end architecture for a given capacitive MEMS pressure sensor. The front end must accurately measure the pressure in a tire and be robust against leakage, parasitics and noise. The SystematIC methodology was applied. First off, the sensor was electronically modelled to determine an optimal excitation and read out architecture. Next, during the detailed design phase the front-end was designed and layouted for a modern automotive IC application, including safety and test features.
X-RAY DETECTOR READOUT
The customer has a leading international position in industrial X-ray crystallography systems. In one of these products a multi-channel HV passive X-ray sensor is applied for material analysis and an accurate matched channel readout and signal processing ASIC is required. SystematIC proposed an architecture of ultra-low noise front ends that are noise optimized to the sensor element and applied in a matched channel configuration. The digital electronics where designed as special CMOS CML logic to obtain low crosstalk.
AC LED DRIVER IC
Our customer produces a range of AC LED modules for lamp manufacturers. The products were originally built with discrete components, a different set for each module type. For performance enhancement and simplification of production steps and supply chain, the customer was looking for a custom ASIC solution. The customer was also expecting improved performance on TRIAC dimmer compatibility and a reduction in product costs. With a programmable high-voltage ASIC and only a few external components (rectifier, fuse and surge) all module types can be made. LED modules with such an ASIC are directly driven from the AC mains voltage, are low-cost and are very compact and reliable. An electronic solution was created that made the customer AC LED lamp compatible with TRIAC dimmers. A discrete prototype was built and demonstrated to the customer just a few weeks after the first contact. The discrete electronics where chosen such that they could be implemented in a HV IC process.
POINT-OF-LOAD POWER CONTROLLER
Our customer, a fabless semiconductor company, started a new product line of drivers and controllers for power converter applications in industrial applications. SystematIC took care of the design of a complex power controller IC targeting application in Point-of-Load Power Modules, used in Ethernet Routers and Switches and other Industrial Applications. The customer’s approach was to offer a very versatile IC to the market that also realized excellent performance parameters (efficiency, ripple, etc). The customer discovered a strong market interest and had marketing & sales and application support in place but lacked the IC design resources for a quick product development. Within a year SystematIC developed all accurate analog functions in a new IC process and delivered the verified mixed-signal chip design and layout.
INTEGRATED POWER SWITCH
Applications supporting plug-and-play connections require (accurate) over-current protections, preferably implemented in a low-cost solid-state IC. For a division of a large semiconductor company the accurate current control was a design challenge that was tackled by involving SystematIC in the design. The area, cost-of-silicon and on-resistance of the integrated power switch are relevant parameters for the technology choice, but in any case dictate preference for an NMOS power switch. Using an NMOS switch however complicates the design of driver and sensing circuits. SystematIC did the challenging full-chip circuit design, including current sensing circuits using low-offset chopped amplifiers, adjustable over-current current control, over-temperature protection, and push-pull chargepumps to drive the NMOS.
EAR PROTECTION CONTROL IC
Our customer DEC develops and produces Dynamic Sound technology products which can typically be used as stand-alone hearing protection or embedded in headphone systems, hearing aids and hearables. The IC we designed for DEC was an example of an integration project for SME and it covers most aspects of a SystematIC turnkey solution. Our contribution extends from system study to implementation, manufacturability and testability for ears, from zeroing in the IC process to IC design and layout and the production preparation.
State-of-the-art electric propulsion (EP) systems used in satellites may exhibit impressive performance, but the used technologies cannot be scaled down in size and power whilst retaining system performance. As a result, no conventional technologies for propulsion are available for the upcoming micro- and nanosatellite market. SystematIC partners in the HiperLoc-EP project which aims to use a novel electric propulsion approach and develop an Electrospray Colloid Electric Propulsion System (ECEPS) suitable for small (cubesat) form factors.