Mixed-Signal & Analog PCB Design Services | Low-Noise Hardware Experts

Design of Analog Circuits and Schematics

The circuits we produce are used for sensor conditioning, amplification, filtering, conversion and protection. The configurations of the circuits vary according to the requirements of the specific project, and may involve using operational amplifiers, instrumentation amplifiers, ADCs, DACs and audio codecs, comparators, current sensors and precision voltage devices.

For each circuit we assess its elements against functional requirements including input range, bandwidth, noise density, offset, drift, common-mode range, power consumption and availability.

Design of Analog Front-End

Analog front-end plays a key role in terms of the quality of information which is passed on to the processor. Our engineers are working on the design of the front ends for temperature, pressure, current and voltage, vibration, audio, gas, optical and biopotential sensors.

The work may include such processes as matching impedance, anti-alias filtering, gain adjustment, protection and biasing of input, and using differential signals. We always analyze the whole signal path so that amplifier noise, ADC accuracy and reference value correlate to the data instead of being considered separately.

ADC and DAC Integration

High-resolution data converters require careful power, reference, grounding and layout decisions. We help select and integrate suitable SAR, delta-sigma and audio converters based on sample rate, resolution, latency and power requirements.

Converter selection is only the beginning. Reference bypassing, driver settling, input filtering, clock quality and return-current control can directly affect effective performance. We place supporting components close to the relevant pins and keep sensitive converter inputs away from clocks, switching nodes and wireless sections.

Low-Noise PCB Layout

Our mixed-signal layout process begins with functional partitioning. Sensitive analog components are grouped around the signal source, while processors, memory, displays and communication devices are positioned according to their digital and high-speed requirements.

We maintain short analog paths, uninterrupted return paths and controlled placement of domain boundaries. Clocks and fast digital traces are prevented from crossing sensitive analog regions. Power regulators are positioned so their switching-current loops remain compact and separated from measurement circuitry.

Grounding is derived from the converter system, its design and the paths of currents. We do not follow a single rule of split grounding. In some systems, the use of ground pads has been ineffective while applying a continuous ground plane with proper placement and routing is a better solution than a simple split ground.

Analog Devices and Texas Instruments stress the importance of placement, routing and control of return current paths in mixed-signal board designs.

Power-Supply and Reference Design

In order to create a low noise signal chain, it is crucial to have clean and stable power supply. We design our regulator stages by using appropriate LDOs, DC-DC converters, ferrite beads, bulk capacitors and local decoupling. In cases where switching conversion is required, we evaluate switching frequency, harmonic content, load transients and distance to sensitive electronics.

Separate supply filtering may be used for ADCs, references, amplifiers and radio sections. Component placement and current-loop area are treated as part of the power design—not as tasks left until routing.

Simulation, Prototyping and Testing

We apply signal and circuit analysis depending on the task at hand in order to perform evaluations such as gain, bandwidth, stability, filtering, and component tolerances before actual manufacturing.

When the board has been assembled, it can be tested using techniques such as rail sequencing, measurement of power consumption, analysis of the signal chain, measurement of the noise floor, communication testing, and thermal testing.

We can also provide design files, Gerbers, drill data, assembly drawings, pick-and-place files, bill of materials and engineering notes for prototype or production transfer.