Company Related Questions

1) How much is the design experience of RFIC solutions Team?
RFIC Solutions team has a collective experience of 40 years in the RF field. Highly motivated engineers, meet the challenges of the market, empower the company to achieve the desired goal. The team has collectively developed more than 600 RF ICs covering 0 GHz to 100 GHz Frequency band over last 20 years at previous companies. The team has catered the need of various companies such as INTEL, MICRO LINEAR, ATHEROS, BROADCOM and many others.


2) What is the experience of the team in designing consumer wireless products for high volume manufacturing?
The RFIC team has delivered more than 30 million RF ICs for Wireless LAN, Cordless & Cellular Phone, & other wireless applications. RFIC team has extensive RF industry knowledge with many years of background in deploying Broadband Wireless Systems. We have strong background in modules, integrating combination of Antennas, Passives and Active Si in one tiny low cost substrate. Dr. Moghe CEO RFIC Solutions has credited world's most complex synthesizer MMIC chip at 45 GHz, with 35 functions on a chip. We have developed Wireless CDPD PCMCIA and PCS modems for the Cellular and PCS networks and PCMCIA modem products for Mobitex network using MMIC technology.

To add up, the company offers design services at high competitive rates making it very potent to provide the consumer wireless products for high volume manufacturing.


3) List some of the major wireless applications that RFIC Solutions Inc. provides design services for?
Wireless applications is a vast and potential market, thus we focus upon some of the areas that are listed below. We also provide a range of other services in design and application according to the customer needs.
• WiFi
• WiMax
• 3G and Cellular System
• RFID Systems
• Ultra Wideband (UWB)


4) Which are the various IEEE standards for wireless communication that RFIC Solution Inc. is actively involved with?
Standards that are specified by IEEE namely are
• 802.11a/b/g WLAN
• 802.16a/d/e WiMax
• IEEE 802.20 MWBA
Dr.Moghe has an active participation in the workgroup on IEEE 802.16 WiMax. Active involvement in the workgroup gives the company a hawk eye view of current happenings in the wireless standards.

Introduction And Basics Of RF Circuits

1) Differentiate between Analog and Digital IC design.
Analog circuit design is different from Digital Circuit design in following aspects:
• Layout is critical since the routing should be done according to RF design rules
• Layout in digital can be completely automatic which is not the case in analog
circuits
• Grounding issue is critical in Analog or RFIC compared to Digital IC
• Size of analog IC’s are large compared to digital since it comprises of inductors capacitors and resistors where as digital IC’s includes only capacitors and resistors.

2) Which are the various processes used for fabrication of IC’s?
The different processes used for fabrication of IC’s are:
• GaAs
• SiGe
• CMOS
• BiCMOS Know more >>

3) What is the basic purpose of using EM simulation?
Basic purpose of EM simulation is to predict the actual behavior of RF Circuits considering all the parasitic and coupling. This is not considered in circuit simulation.

4) List the instruments required for testing RF Modules and IC’s Instruments required for RF testing are:
• Spectrum Analyzer
• Vector Network Analyzer
• Noise Figure Meter
• Power Meter

5) Which are basic blocks that comprise the RF Transceiver?
RF Receiver consists of
• Low Noise Amplifier/RF Amplifier
• Mixer
• Local Oscillator
• Demodulator
• Automatic Gain controller
• Automatic Frequency controller.
• Filters
• Switch

RF Transmitter consists of
• RF power amplifier
• Modulator
• Carrier Oscillator
• PLL
• Filters
• Switch

6) What is the basic function of a power amplifier?
The main function of RF power amplifier is to boost the power level of a Signal so that it can travel a significant distance. Power amplifiers are required in all the transmitters

7) What is the basic function of a low noise amplifier?
The main function of Low Noise Amplifier is to amplify the weakest possible Signal with Noise Figure as low as possible during reception and to improve the sensitivity and dynamic range of a receiver.

8) What is the basic function of a Mixer?
Frequency translation is the key role of Mixer. Output contains the sum or difference of two frequencies i.e. RF frequency and LO(Local Oscillator)

9) How is the cost of fabrication related to IC die size? How the die size affects yield factor?
Let us take an example:
Size of a wafer=6 inch
Size of a single die=1mm X 1mm
Cost of a 6 inch wafer=$2000
Then the total no of die could be approx
No. of die=total area of wafer/area of a single die
=(3 X 3 X 2.54 X 2.54)/(0.1 X 0.1)
=18232
Therefore cost of single die=$2000/18232
=$0.109

A wafer of ICs will cost the same to fabricate whether it contains 10 000 circuits or 100 circuits. Clearly the larger the area the circuit occupies, the more expensive the die. This is compounded by the fact that larger die will also exhibit lower yields. Figure is a graph showing the number of die available from a single wafer versus die size. Wafer diameters of 3", 4" and 6" are considered. The figures take account of the area lost to circuits at the edge of the wafer and make an allowance for area devoted to Process Control Monitor (PCM) cells. Functional yield is not considered since this is a complex function of process defect density, device variation, circuit design and performance specification. However it is certain that yield will degrade with increasing die size

10) What are the challenges in MMIC design?
Challenges in MMIC design
• Choosing the right device in case of active circuits
• Minimizing cross coupling and parasitic effects in layout
• Reducing the die size which is directly proportional to the cost
• Designing keeping in mind the yield
• Designing taking into account the packaging of die (After packaging
there is some change in performance)
• Choosing right package
• Performance of the circuit should have minimal variation over
temperature and bias voltage

11) Which are the different semiconductor technologies for MMIC designs?
The different semiconductor technologies:
• Bipolar
• MESFET
• PHEMT Know more >>