RF RF CircuitsCircuits DesignDesignGrzegorz Grzegorz BudzyBudzyńń

High High integrationintegration scale packagesscale packages

References[1] Medi A.,”MMIC Design and Technology”

[2] ECE145B/ECE218B Mixer Lectures

[3] www.analog.com

[4] LTC 6420-20 documentation; www.linear.com

[5] MAX2657 documentation; www.maxim-ic.com

[6] ADL5571 documentation; www.analog.com

[7] MAX2043 documentation; www.maxim-ic.com

References

[8] ADL5385 documentation; www.analog.com

[9] LTC5535 documentation; www.linear.com

[10] ADF5002 documentation; www.analog.com

[11] AFBR-57M5 documentation; www.avagotech.com

[12] ADF7242 documentation; www.analog.com

Plan

• High frequency analog integrated circuits

• Integrated circuits for high speed serial

communication:

– In electrical domain

– In optical domain

High frequency analog integrated

circuits

High performance solutions

Source: [3]

Introduction

• The high-frequency (RF) can be divided intoseveral categories:–Amplifiers

–Up- and downconverting mixers

–Modulators/ demodulators

–VCOs

–Detectors

–Prescalers

– Transmitters/ Receivers

Ampifiers

• Gain blocks:–General-purpose broadband amplifiers that

operate from low frequencies up to 6 GHz

–Devices are usually 50 Ω internally matched with integrated internal bias circuitry, therefore minimizing the need for external components

Gain block – LTC6420-20

• Dual high-speed differential amplifiertargeted at processing signals from DC to 300MHz

• Easy to use, with minimal support circuitry required

• The output common mode voltage is set using an external pin, independent of the inputs

• The gain is internally fixed at 20dB (10V/V)

Gain block – LTC6420-20

Source: [4]

Gain block – LTC6420-20

Source: [4]

Gain block – LTC6420-20

Source: [4]

Ampifiers

• Low noise amplifiers (LNA):–Because it is the first amplifier in the receive

path, the parameters of LNA are critical for overall system performance

– It must be able to successfully amplify very low level signals without adding a significant amount of noise

–Good quality LNAs operate up to several GHz

LNA – MAX2657

• MAX2657 is a high-gain, low noise LNA for GPS, Galileo and GLONASS applications

• RF frquency range: 1563-1620 MHz

• Ultra-low noise figure: 0.8 dB

• Gain: 19 dB

• Supply: 1.6-3.3 V/ 4.1 mA

• Only three external elements necessary

LNA – MAX2657

LNA – MAX2657

Source: [5]

LNA – MAX2657 - noises

Ampifiers

• Power/driver amplifiers:–Driver amplifier are used to drive the power

amplifier stages

–Driver amplifier should have very high linearity for a given output power to enable low distortion and high output drive

–An RF power amplifier converts a low-power radio frequency signal into a larger signal of significant power, typically for driving the antenna of a transmitter

Power amplifier – ADL5571• The ADL5571 is a high linearity 2.5 GHz to 2.7 GHz

power amplifier designed for WiMAX mobile terminals and CPEs using TDD operation at a duty cycle of 50% or lower

• Gain: 29dB

• Output power level up to 27 dBm

• Input matched to 50 Ohm

• Multiple operating modes to reduce battery drain:

– Standby mode: 9 mA

– Sleep mode: <1 μA

Power amplifier – ADL5571

Power amplifier – ADL5571

Source: [6]

Power amplifier – ADL5571

Source: [6]

Mixers

• Mixers have a wide variety of applications in communication systems:– Receivers

• up or down conversion

• demodulation of SC SSB or SC DSB

• input must support large dynamic range

• AGC

– Transmitters• up conversion

• modulation: amplitude and phase

• input has optimum signal level for high performance

Mixers – important parameters

• Image rejection

• Conversion gain: voltage or power

• Port-to-port isolation: dBc

• Large signal performance:– gain compression: P1dB

– intermodulation distortion spec: third-orderintercept (TOI)

• Small signal performance: noise figure

• Operating range: Spurious-free dynamic range

Mixers – MAX2043

• High-linearity passive upconverter or

downconverter mixer

• Designed for UMTS/WCDMA, DCS, PCS, and

WiMAX base-station applications

• The onchip baluns allow for a single-ended RF

input for downconversion

• Single-ended LO inputs

Mixers – MAX2043

Source: [7]

Mixers – MAX2043

• 1700MHz to 3000MHz RF Frequency Range

• 1900MHz to 3000MHz LO Frequency Range

• DC to 350MHz IF Frequency Range

• 7.5dB Typical Conversion Loss

• 7.8dB Typical Noise Figure

• -160dBc/Hz LO Noise

• -52dBm LO Leakage at RF Port

• -3dBm to +6dBm LO Drive

• +5V Single-Supply Operation

Modulators/Demodulators

• I/Q modulators/ demodulators are used inadvanced modulation circuits (like QPSK orQAM)

• Broadband operation – couple of GHz

• Ideal for a wide range of wireless infrastructureapplications, including 2G, 2.5G, 3G and 4G cellular base station radios, high-capacity point-to-point and point-to- multipoint radio links, wireless LAN and wireless local loop equipment

Modualtor – ADL5385

• Silicon, monolithic, quadrature modulator

designed for use from 50 MHz to 2200 MH

• Excellent phase accuracy and amplitude balance

enable both high performance intermediate

frequency (IF) and direct radio frequency (RF)

modulation for communication systems

• Takes the signals from two differential baseband

inputs and modulates them onto two carriers in

quadrature with each other

Modualtor – ADL5385

Source: [8]

Modualtor – ADL5385

Source: [8]

VCO/ PLL

• The Phase Locked Loop (PLL) method offrequency synthesis is now the most commonlyused method of producing high-frequencyoscillations in modern communicationequipment

• PLL circuits are also used to demodulate FM, AM or FSK signals

• The most critical part of PLL loop are VCO andphase detectors

VCO – MAX2620

• Combination of low-noise oscillator with two output buffers in a low-cost, plastic surface-mount, ultra-small µMAX® package

• Integrates functions typically achieved with discrete components

• Oscillator works in 10-1050 MHz bandwidth

• Low-Phase-Noise Oscillator: -110dBc/Hz

• Two Output Buffers Provide Load Isolation

VCO – MAX2620

Source: [8]

VCO – MAX2620

Detectors

• RF detectors are used for different things andcan be divided into categories:– RF Schottky Peak Detectors:

• For monitoring and control of RF power in receiving andtransmitting path

• The RF input voltage is peak detected using an on-chip Schottky diode

• The detected voltage is usually buffered

– RF Log Detectors• RF log power detectors provide a DC output voltage that is

log-linearly proportional to its input power level

Detectors• RF detectors are used for different things and

can be divided into categories:– RF Log Detectors

• RF log power detectors provide a DC output voltage that is log-linearly proportional to its input power level

• RF log detectors accept usually large dynamics of the inputsignal (60-70 dB)

– RF RMS Detectors• RMS power detectors outputs a DC voltage that is linearly

proportional to the log input power

• RMS measurement capability provides accurate RF power readings to within ±0.2dB regardless of waveforms that have high crest-factor modulated content, multi-carrier or multitone

Peak detector – LTC5535• Temperature Compensated Internal Schottky

Diode RF Detector

• Input Frequency Range: 600MHz to 7GHz

• Wide Input Power Range: –32dBm to 10dBm

• External Gain Control

• Precision VOUT Offset Control

• Low Starting Voltage: 200mV for Gain = 2

• Wide VCC Range of 2.7V to 5.5V

• Low Operating Current: 2mA

• Available in a Low Profile (1mm) SOT-23 Package

Peak detector – LTC5535

Source: [9]

Peak detector – LTC5535

Source: [9]

Prescalers

• RF prescalers are used for reducing the inputfrequency by a certain factor

• The prescaling factor is usually a power of 2 (2, 4, 8 or 16)

• The prescaling factor is constant or can be changed by changing voltages at configrationpins

• Some applications:– PLL frequency range extender

– Point-to-point radios

– VSAT radios

Prescaler – ADF5002

• Divide-by-8 prescaler

• High frequency operation: 4 GHz to 18 GHz

• Integrated RF decoupling capacitors

• Low power consumption

• Active mode: 30 mA

• Power-down mode: 7 mA

• Low phase noise: −153 dBc/Hz

• Single dc supply: 3.3 V

• Small package: 3 mm × 3 mm LFCSP

Prescaler – ADF5002

Source: [10]

Prescaler – ADF5002

Source: [10]

Optical transceiver AFBR-57M5• Optical transceiver supporting high-speed serial

links over multimode optical fiber at signaling rates up to 2.125 Gb/s

• 850 nm Vertical Cavity Surface Emitting Laser (VCSEL) source technology

• Link lengths at 2.125 GBd:– 300 m with 50 μm MMF, 150 m with 62.5 μm MMF

• Link lengths at 1.0625 GBd:– 500 m with 50 μm MMF, 300 m with 62.5 μm MMF

• Link lengths at 1.25 GBd:– 2 to 550 m with 50 μm MMF, 2 to 275 m with 62.5

μm MMF

Optical transceiver AFBR-57M5

Source: [11]

Optical transceiver AFBR-57M5

Source: [11]

Optical transceiver AFBR-57M5

Source: [11]

Electrical transceiver ADF7242

• Low Power IEEE 802.15.4/Proprietary GFSK/FSK Zero-IF 2.4 GHz Transceiver IC

• Frequency range (global ISM band)– 2400 MHz to 2483.5 MHz

• Programmable data rates and modulation– IEEE 802.15.4-2006-compatible (250 kbps)

– GFSK/FSK/GMSK/MSK modulation

– 50 kbps to 2000 kbps data rates

• Programmable output power– −20 dBm to +4.8 dBm in 2 dB steps

Electrical transceiver ADF7242

• Low power consumption– 19 mA (typical) in receive mode

– 21.5 mA (typical) in transmit mode (PO = 3 dBm)

– 1.7 μA, 32 kHz crystal oscillator wake-up mode

• High sensitivity (0.1% BER)– -96 dBm at 62.5 kbps (GFSK)

– −93 dBm at 500 kbps (GFSK)

– −90 dBm at 1 Mbps (GFSK)

– −87.5 dBm at 2 Mbps (GFSK)

Electrical transceiver ADF7242

Source: [12]

Source: [12]

Electrical transceiver ADF7242

Electrical transceiver ADF7242

Source: [12]

Source: [12]

Thank you for your attention