Nujira MIPI Presentation

Coolteq.L Single-Chip Envelope Tracking Supply Modulator Jeremy Hendy Nujira 1 Copyright © 2012 MIPI Alliance. All rights reserved. Legal Disclaimer The material contained herein is not a license, either expressly or impliedly, to any IPR owned or controlled by any of the authors or developers of this material or MIPI. The material contained herein is provided on an “AS IS” basis and to the maximum extent permitted by applicable law, this material is provided AS IS AND WITH ALL FAULTS, and the authors and developers of this material and MIPI hereby disclaim all other warranties and conditions, either express, implied or statutory, including, but not limited to, any (if any) implied warranties, duties or conditions of merchantability, of fitness for a particular purpose, of accuracy or completeness of responses, of results, of workmanlike effort, of lack of viruses, and of lack of negligence. ALSO, THERE IS NO WARRANTY OR CONDITION OF TITLE, QUIET ENJOYMENT, QUIET POSSESSION, CORRESPONDENCE TO DESCRIPTION OR NON-INFRINGEMENT WITH REGARD TO THIS MATERIAL. All materials contained herein are protected by copyright laws, and may not be reproduced, republished, distributed, transmitted, displayed, broadcast or otherwise exploited in any manner without the express prior written permission of MIPI Alliance. MIPI, MIPI Alliance and the dotted rainbow arch and all related trademarks, tradenames, and other intellectual property are the exclusive property of MIPI Alliance and cannot be used without its express prior written permission. IN NO EVENT WILL ANY AUTHOR OR DEVELOPER OF THIS MATERIAL OR MIPI BE LIABLE TO ANY OTHER PARTY FOR THE COST OF PROCURING SUBSTITUTE GOODS OR SERVICES, LOST PROFITS, LOSS OF USE, LOSS OF DATA, OR ANY INCIDENTAL, CONSEQUENTIAL, DIRECT, INDIRECT, OR SPECIAL DAMAGES WHETHER UNDER CONTRACT, TORT, WARRANTY, OR OTHERWISE, ARISING IN ANY WAY OUT OF THIS OR ANY OTHER AGREEMENT RELATING TO THIS MATERIAL, WHETHER OR NOT SUCH PARTY HAD ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. 2 Copyright © 2012 MIPI Alliance. All rights reserved. Nujira Company overview • Fabless IC vendor • World leader in Envelope Tracking • The only technology for broadband. All rights reserved. UK • Founder member of OpenET Alliance • Active participant in new MIPI ACI WG • Analog Control Interface – Envelope Tracking subgroup • Standardising physical interface between chips 3 Copyright © 2012 MIPI Alliance. . high efficiency PAs • >250 man-years investment in High Accuracy Tracking™ • Coolteq™ products cover power levels from <1W to 10kW+ • 133 patents granted & pending • Most extensive ET patent portfolio in the industry • Headquartered in Cambridge. UK • Design Centres in Edinburgh and Bath. All rights reserved. .Envelope Tracking – an overview Conventional PA Baseband / RF up converter DC/DC Converter Fixed Supply Voltage Dissipated as Heat Power Amplifier Planned standard from MIPI ACI Working Group Transmitted ET Power Supply Envelope signal Supply Voltage Dissipated as Heat Baseband / RF Up converter Power Amplifier Envelope Tracking PA Transmitted 4 Copyright © 2012 MIPI Alliance. LTE dissipation ~1. . but poor efficiency • Efficiency is strong function of waveform PAPR • LTE dissipation ~2x W-CDMA 3GPP power control slot time 0. All rights reserved.5 ms / 1 ms Average Power Tracking (APT) DC:DC • Per-slot tracking based on TX power control level • Improves efficiency at low power • Doesn’t help at high power • Same waveform dependence Envelope Tracking • Dynamic. high bandwidth supply tracking of signal amplitude • Improves efficiency in top 90% of TX power control range • Waveform-independent.2x W-CDMA 5 Copyright © 2012 MIPI Alliance.Envelope Tracking vs Average Power Tracking Direct battery connection • Simple. All rights reserved. .RF PA becoming the dominant consumer of power in handsets • LTE data = 10x 3G voice • Less than 1 day between recharges • More than 3W • Gets hot! • Challenging thermal design • High peak currents 4000 mW 3500 mW 3000 mW 2500 mW 2000 mW 1500 mW 1000 mW 500 mW 0 mW RF PA Transceiver Modem WiFi/BT/GPS Audio Apps Processor Screen & backlight W-CDMA voice 0 dBm HSUPA 15 dBm LTE 23 dBm 6 Copyright © 2012 MIPI Alliance. .LTE PA spending significant time at maximum power Data source: Signals Research Group.com) • Short bursts of TX data at max power • Highest spectral efficiency • PA spends >50% of its time at maximum power 7 Copyright © 2012 MIPI Alliance. 11. No. Oct 7.signalsresearch. 2010 (www. Signals Ahead report Volume 6. All rights reserved. 60x increase in RF PA energy consumption from 3G to LTE 10 Waveform Peak-to-Average Power Ratio.1 1 10 100 Average Handset transmit power control level. mW 3G voice 26 mW HSUPA data 250 mW Multiband LTE 1800 mW LTE data 1600 mW 1000 8 Copyright © 2012 MIPI Alliance. dB 9 8 7 6 5 4 3 2 1 0 0. . All rights reserved. L Envelope Tracking 40% saving 45% saving 55% saving DC:DC converter Coolteq ET modulator PA dissipation (DC:DC) PA dissipation (Coolteq) RF front end losses Transmitted RF (200 mW) 3G (W-CDMA) 3.Envelope Tracking power savings 2500 mW 2000 mW 1500 mW 1000 mW 500 mW 0 mW Measurements of commercial PA device at 23 dBm transmitted RF power. .5G (HSUPA) 4G (LTE) Coolteq enables 4G transmissions using less power than today’s 3G PAs 9 Copyright © 2012 MIPI Alliance. All rights reserved. comparing traditional DC:DC converter and Coolteq. .9 ºC Envelope Tracking Output Power Dissipated Power (device) Measured Case Temperature 27.3 dBm 1180 mW 62.3 ºC 10 Copyright © 2012 MIPI Alliance.>50% reduction in PA heat dissipation simplifies thermal design Fixed supply voltage Average Output Power Dissipated Power (device) Measured Case Temperature 27. All rights reserved.3 dBm 487 mW 45. All rights reserved.7 GHz 11 Copyright © 2012 MIPI Alliance. .ET enables multiband PAs which ues less power than today’s 3G PAs 3 broadband ET PAs cover 700 MHz – 2. also being worked on in MIPI ACI 12 Copyright © 2012 MIPI Alliance.System Block Diagram MIPI RFFE Control Interface RF drive gain matching Shaping table Post-envelope gain & offset DAC Envelope Tracking Modulator Magnitude calculator Transmit System A B C Duplexer I-DAC Delay Balancing Q-DAC Power Amplifier To Antenna To Rxr • Digital logic overhead: ~50K gates in transceiver • Fast DAC needed– similar spec to I/Q DACs • Envelope Interface A – differential analogue interface • Specified by OpenET Alliance. . All rights reserved. PA efficiency and gain vary with supply voltage 13 Copyright © 2012 MIPI Alliance. . All rights reserved. All rights reserved. a digital LUT controls the “shape” of the supply voltage More gain Higher Efficiency 14 Copyright © 2012 MIPI Alliance.Under ET. . . All rights reserved.Nujira’s patented ISOGAIN™ ET linearizes the PA without requiring DPD Fixed supply Envelope Tracking • Result: 6-10 dB ACLR improvement • 2-3 dB more “linear power” • Deliver full power LTE to the antenna 15 Copyright © 2012 MIPI Alliance. ET delivers more power and cleaner signals. even into an antenna mismatch 16 Copyright © 2012 MIPI Alliance. . All rights reserved. So what’s so difficult about Envelope Tracking? • High power supply bandwidth requirement • 30-60 MHz for 20 MHz LTE • Very high slew rates • Low noise power supply • ACLR spec is “easy” to hit • RX-band noise (self desens) much harder • High efficiency ET supply modulator • Needs ~80% power conversion efficiency • ET<>PA supply feed is critical • ET chip replaces decoupling capacitor 17 Copyright © 2012 MIPI Alliance. . All rights reserved. Envelope Tracking ecosystem status • 12 of 14 platform chipset vendors are committed to include an Envelope Tracking interface • 4 with silicon now • 4 in silicon design phase • 4 at specification / architecture phase • All PA vendors have an active ETPA program • First stage: “ET Capable” PAs available now • Next step: “ET Optimised” PAs starting to show up • MIPI ACI working on interoperability standard • Expect ET-enabled reference platforms 2H2012 18 Copyright © 2012 MIPI Alliance. All rights reserved. . L Envelope Tracking chip for smartphones & terminals • Single chip ET supply modulator • 0.Coolteq. All rights reserved. MIPI RFFE Control Smartphone Chipset Envelope RF PA 19 .18u CMOS process • Replaces DC:DC converter to supply the RF PA • Supports 20 MHz LTE bandwidths Battery • Includes ET and APT operating modes • MIPI RFFE V1 control interface • OpenET analogue differential Envelope interface Copyright © 2012 MIPI Alliance. Thank you – Questions? 20 Copyright © 2012 MIPI Alliance. All rights reserved. .