Slide 1: GPRS pulses with cap-XX Supercapacitors
GPRS pulses with cap-XX Supercapacitors
Slide 2: The Problem – Battery devices
The Problem – Battery devices • GPRS pulses require high power for longer durations • Consequences Battery voltage droop during transmission resulting in premature low voltage shutdown Run time too short but plenty of energy left in the battery! 2 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 3: The Problem – PC, CF Cards
The Problem – PC, CF Cards • GPRS pulses require high power for longer durations • Consequences Average power drawn from host within specification But peak current too high ( 2A) PC Card Max = 1.0A, CF Card Max = 0.5A Break specification Non compliant device 3 cap-XX Copyright © 2002 by cap-XX
Slide 4: The Solution
The Solution Local Energy Storage device to provide Hi Power delivery for as long as needed • Hi Power + Hi Energy Storage • Low ESR + Very Hi C cap-XX supercapacitors solve this problem • 50-100m_ 100 – 800mF 4 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 5: Some demonstrations
Some demonstrations • Extended battery life • Reduced voltage droop • Power Averaging 5 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 6: Extended Battery Run Time
Extended Battery Run Time 4.5 4 3.6V 3.5 3.3V 3 14 3.0V mins 2.5 1h 9m 346% 10% 2 h 26 m 2h 40m 2 28 mins 1hr 37mins 32 mins 26% 1.5 2h 4m 2h 36m Battery run time and voltage Battery run time and 1 droop with no supercapacitor. voltage droop with Load was a GSM pulse train with 2A during transmit bu
Slide 7: Test Circuit for next 3 slides
Test Circuit for next 3 slides Electronic 10 ohms Load Li-Ion 3.7V 1 3 Load is GPRS 2 class 10 pulse cap-XX train, 2A for 8X470µf supercap 1.15msecs, 0A for Tantalum 380 mf 3.45msecs. 7 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 8: 600 mAh Battery, 2A GPRS Pulse
600 mAh Battery, 2A GPRS Pulse Referring to test 551mV circuit on slide 7 (previous slide) droop with Switch in position 2 battery alone 2A, 1.15msec GPRS class 10 pulse Battery current 8 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 9: 8 x Ta Capacitors, 2A GPRS Pulse
8 x Ta Capacitors, 2A GPRS Pulse Ta capacitors (470 F ea) have inadequate energy storage Referring to test circuit on slide 7 Switch in position 1 Min voltage improved by 160mV Peak Battery current ≈ 1.5A 9 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 10: cap-XX Supercapacitor
cap-XX Supercapacitor Supercapacitor enables the battery to be discharged a further 300mV Significant increase in run time Referring to test circuit on slide 7 Switch in position 3 Min Voltage improved by 302mV Supercapacitor averages load current. Peak battery current reduced to ≈ 0.9A 10 cap-XX Co
Slide 11: Summary
Summary • Hi peak power requirements cause power problems for both battery devices – Short run time • and hosted devices (PC, CF cards) – Break max current spec • Simple solution to both problems is a cap- xx supercapacitor Load averaging: Battery, host do not see peaks Hi energy storage and hi
Slide 12: Power Delivery for Notebooks with cap-XX Supercapacitors
Power Delivery for Notebooks with cap-XX Supercapacitors
Slide 13: The Problem – Notebooks
The Problem – Notebooks • Latest CPU’s can draw 100W transients • Consequences 10A load at the battery I2R losses in battery, 5%-10% Battery voltage droop of 1.5V Premature low voltage shutdown Run time too short but plenty of energy left in the battery! 13 cap-XX Copyright © 2002 by cap-XX
Slide 14: The Solution
The Solution Energy Storage device to provide Hi Power delivery for as long as needed Takes the power strain off the battery • Hi Power + Hi Energy Storage • Low ESR + Very Hi C cap-XX supercapacitors solve this problem • 30m_ 3F 14 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 15: Supercapacitor – transient suppressor
Supercapacitor – transient suppressor Source: Intel Developer Forum, Fall 2001, Intel Labs with SuperCap w/o SuperCap SuperCap Reduces Battery Transient by 7x 15 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 16: Supercapacitor – DVD Application
Supercapacitor – DVD Application with SuperCap w/o SuperCap POM 9x Ripple Battery Reduction Voltage Battery Current (1A per DIV) BOM 7x Ripple Reduction Source: Intel Developer Forum, Fall 16 2001, Intel Labs cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 17: Banias Program
Banias Program • cap-XX is working with Intel to evaluate the performance of supercapacitors with the next generation of high power CPU’s, starting with Banias • cap-XX will have available a daughter board for the Banias CRB to evaluate battery run time and supercapacitor performance 17 cap-XX Copyr
Slide 18: cap-XX battery evaluation PCB
cap-XX battery evaluation PCB 12V C AC Adapter R 12-25V Current 12V 5V 2.5V B Limit c Charger & 3.3V 1.5V o Battery n Selector Supercapacitor n 1.8V e c Batt Batt 12V to VRM t A B o Smart Battery Interface r The rails can be shutdown by the sleep states. 18 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 19: Summary and Next Steps
Summary and Next Steps n Latest CPU’s cause hi current transients and voltage droop at the battery Shortens run time • Premature Low Voltage Shutdown • Energy losses in battery impedance Very low impedance energy storage & power delivery device solves these problems Cap-XX supercapacitor Use
Slide 20: Back Up Slides
Back Up Slides 20 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 21: Test Circuit
Test Circuit Electronic 10 ohms Load Li-Ion 3.7V 1 3 2 cap-XX 8X470µf supercap Tantalum 380 mf 21 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 22: Demonstration details
Demonstration details • We apply a 2A pulsed load with three different time specifications: – GSM, 2 slot GPRS and 4 slot GPRS • To three different power sources: – A 600 mAh Li ion battery – The 600 mAh battery and 8 Ta capacitors, each 470 µF, 50 m – The 600 mAh battery and a cap-XX supercapacitor
Slide 23: Results for 2A GPRS 2 Slot pulses
Supercapacitor 1.9 x better than Ta in voltage cutoff Results for 2A GPRS 2 Slot pulses • 1/4 duty cycle • Voltage droop: • Battery 551 mV 600mAh Battery • Ta cap 160 mV less • cap-XX 302 mV less • Saves 142 mV 8 x Ta capacitors cap-XX supercapacitor 23 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 24: Results for 2A GPRS 4 Slot pulses
Supercapacitor 5.9 x better than Ta in voltage cutoff Results for 2A GPRS 4 Slot pulses • 1/2 duty cycle • Voltage droop: • Battery 561 mV 600mAh Battery • Ta cap 49 mV less • cap-XX 289 mV less • Saves 240 mV 8 x Ta capacitors cap-XX supercapacitor 24 cap-XX Copyright © 2002 by cap-XX Pty Ltd.
Slide 25: Results for 2A GSM pulses
Supercapacitor 1.3 x better than Ta in voltage cutoff Results for 2A GSM pulses • 1/8 duty cycle • Voltage droop: • Battery 547 mV 600mAh Battery • Ta cap 267 mV less • cap-XX 356 mV less • Saves 89 mV 8 x Ta capacitors cap-XX supercapacitor 25 cap-XX Copyright © 2002 by cap-XX Pty Ltd.