2007/04/10 ver.3 page 1 sp6850 green-mode pwm controller description applications the sp6850 is the current mode pwm controller with green-mode power-saving operation, to meet the low standby-power needs of low-power smps. this green-mode function enables the power supply to easily meet even the strictest power conservation requirements. the functions such as the leading-edge blanking of the current sensing, internal slope compensation and the small package provide the high efficiency / low cost for smps power applications. sp6850 is processed by bicmos fabrication, that enables reducing the start-up current and the operating current. sp6850 is available by sot-23-6l / dip-8p packages. z ac/dc switching power adaptor z battery charger z pc 5v standby power. z open-frame switching power supply features pin configuration sot-23-6l dip-8p part marking sot-23-6l dip-8p z high-voltage bicmos process z very low startup current (typ ~ 8a) z under voltage lockout (uvlo ) z current mode control with cycle peak z current limiting z leading-edge blanking z programmable switching frequency z internal slope compensation z green-mode control for power saving z non-audible-noise green mode control z 300ma driving capability z ovp (over voltage protection) on vcc pin
2007/04/10 ver.3 page 2 sp6850 green-mode pwm controller typical applcation circuit typical applcation circuit ( high efficiency smps + synchronous rectifier )
2007/04/10 ver.3 page 3 sp6850 green-mode pwm controller pin description sp6850d8tg pin symbol description 1 out gate driver output to drive the external mosfet 2 vcc supply voltage in 3 nc unconnected pin 4 cs current sense. this pin senses the voltage across a resistor, to control pwm output. this pin also provides current amplitude information for current-mode control. 5 rt this current is used to charge an intern al capacitor, to determine the switching frequency. 6 nc unconnected pin 7 comp voltage feedback. the pin provides the output voltage regulation signal., it provides feedback to the internal pwm comparator, so that th e pwm comparator can control the duty cycle. 8 gnd ground sp6850s26rg pin symbol description 1 gnd ground 2 comp voltage feedback. the pin provides the output voltage regulation signal., it provides feedback to the internal pwm comparator, so that th e pwm comparator can control the duty cycle 3 rt this current is used to charge an intern al capacitor, to determine the switching frequency. 4 cs current sense. this pin senses the voltage across a resistor, to control pwm output. this pin also provides current amplitude information for current-mode control 5 vcc supply voltage in 6 out gate driver output to drive the external mosfet block diagram
2007/04/10 ver.3 page 4 sp6850 green-mode pwm controller ordering information part number package part marking sp6850ad8tg dip-8p sp6850 i sp6850bd8tg dip-8p sp6850 i sp6850as26rg sot-23-6l 85ayw sp6850bs26rg sot-23-6l 850yw sp6850ad8tg / sp6850bd8tg : tube ; pb ? free sp6850as26rg / sp6850bs26rg : tape reel ; pb ? free absoulte maximum ratings (t a =25 , unless otherwise specified.) the following ratings designate persistent limits beyond which damage to the device may occur . symbol parameter value unit v cc dc supply voltage 36 v v comp / rt / cs comp / rt / cs voltage -0.3 ~ 7.0 v p d power dissipation @ t a =85 (*) 0.3 w human body model 4 kv esd machine model 300 v t ope operating ambient temperature -40 ~ 85 t j operating junction temperature range -40 ~ 150 t stg storage temperature range -40 ~ 150 t lead pb-free lead soldering temperature for 5 sec. 260 sot-23-6l 210 r ? jc thermal resistance junction ? case (*) dip-8p 95 /w (*) the power dissipation and thermal resistance are evalua ted under copper board mounted with free air conditions.
2007/04/10 ver.3 page 5 sp6850 green-mode pwm controller electrical characteristics (t a =25 , v cc =15v, unless otherwise specified.) symbol parameter conditions min. typ. max. unit supply voltage ( vcc pin ) i stt startup current 8 20 ua i op operating current v comp = 3v 2 4 ma uvlo (off) min. operating voltage 9.0 10.0 11.0 v uvlo (on ) start threshold voltage 15.0 16.0 17.0 v ovp level over voltage protection 28 36 v voltage feedback ( comp pin ) isc short circuit current 2.2 3.0 ma vop open loop voltage 5.0 v v th(gm) green mode threshold vcomp 2.35 v oscillator ( rt pin ) f osc frequency r t =100k ? 60.0 65.0 75.0 khz f osc(gm) green mode frequency fs=65.0khz 20 khz fdt frequency variation versus temp . deviation (-40c ~105c) 3 % fdv frequency variation versus v cc deviation (v cc =11v-25v) 1 % current sensing ( cs pin ) sp6850bd8tg sp6850bs26rg 0.8 0.85 0.9 vcs(off) maximum input voltage sp6850ad8tg sp6850as26rg 0.7 0.75 0.8 v zcs input impedance 50 k t pd delay to output 150 ns gate driver output ( out pin ) dc (max) maximum duty cycle 70 75 80 % dc (min) minimum duty cycle 0 % v ol output low level v cc =15v, io=20ma 1 v v oh output high level v cc =15v, io=20ma 8 v tr rising time load cap=1000pf 50 200 ns tf falling time load cap=1000pf 30 120 ns
2007/04/10 ver.3 page 6 sp6850 green-mode pwm controller performance characteristics (t a =25 , unless otherwis e specified.)
2007/04/10 ver.3 page 7 sp6850 green-mode pwm controller performance characteristics (t a =25 , unless otherwise specified.)
2007/04/10 ver.3 page 8 sp6850 green-mode pwm controller dip- 8p package outline
2007/04/10 ver.3 page 9 sp6850 green-mode pwm controller sot-23-6l package outline
2007/04/10 ver.3 page 10 sp6850 green-mode pwm controller information provided is alleged to be exact and consistent. sync power corporation presumes no responsibility for the penalties of use of such information or for any violation of pa tents or other rights of third parties that may result from its use. no license is granted by allegation or otherwise under any pate nt or patent rights of sync power corporation. conditions mentioned in this publication ar e subject to change without notice. this p ublication surpasses and replaces all information previously supplied. sync power corporation products are not authorized for use as critical components in life support devices or systems without express written approval of sync power corporation. ?the sync power logo is a registered trademark of sync power corporation ?2004 sync power corporation ? printed in taiwan ? all rights reserved sync power corporation 7f-2, no.3-1, park street nankang district (nksp), taipei, taiwan, 115, r.o.c phone: 886-2-2655-8178 fax: 886-2-2655-8468 http://www.syncpower.com
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