preli minary eum6867 ds 6 867 ver0.1 nov. 2007 1 p w m pre driver for dc fan motor des crip tion eum686 7 i s a pre driver for single coil brushless dc motor, specially designed for 12v power supply application. with an external pwm input signal, eum6867 can control the speed of dc motor. it is an interface between a hall ic and a single coil motor. the functions built in eum6867 include soft start mode, pwm control mode, minimum speed mode, soft-switching time, fan tachometer, lock protection, auto restart, hall bias and current limiter. pwm mode controls the external pmos-nmos fet in low noise and low vibration. with soft start function. eum6867 can drive motor from slow speed to fast speed in a settable time by setting the external capacitor between s-s and 5vreg. minimum speed mode makes the lowest speed of motor settable. soft-switching time can cut the ineffective current when phase change is not set. if the motor is stalled by external force or obstacles, overdrive current may incur coil overheat/burning. to prevent this, lock protection circuit can shut down the external power devices for a few seconds after motor lockup. then auto restart circuit will try to power up these devices. the protection and power up time are settable by an external capacitor. eum6867 has fg output. applic at ion circuit fe at ures z single-phase full - wave pre driver z pwm control mode z soft start function z soft-switching time z minimum speed settable z lock protection and auto restart z fg output z current limit protection z available in tssop-16 package z rohs compliant and 100% lead (pb)-free appl icat ions z p ersonal computer?s power supply radiation and cpu cooler figur e 1. v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 2 pin configurations package type pin configurations tssop-16 pin description pin tssop-16 description out2p 1 output terminal for external upper side power device out2n 2 output terminal for external lower side power device vcc 3 power supply terminal sense 4 motor current sense terminal rmi 5 motor lowest speed setup terminal vth 6 motor speed control terminal cpwm 7 external capacitor connection terminal for pwm osc fg 8 rotation speed feedback terminal in- 9 hall input terminal in+ 10 hall input terminal ct 11 lock protection time setup terminal s-s 12 soft start setting terminal 5vreg 13 5v regulator sgnd 14 ground terminal out1n 15 output terminal for external lower side power device out1p 16 output terminal for external upper side power device n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 3 ordering information order number package type markin g operating temperature range EUM6867QIR1 tssop-16 xxxxx eum6867 -30 to 90 eum6867 ?? ?? ?? ?? lead free code 1: lead free 0: lead packing r: tape & reel operating temperature range i: industry standard package type q: tssop block diagram figure 2. n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 4 absolute maximum ratings ? vcc ------------------------------------------------------------------------------------------------- 18v ? ioutn--------------------------------------------------------------------------------------------- 20ma ? ioutp--------------------------------------------------------------------------------------------- 20ma ? vout ---------------------------------------------------------------------------------------------- 18v ? vth,rmi ------------------------------------------------------------------------------------------ 7v ? vs-s ------------------------------------------------------------------------------------------------ 7v ? vfg ------------------------------------------------------------------------------------------------- 18v ? ifg ------------------------------------------------------------------------------------------------ 10ma ? i5vreg------------------------------------------------------------------------------------------- 20ma ? power dissipation -------------------------------------------------------------------------------- 0.8w ? operating temperature --------------------------------------------------------------- -30 j to 90j ? storage temperature ----------------------------------------------------------------- -55
to 150
recommended operating conditions at ta = 25c ? supply voltage, vcc -------------------------------------------------------------------- 4.5v to 16v ? vth and rmi input voltage range --------------------------------------------------- 0v to 5v ? hall input voltage range ---------------------------------------------------------------- 0.2v to 3v ? osc voltage range ----------------------------------------------------------------------- 0.2v to 3v electrical characteristics ( unless otherwise specified t a =25c, vcc = 12v ) eum6867 parameter conditions min. typ. max. unit icc1 rotation mode 10 icc2 supply current drain lock protection mode 10 ma hall input vhn input hysteresis voltage zero to peak (offset & hysteresis included) 10 mv output vonh outn output high voltage output current of out-n= 10ma vcc- 0.9 v vonl out-n output low voltage output current of out-n= 10ma 0.9 v vopl out-p output low voltage output current of out-p = 10ma 0.5 v voltage reference 5vreg 5v regulator i5vreg = 5ma 5 v pwm block fpwm cpwm oscillation frequency c = 220pf 30 khz vlim current limit voltage 200 mv vcrl cpwm low voltage 1 v vcrh cpwm high voltage 3 v lock protection block ict1 ct charge current vct = 0.5v 2 ga ict2 ct discharge current vct = 3.5v 0.2 ga rct ratio of charge current to discharge current rct = ict1 / ict2 10 - vcth ct high level voltage 3 v vctl ct low level voltage 1 v n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 5 electrical characteristics (continued) ( unless otherwise specified t a =25c, vcc = 12v ) eum6867 parameter conditions min. typ. max. unit lock protection block is-s s-s pin charge current vs-s=1v 0.5 ga fg signal output vfgl fg low voltage ifg = 5ma 0.15 v ifgl fg leakage current vfg = 19v 30 ga ivth/ irmi vth/rmi pin bias current cpwm=vth/rmi=2v 0.1 ga * this product is not designed for protection against radioactive rays. n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 6 notes absolute maximum ratings this product is produced with strict quality control, but destroyed in using exceed the absolute maximum ratings. once ic destroyed, failure mode cannot be defined (like short-mode or open-mode). therefore, physical security countermeasure, like fuse, is to be given when a specific mode to exceed the absolute maximum ratings is considered. sgnd potential the sgnd terminal should be the location of the lowest voltage on the chip. mounting failures mounting failures, such as misdirection or mismount, may destroy the device. the electrical short caused by falling particle, between outputs; power supply and output; or output and ground, may damage the device. electromagnetic field a strong electromagnetic field may cause malfunction. aso please consider output transistors not to exceed absolute maximum ratings. hall signal input terminals (in+ ?bin-) figure 3. hall input voltage range figure 4. hall element hall input signal should contain voltage within range 0.2v to 3v. so, please adjust hall input level by r1. in the case of long board wiring pattern from hall element to hall signal input terminal, please connect capacitor between in+ and in- to avoid noise. the amplitude of hall input signal is recommended to be 100mvp-p or bigger, because the hall input amplifier has 20mvp-p hysteresis and has the soft switching range of 35mv (the input difference voltage). vcc line the capacitor about 0.1 g f or bigger between vcc and ground is recommended to absorb kick back voltage. because of upper side pwm control, the re-circulation current is in the external lower side power device. sgnd line divides each line and external parts of control stage are connect to sgnd. zener diode of re-circulation stability because kickback can increase the power supply voltage, a zener diode is recommended to avoid ic destroy. pwm osc frequency the pwm osc frequency is settable by value of cp witch is connected between cpwm and gnd. using 220pf cp can get frequency of 30 khz. lowest speed settable lowest speed of motor is set by input voltage of rmi. connect rmi to vth (or to 5vreg with a resistor of 10k) when this function is not used. when ic power supply may turn off first, please put a resistor for current limitation between external power supply and rmi to prevent large current from flowing. soft start time a capacitor is connected between s-s and 5vreg. soft start time can be set by the capacitance of capacitor. please connect this pin to ground when this pin is not used. soft start time function will drive motor from slow speed to fast speed in a settable time by external cap between s-s and 5vreg. current limiter when sense pin voltage is over 0.2v, output current for motor will be shut down. connect sense to ground when this function is not used. n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 7 truth table pwm control mode (ct, s-s=low) vth rmi cpwm in+ in- out1p out1n out2p out2n motor current mode l h l l off h out1 ? out2 l h h l off h l l out2 ? out1 l h off l off h h l h l off h off l rotation re-circulation drive-lockup (cpwm=high vth,rmi,s-s=low) in+ in- ct out1p out1n out2p out2n fg motor current mode l h l l off- h l out1 ? out2 h l l off h l l off out2 ? out1 l h off l off h l h l h off h off l off lock protection control timing chart (speed control) figure 5. 1. lowest speed setting mode (stop mode) lowest speed of motor is settable by rmi pin. when vth voltage is bigger than rmi, the lowest drive duty is settable by comparing rmi and cpwm oscillating voltage. fan motor will stop when minimum speed is not set by the rmi pin. 2. pwm control speed mode through comparing the voltage of vth and cpwm, which is 1.0v to 3.0v, pwm control mode works. upper and lower sides power devices will be turned on to charge the motor coil when vth is low. and upper side power devices will be turned off and the current in motor coil will re-circulate in lower side power devices when vth is high. the lower vth is, the bigger the output on duty becomes. big coil current makes motor run fast. fg output feedbacks motor rotational speed. 3. full speed mode the motor coil is charged all the time and motor speed becomes full speed when vth voltage is lower than 1.0 v. if pwm-in opens, vth will become lower than 1.0v, output becomes full speed mode. n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 8 control timing chart (soft start) 1. vth voltage < rmi voltage figure 5. figure 6. 2. vth voltage > rmi voltage figure 7. the inclination of s-s voltage is adjusted according to the capacitor between s-s and 5vreg. recommended capacitor: 0.1 ?? 1.0. n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 9 lock protection and auto restart when motor lock is detected, the output will be turned off by lock protection function. after a few seconds, auto restart circuit will try to start motor. if motor start fail (still lo ckup), another lock protection will be turned off output for a fe w seconds until next restart time comes. figure 8. n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
preliminary eum6867 ds6867 ver0.1 nov. 2007 10 packaging information tssop-16 millimeters inches symbols min. max. min. max. a - 1.20 - 0.047 a1 0.00 0.15 0.000 0.006 b 0.19 0.30 0.007 0.012 e1 4.40 0.173 d 5.00 0.197 e 6.20 6.60 0.244 0.260 e 0.65 0.026 l 0.45 0.75 0.018 0.030 n ~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? w w w . g o f o t e c h . c o m
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