fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page1 primary-side-control cc/cv controller features description ? constant-current (cc) and constant-voltage (cv) control with primary side control ? 5% constant voltage regulation 10% constant current regulation ? eliminates opto-coupler and tl431 ? external power npn transistor for low cost ? built-in line compensation ? charger status indicator in primary side ? cycle-by-cycle current limiting ? over voltage protection (ovp) ? over temperature protection (otp) ? open circuit protection ? short circuit protection ? pb-free device typical application ? adapter/charger for cell/cordless phones, pdas, mp3 and other portable apparatus ? standby and auxiliary power supplies set top boxes (stb) the FT832DB controller device is optimized for high-performance, indicate charger status switching mode charger applications. the FT832DB integrated the charger status indicator in primary side, no need any devices for indicating the charger status in secondary side. the indicator integrated in FT832DB can be adjustable by a resistor between the pin cable and gnd .FT832DB facilitates cc/cv charger design by eliminating an opto-coupler and tl431. its highly integrated functions such as under voltage lockout (uvlo), leading edge blanking (leb), built-in line compensation, external power npn transistor offer the users a high efficiency and low cost solution for charger applications. furthermore, FT832DB features fruitful protections like otp (over temperature protection), ovp (over voltage protection), and open circuit protection, short circuit protection to eliminate the external protection circuits and provide reliable operation. FT832DB is available in sop8 packages. f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page2 typical application circuit figure 1: typical application circuit absolute maximum ratings fb to gnd???????????? ...??????????????.??. ???.????... -0.3v to +9v cs to gnd?????????? ??????...??????????? ????????.....-0.3v to +9v vcc to gnd?????????????..????.??????????????????-0.3v to +18v out to gnd???????????? ?...???????????.????...?. ????......-0.3v to +9v led_r to gnd??..?? ???????????????? ???.???.???.???......-0.3v to +18v led_g to gnd????..???? ?????????????? ?.??????.?..............-0.3v to +18v cable to gnd????? ???????????????? ???.????.????..?......-0.3v to +9v operating temperature ra nge????????...????????????????...?...-40 to +125 junction temperature?????? ??????..??????????? ??????..... -40 to +150 storage temperature range ???????????..???????????????.?.-60 to +150 esd protection hbm??????.....???? ????????????????????.???.2000v mm???????..??????????????????????????...500v stresses exceeding maximum ratings may damage the device. maximum ratings are stress ratings only. functional operation above the reco mmended operating conditions is not implied. extended exposure to stresses above the recommended operating conditions may affect device reliability . f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page3 pin configuration figure 2: pin assignments pin definition pat no. package 1 2 3 4 5 6 7 8 FT832DB sop8 led_g led_r vcc out gnd fb cs cable table 2: pin definition terminal definition pin description gnd ground. fb output voltage feedback pin cs primary current sense vcc supply voltage out npn switch base driver led_r connect to red led for indicating charging state led_g connect to green led for indicating charge completed state cable adjust cable compensation by an exte rnal resistor and capacitor to gnd table 3 ordering information FT832DB x ? xx package temperature range hsf packaging ordering code tube FT832DB-rb rohs tape and reel FT832DB-rt tube FT832DB-gb sop8 -40 -125 green tape and reel FT832DB-gt table 4 circuit type package blank: sop8 hsf and packaging rb: rohs and tube rt: rohs and t&r gb: green and tube gt: green and t&r f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page4 marking rule figure 3: marking rule sop8: : represents version (db) ??? : for internal reference block diagram driver q q set clr s r cv controller comp 0.5v leb 400ns cc controller ea 3v ccm protection vdd comp 4.65v q q set clr s r por delay 3us band gap ldo ref internal reference &bias por gnd out cs fb vcc uvlo otp 150ua 12.1/5.1v comp 0.1v 3 x (1+kcab)v vline vcc_on/vcc_off fb_open ovp vcs vovp vfb ifb_open otp ifb loading detect cable charging status controller led_g led_r vdd ibias vcp figure 4: FT832DB block diagram f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page5 electrical characteristics ( for typical values tj=25 , vcc=14v, unless otherwise noted ) characteristic symbol min typ max unit current sense maximum current threshold vcs_max 0.49 0.5 0.51 v pre-drive current threshold vcs_pre 0.44 0.45 0.46 v vcs_limit temperature stability (-40 ~125 ) 1 % leading edge blanking duration tleb 400 ns propagation delay (out=1.0nf to gnd) tpd 200 ns feedback section feedback voltage threshold vfb 2.97 3 3.03 v fb pin minimum current ifb_open 50 a ovp protection threshold level vovp 4.55 4.65 4.75 v ccm protection threshold level vcp 0.1 v supply section start up threshold voltage vcc_on 13.5 15 17.2 v under voltage lockout voltage vcc_off 4.8 5.4 6 v vcc start up current istart_up 6 ua operating current iop 1.1 ma protection section feedback loop open protection ifb_open 150 ua over temperature protection tsd 140 over voltage protection v_ovp 18.5 v base driver output maximum sink current isink 50 ma output maximum source current isource 28 ma compensation line compensation (ifb=1ma) vline 45 mv table 5 f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page6 electrical characteristics (continues) characteristic symbol min typ max unit led section threshold level of the red led lighting turn to green led lighting (kcab2=8560/r7 *1 10e+3) kcab2 *3 kcab2 % threshold level of the green led lighting turn to red led lighting kcab3 *4 kcab2+2 % the maximum sink current for led_r imr 10 ma the maximum sink current for led_g img 10 ma the leakage current for led_r ikr 1 ua the leakage current for led_g ikg 1 ua table 5 *1 (r7): resistor connected between pin cable and gnd *3 (kcab2): the rate of the loading current when red led lighting turn to green and the maximum loading current . *4 (kcab3): the rate of the loading current when green led lighting turn to red and the maximum loading current . f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page7 functional description operating description FT832DB are cost effective and hi gh-performance ac-dc power supply controller for off-line low power ac-dc applications including battery chargers and adaptors. without seconda ry feedback circuit, the constant voltage (cv) and constant current (cc) control can be achieved accurately. start up control start-up current of FT832DB is very low so that a start-up resistor with high resistance and low-wattage is allowed to supply the start-up power for the cont roller. the large value startup resistor can minimize the power loss in application and starts up quickly. a 1.5mo, 0.25w start-up resistor and a 10uf/25v vdd hold-up capacitor are sufficient for an ac-to dc power adapter. operating current the operating current of FT832DB is as low as 1ma. good efficiency is achieved with the low operating current together with valley turn on of the external power npn transistor. low operating current also reduces the vcc hold-up capacitance requirement. constant voltage (cv) and constant current (cc) operation the FT832DB can accurately achieve cv/cc characte ristic output without secondary side voltage and current-feedback circuits. it operates in cv m ode to regulate the output voltage by capturing the auxiliary winding feedback voltage at fb pin. the aux iliary winding feedback voltage is proportional to secondary winding, so it provides controller the feedback signal from secondary side and achieves constant-voltage output. in cc mode, the controller de tects the secondary discharger peak current and the discharger time, which determines the off-time of the base driver to make the output average current constant. in the cv or cc mode, the primary side peak current is constant if the rcs is settled. leading edge blanking each time the power npn transistor is switched on, a turn-on spike occurs at the sense resistor. to avoid premature termination of the switching pulse , a 400ns leading edge blanking time is built in. conventional rc filtering can therefore be omitted. during this blanking period, the current limit comparator is disabling and cannot switch off the base driver. under voltage lockout (uvlo) FT832DB turn-on [vcc(on)] and turn-off [vcc(off)] are 15v and 5.4v. during start-up, the hold-up capacitor must to be charged to 15v through the star t-up resistor. the hold-up capacitor continues to supply vcc until power can be delivered from the auxilia ry winding of the transformer. vcc must not drop below 5.4v during this start-up process. this uvlo hysteresis window ensures that hold-up capacitor is sufficient to supply vcc during start-up. protection control with rich protection features of FT832DB, a good power supply syst em reliability is achieved. the protection features including cycle by cycle current limiting, vcc over voltage protection and clamp, f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page8 short circuit protection, feedback loop open protection, over temperature protection and under voltage lockout on vcc. led charge indicator a proprietary led charge indicator is integrated in FT832DB. in charger application, FT832DB can indicate the charge status by connecting red led and green led to led_r pin and led_g pin. the red led indicates charging, the green led light means the completion of charging. f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page9 sop8 package outline dimensions dimensions in millimeters dimensions in inches symbol min max min max a 1.350 1.750 0.053 0.069 a1 0.100 0.250 0.004 0.010 a2 1.350 1.550 0.053 0.061 b 0.330 0.510 0.013 0.020 c 0.170 0.250 0.006 0.010 d 4.700 5.100 0.185 0.200 e 3.800 4.000 0.150 0.157 e1 5.800 6.200 0.228 0.244 e 1.270 (bsc) 0.050 (bsc) l 0.400 1.270 0.016 0.050 0 8 0 8 f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
fremont micro devices FT832DB ? 2012 fremont micro devices inc. ds832db-a0-page10 fremont micro devices (sz) limited #5-8, 10/f, changhong building, ke-ji nan 12 road, nanshan district, shenzhen tel: (86 755) 86117811 fax: (86 755) 86117810 fremont micro devices (hong kong) limited #16, 16/f, blk b, veristrong industrial centre, 34- 36 au pui wan street, fotan, shatin, hong kong tel: (852) 27811186 fax: (852) 27811144 fremont micro devices (usa), inc. 42982 osgood road fremont, ca 94539 tel: (1-510) 668-1321 fax: (1-510) 226-9918 web site: http://www.fremontmicro.com/ * information furnished is believed to be accurate and reliable. however, fremont micro devices, incorporated (bvi) assumes no responsibility for the c onsequences of use of such information or for any infringement of patents of other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent rights of fremont micro devices, incorporated (bvi). specifications mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information previously supplied. fremont micro devices, incorporated (bvi) products are not authorized for use as critical com ponents in life support devices or systems without express written approval of fremont micro devices, incorporated (bvi). the fmd logo is a registered trademark of fremont micro devices, incorporated ( bvi). all other names are the property of their respective owners. f o r f r e m o n t m i c r o u s a r e f e r e n c e o n l y .
|
