www.belling.com.cn 1 18v (30v spike) 2a synchronous buck converter bl 9382 description the BL9382 is a high efficiency current - mode synchronous, 18v/2a buck converter. its input voltage ranges from 4.5v to 18v and it provides an adjustable regulated output voltage from 0.923v to 15v while delivering up to 2a of output current. the internal synchronous switches increase efficiency and eliminate the need for an external schottky diode. the switching frequency is set to 340khz. BL9382 consists of many protection block such as uvlo, input voltage over voltage protection to stand m uch higher input voltage spike, thermal protection and output short circuit protection. the BL9382 is available in the sop8 and esop8 (with exposed pad for heat dissipation) package features ? adjustable output voltage, vfb=0.923v ? maximum output current i s 2a ? range of operation input voltage: max 18v ? withstand input voltage spike >30v ? standby current: 1ma (typ.) ? operating current at zero load: 1.2ma (typ.) ? line regulation: 0.1 %/v (typ.) ? load regulation: 10mv (typ.) ? high efficiency, up to 95% ? input ovp at 20v ? environment temperature: - 20 ? c ~85 ? c applications ? set - top - box ? consumer electronic device for automobile ? lcd monitor and lcd tv ? portable dvd ? adsl modem, wlan router ? other 12v or double cell li - ion battery powered device typical application pin out sop8 and esop8 BL9382 l c 2 3 2 1 b s t v i n s w g n d s s e n c o m p f b 1 0 u h v i n 1 0 u f 1 0 n f 0 . 1 u f 1 0 0 k 3 . 3 n f 5 . 6 k v o u t 3 . 3 v / 2 a 2 2 u f x 2 2 6 . 1 k 1 0 k * c c o p t i o n a l * w h e n v i n i s a s l o w a s 5 v , c c i s r e c o m m e n d e d t o b e 1 0 0 p f , b u t n o t n e e d e d w h e n v i n l a r g e r t h a n 5 v .
www.belling.com .cn 2 bl 9382 mark and ordering information mark explanation ordering information xx : year yy : week zz : internal code sop8 2500pcs/reel BL9382 cd8tr esop8 2500pcs/reel BL9382 cs8tr pinout description pin # name description 1 bst high side power transistor gate drive boost input 2 vin power input, the input capacitor should be placed as close to vin and gnd pin as possible 3 sw power switching node to connect inductor 4 gnd ground. 5 fb feedback input with reference voltage set to 0.923 6 comp compensation node. a serial rc connected to this pin is required to maintain the buck converter control loop stable. 7 en enable input. setting it to high level or connecting to vin via a resistor may turn on the chip, while setting it to ground level will turn off the chip. 8 ss soft - start node. connecting a 0.1uf capacitor to ground make the buck converter output rise smoothly. block diagram + - 0 . 9 2 3 v r e f p w m l o g i c a n t i - s h o o t - t h r o u g h d r i v e r + - e a + - + - s l o p e c o m p o s c s w g n d u v l o & t h e r m a l s h u t d o w n v c o m p i s e n s e c o m p c o m p n e t w o r k f b e n v i n b s t 5 v s s
www.belling.com .cn 3 bl 9382 absolute maximum rating parameter value max input voltage 30v max operating junction temperature(tj) 125 ? c ambient temperature(ta) - 20 ? c C 85 ? c package thermal resistance ( ? jc) sop - 8l 45 ? c / w esop - 8l 10 ? c / w storage temperature(ts) - 40 ? c - 150 ? c lead temperature & time 260 ? c , 10s esd (hbm) >2000v note: exceed these limits to damage to the device. exposure to absolute maximum rating conditions may affect device reliability. recommended work conditions parameter value input voltage range max. 18v operating junction temperature(tj) - 20 ? c C 125 ? c electrical characteristics (vin=12v, t a =25 ? c) symbol parameter conditions min typ max unit vdd input voltage range 4.5 18 v uvlo_up uvlo,in uvlo rising record vin pin voltage as v(uvlo) when measure i(in)> 500ua 3.8 4.1 4.4 v vref feedback voltage vin=12v, ven=5v 0.900 0.923 0.946 v ifb feedback leakage current 0.1 0.4 ua iq quiescent current active, vfb=1v, no switching 1.1 1.5 ma shutdown, vin=8v 6 10 ua lnreg line regulation vin=5v to 12v 0.1 %/v ldreg load regulation iout=0.1 to 2a 0.02 %/a fsoc switching frequency ven=2v, vin=12v 340 khz rdsonp pmos rdson 130 mohm rdsonn nmos rdson 110 mohm ilimit peak current limit 2.5 a venh en high threshold 1 1.5 2 v venl en low threshold 0.5 v vovp input over - voltage protection ven=2v 18 v tsd over temperature proection 160 ? c
www.belling.com .cn 4 bl 9382 typical performance characteristics (vin=12v, vout=3.3v, l=10uh, cin=10uf, cout=22uf, t a =25 ? c, unless otherwise stated) f ast t ransient response startup through enable shutdown through enable short circuit recovery switching waveform vin=18v, iout=0 switching waveform vin=18v, iout=2a vin vout sw i_l vin vout sw i_l
www.belling.com .cn 5 bl 9382 switching waveform vin=5v, iout=0 switching waveform vin=5v, iout=2a functional decriptions loop operation the BL9382 is a wide input range, high - efficiency, dc - to - dc step - down switching regulator, capable of delivering up to 2a of output current, integrated with a 110m ? synchronous mosfet, eliminating the need for external diode. it uses a pwm current - mode control schem e. an error amplifier integrates error between the fb signal and the internal reference voltage. the output of the integrator is then compared to the sum of a current - sense signal and the slope compensation ramp. this operation generates a pwm signal that modulates the duty cycle of the power mosfets to achieve regulation for output voltage. current limit there is a cycle - by - cycle current limit on the high - side mosfet of 3a(typ). when the current flowing out of sw exceeds this limit, the high - side mosfet turns off and the synchronous rectifier turns on. unlike the traditional method of current limiting by limiting the voltage at the compensation pin, which usually has large variation due to duty cycle variance, this type of peak current limiting scheme pro vides a relatively more accurate limit for output current, thereby lowering the requirements for system design. faster transient response normally, people use 3.3nf and 5.6kohm rc for compensation to keep the loop stable. howev er, if one needs to have faster load transient response, 3.3nf and 8.5kohm is recommended. vin vout sw i_l vin vout sw i_l
www.belling.com .cn 6 bl 9382 component selectrion when setting up the BL9382 for different output voltage, please use following recommended component value for the best performance. v out (v) c out ( ? ? thermal consideration BL9382 is high efficiency buck converter, which means it consumes very few power when converting the high voltage to low voltage. however, when output power is very large, like 5v/2a, the output power is as high as 10w, a heat dissipation path is strongly recomm ended to be routed on pcb. BL9382 has two different sop8 package. for the normal sop8, the heat is conducted out via pin 4 (gnd), so the heat dissipation route on pcb should be connected to the pin 4 of the chip. if esop8 is selected, the heat dissipation copper area should be exposed and connected to the exposed pad underneath the chip body. when output power is larger than 10w, the esop8 package is recommended.
www.belling.com .cn 7 bl 9382 package outline package sop8 devices per reel 2500 unit mm package specification package esop8 devices per reel 2500 unit mm package specification
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