step-down dc/dc converters(non-isolated) BP5220A / bp5221a / bp5222a the BP5220A, bp5221a, bp5222a, are dc / dc converters that use a pulse width modulation (pwm) system. they contain control circuits, switching devices, rectifiers, and coils, and operate by only connecting an i / o smoothing capacitor. with a high efficiency of power conversion, the modules are available in stand-alone 9-pin sip packages with no heat sink required. they can be applied to various purposes by fine-tuning the output voltage and switching on and off. with a wide range of input voltage, the modules are best suited for obtaining a stable local power supply from a main power supply with a large voltage variation. applications description power supplies for copiers, personal computers, facsimiles, av equipment, measuring instruments, vending machines, security device, registers, industrial equipment, and maintenance tools features 1) wide input voltage range 2) high power conversion efficiency. 3) built-in output on / off switch. 4) adjustable output voltage ensures wide compatibility 6) heat sink unnecessary. 7) compact package. BP5220A / bp5221a / bp5222a : sip9 lineup absolute maximum ratings (ta=25 c) BP5220A bp5221a bp5222a BP5220A bp5221a bp5222a input voltage 8 to 38 8 to 38 15 to 38 v output voltage 5 5 12 v output current output current 1 0.5 0.5 a power conversion efficiency 84 (vi=15v) 90 (vi=20v) 85 (vi=15v) % unit limits parameter symbol unit input voltage vi 8 to 38 8 to 38 15 to 38 v i o 1 0.5 0.5 a c operating temperature range to p r storage temperature range tstg c 5) few external components required. sip9 1 28.0 max. 19.5 max. 41 pin no. 2.54 0.5 1.4 2.54x 8=20.32 234567 9 4.0 8.0 max. 12.0 max. max. marked side note : dimensions without tolerance is typical. marked side dimensions (unit : mm) 1/7 2010.03 - rev. b www.rohm.com ? 2010 rohm co., ltd. all rights reserved. data sheet
data sheet BP5220A/bp5221a/bp5222a drive circuit control circuit power supply circuit vi 9 7654321 adj ctl gnd v out fb BP5220A / bp5221a / bp5222a n. c. n. c. n. c. parameter symbol unit conditions min. typ. max. input voltage vi 8 38 output voltage v o 4.75 5 5.25 output current i o 1 line regulation 27 80 vi=8v to 38v vi=8v to 38v load regulation 13 80 io=0.1a to 1a io=0.05a to 0.5a output ripple voltage 22 70 power conversion efficiency 75 85 io=1a io=1a switching frequency f sw 190 ctl pin on resistance r on 4.7 vo>4.75v vo>4.75v ctl pin off resistance input voltage output voltage output current line regulation load regulation output ripple voltage power conversion efficiency switching frequency ctl pin on resistance ctl pin off resistance r off 200 vo<0.1v, sw=2 vo<0.1v, sw=2 symbol vi v o i o f sw r on r off vi<30v bp5221a (unless otherwise noted : vi=15v, io=0.25a, sw=1, ta=25?c) parameter unit conditions min. typ. max. 8 38 v 4.75 5 5.25 v 0.5 a 13 50 mv 350mv 25 70 mv pp 70 84 % 190 khz 4.7 200 v v a mv mv mv pp % khz BP5220A (unless otherwise noted : vi=15v, io=0.5a, sw=1, ta=25?c) block diagram electrical characteristics 2/7 2010.03 - rev. b www.rohm.com ?2010 rohm co., ltd. all rights reserved.
data sheet BP5220A/bp5221a/bp5222a bp5222a (unless otherwise noted : vi=20v, io=0.25a, sw=1, ta=25?c) t output ripple voltage please note that output ripple voltage depends on the type and characteristics of the output capacitor. switching frequency=1/t fig.1 + + 9 7654321 input a vv a f sw 12 output 4.7k 200k BP5220A / bp5221a / bp5222a f ; frequency counter vi=15v to 38v io=0.05a to 0.5a io=0.5a vo>11.2v input voltage output voltage output current line regulation load regulation output ripple voltage power conversion efficiency switching frequency ctl pin on resistance ctl pin off resistance vo<0.1v, sw=2 symbol vi v o i o f sw r on r off parameter unit conditions min. typ. max. 15 38 v 11.2 12 12.8 v 0.5 a 22 50 mv 18 50 mv 29 70 mv pp 75 90 % 190 khz 4.7 200 measurement circuit 3/7 2010.03 - rev. b www.rohm.com ?2010 rohm co., ltd. all rights reserved.
data sheet BP5220A/bp5221a/bp5222a circuit operation (1) the basic application examples are shown in fig.2. the only external parts required are the input and output smoothing capacitors. (2) switching on and off the output voltage is allowed. the output can be switched off by making pin 4 open (high impedance). (see fig.3) (3) fine adjustment of the output voltage is allowed. adjustment of the output voltage can be performed from pin 6 via the resistor by connecting the output terminal (pin 2) or gnd. (see application example 3) application examples application example 1 : dc / dc converter with protection circuit fig.3 120pf comp. + ba10393 vi 24v v o 5v 9 7654321 BP5220A / bp5221a / bp5222a + + fig.4 vi = 24v 0.2 0.4 0.6 0.8 1.0 1.2 6 5 4 3 2 1 0 output current (a) output voltage (v) fig.5 fig.6 a resistor is used to limit the rise of output at power on. the resistance depends on the input voltage. this is a standard application. because the control current fluctuates with variations in circuits and components, set the control current by adding a sufficient margin to the normal current level. 97654321 vi v o BP5220A / bp5221a / bp5222a + + fig.2 be sure to use fuse for safety. 9 7654321 vi sw v o BP5220A / bp5221a / bp5222a output off + + be sure to use fuse for safety. application example 2 : output on / off control 9 7654321 vi v o 470 f 100k 100k 2sc1740 BP5220A / bp5221a / bp5222a on / off 100 f + + be sure to use fuse for safety. 4/7 2010.03 - rev. b www.rohm.com ? 2010 rohm co., ltd. all rights reserved.
data sheet BP5220A/bp5221a/bp5222a application example 3 : output voltage adjustment (1) when reducing the output voltage vr value setting equations (the output voltage after adjustment is denoted by vo.) (1) when reducing the output voltage BP5220A / bp5221a bp5222a (2) when increasing the output voltage BP5220A / bp5221a bp5222a to maximize performance we recommended the output voltage be adjusted within 20% of the output voltage rating. when the output voltage is increased by 20%, for instance, the minimum input voltage is also increased by 20%. (example : when the output voltage is changed from 5v to 6v in the BP5220A, the minimum input voltage is charged from 8v to 9.6v) (2) when increasing the output voltage fig.7 fig.9 application example 4 : slow start the slow start circuit mitigates the pulse load on the internal switching transistor when input voltage is applied, and increases the output voltage gradually by starting the switching operation slowly. this application is useful for preventing malfunction of an external protection circuit due to rush current, and can serve as a countermeasure against operation outside the safe operation range. c1 is a slow-start capacitor for mitigating excessive rush current that flows into the module when the switch is turned on. vi 9 7654321 vr BP5220A / bp5221a / bp5222a v o + + be sure to use fuse for safety. 9 7654321 470 f vr v o BP5220A / bp5221a / bp5222a + fig.8 100 f vi + be sure to use fuse for safety. 9 7654321 v o 470 f 100k c1 10 f vi 24v 470k BP5220A / bp5221a / bp5222a 2sc1740r 100 f + + + be sure to use fuse for safety. 5/7 2010.03 - rev. b www.rohm.com ? 2010 rohm co., ltd. all rights reserved.
data sheet BP5220A/bp5221a/bp5222a (1) no circuit is installed in the modules to protect against excessive output currents. therefore, take physical safety measures such as using a fuse if short-circuit loading is probable. (2) the output current should be reduced according to an increase in the input voltage or ambient temperature. use the modules within the derating curve range. (3) a large rush current may flow in the module when the input voltage is applied or the output on / off is controlled with pin 4 without a capacitor such as c1 in application 4. operating within the safe operation ranges shown in fig.12, 15, and 18. the safe operation range is determined by the safe operation range of the internal switching transistor. the amount of rush current depends on the output impedance of the input power supply and capacitors connected to the module outputs. the pulse load on the internal switching transistor at the start of operation can be reduced by using the protection circuit in application 1 or the slow start circuit in application 4. (4) pins 5 and 7 are not connected. (5) a smoothing electrolytic capacitor is necessary for i/o external components. please use a capacitor equivalent to the recommended one. (6) please put an i/o smoothing capacitor near the module. output ripple voltage may be larger or output voltage may not be stable. BP5220A bp5221a 0255070 1000 800 600 400 200 output current : i o (ma) ambient temperature : ta( c) 100 120 0 25 50 70 100 120 1200 vi=8 to 15v vi=34v vi=38v vi=25v vi=30v fig.10 derating curve output current : i o (ma) ambient temperature : ta( c) fig.13 derating curve 100 80 60 40 20 0 200 400 600 800 1000 output current : i o (a) vi=8v vi=23v vi=38v fig.11 efficiency output current : i o (a) fig.14 efficiency 20 10 5 3 2 1 0.5 0.3 0.2 0.1 1 2 3 5 10 20 30 50 pw=0.2ms pw=1ms voltage between pin2 and pin9 (v) output current into pin9 (a) tc=25 c single pulse fig.12 safety operation range voltage between pin2 and pin9 (v) output current into pin9 (a) fig.15 safety operation range 0.5 0.4 0.3 0.2 0.1 vi=30 to 38v vi=8 to 15v 0.6 100 80 60 40 20 0 0.1 0.2 0.3 0.4 0.5 vi=8v vi=23v vi=38v 10 4.5a 2.2a 1 0.1 1 10 100 pw=1ms pw=10ms operation notes electrical characteristics curves tc=25 c single pulse 6/7 2010.03 - rev. b www.rohm.com ? 2010 rohm co., ltd. all rights reserved.
data sheet BP5220A/bp5221a/bp5222a bp5222a 0255070 0.5 0.4 0.3 0.2 0.1 100 120 0.6 vi=15 to 20v vi=30v vi=38v fig.16 derating curve 100 80 60 40 20 0 0.1 0.2 0.3 0.4 0.5 vi=30v vi=23v vi=38v fig.17 efficiency + 97 + 654321 BP5220A / bp5221a / bp5222a pin 9 sink current voltage difference between pins 2 and 9 fig.19 aso measurement circuit fig.18 safety operation range 4.5a 10 2.2a 1 0.1 110100 pw=1ms pw=10ms tc=25 c single pulse voltage between pin2 and pin9 (v) output current into pin9 (a) output current : i o (a) output current : i o (ma) ambient temperature : ta( c) 7/7 2010.03 - rev. b www.rohm.com ? 2010 rohm co., ltd. all rights reserved.
r1010 a www.rohm.com ? 2010 rohm co., ltd. all rights reserved. notice rohm customer support system http://www.rohm.com/contact/ thank you for your accessing to rohm product informations. more detail product informations and catalogs are available, please contact us. notes no copying or reproduction of this document, in part or in whole, is permitted without the consent of rohm co.,ltd. the content specified herein is subject to change for improvement without notice. the content specified herein is for the purpose of introducing rohm's products (hereinafter "products"). if you wish to use any such product, please be sure to refer to the specifications, which can be obtained from rohm upon request. examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the products. the peripheral conditions must be taken into account when designing circuits for mass production. great care was taken in ensuring the accuracy of the information specified in this document. however, should you incur any damage arising from any inaccuracy or misprint of such information, rohm shall bear no responsibility for such damage. the technical information specified herein is intended only to show the typical functions of and examples of application circuits for the products. rohm does not grant you, explicitly or implicitly, any license to use or exercise intellectual property or other rights held by rohm and other parties. rohm shall bear no responsibility whatsoever for any dispute arising from the use of such technical information. the products specified in this document are intended to be used with general-use electronic equipment or devices (such as audio visual equipment, office-automation equipment, commu- nication devices, electronic appliances and amusement devices). the products specified in this document are not designed to be radiation tolerant. while rohm always makes efforts to enhance the quality and reliability of its products, a product may fail or malfunction for a variety of reasons. please be sure to implement in your equipment using the products safety measures to guard against the possibility of physical injury, fire or any other damage caused in the event of the failure of any product, such as derating, redunda ncy, fire control and fail-safe designs. rohm shall bear no responsibility whatsoever for your use of any product outside of the prescribed scope or not in accordance with the instruction manual. the products are not designed or manufactured to be used with any equipment, device or system which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injury (such as a medical instrument, transportation equipment, aerospac e machinery, nuclear-reactor controller, fuel- controller or other safety device). rohm shall bear no responsibility in any way for use of any of the products for the above special purposes. if a product is intended to be used for any such special purpose, please contact a rohm sales representative before purchasing. if you intend to export or ship overseas any product or technology specified herein that may be controlled under the foreign exchange and the foreign trade law, you will be required to obtain a license or permit under the law.
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