bp5319 / BP5319X power module dc/dc converter for lcds bp5319 / BP5319X the bp5319, BP5319X is a dc/dc converter designed for driving liquid crystal displays(lcds). if this module is used, a negative power supply for lcd can be made of the power supply easily 5v. ! applications a power supply for the lcd panels in copiers, facsimile, personal computers, word processors, musical instrument, and units. ! features 1) high accurate output voltage (-24v 0.75v). 2) high conversion efficiency (75%typ). 3) an output voltage can be changed by the external resistor. 4) built-in protect circuit. 5) built-in on/off switch. 6) compact and light. 7) available as an upright or l-shaped lead type. ! absolute maximum ratings (ta=25 c) parameter symbol limits unit input voltage v in 7v output current io 30 ma on/off control voltage v ctl 7v operating temperature topr -10 +60 c storage temperature tstg -30 +85 c
bp5319 / BP5319X power module ! electrical characteristics (unless otherwise noted, ta=25 c) parameter symbol min. typ. max. unit conditions input voltage v in 4.5 - 5.5 v output current i out --30ma out put voltage v out -24.75 -24.00 -23.25 v v in =5v, i out =25ma line regulation ? v1 --0.24v v in =4.5 5.5v, i out =25ma load regulation ? v2 --0.24v v in =5v, i out =0 25ma output voltage temperature coefficient ? vt --10- mv/ c v in =5v, i out =25ma *2 ripple noise voltage 1 --150mv p-p v in =5v, i out =25ma *1 conversion efficiency 70 75 - % v in =5v, i out =25ma on/off ctl voltage when off v ctl 2.0 - - v v in =5v -0.5v on/off ctl voltage when on v ctl - (alternatively, when open) v in =5v on/off ctl input current i ctl -100150 av in =4.5 5.5v, v ctl =5v *2 current consumption when off i off --0.5ma v in =4.5 5.5v, v ctl =5v *2 r1 resistance r1 50 - k ? v in =4.5 5.5v, v ctl =5v *2 r2 resistance r2 50 - k ? v in =4.5 5.5v, v ctl =5v *2 *1 measured with a bandwidth of 20mhz. *2 ta = -10~60 c ! pin descriptions pin no, pin name function 1 co output smoothing capacitor connection pin; connect a low-impedance capacitor with a recommended capacitance of 47 f between this pin and gnd. 2v out output pin 3v ref output voltage adjustment pin for contrast; output voltage is adjusted by connecting a resistor between pins 2 and 3 or pins 3 and 4. 4.7 gnd ground pin. pins 4 and 7 is internal connection. 8v ctl output on/off control pin; output starts when the pin is low level or open, and stops when the pin high level. 9v in input pin; connect a low-impedance capacitor with a recommended capacitance of 100 f between this pin and gnd.
bp5319 / BP5319X power module ! measurement circuit ! operation notes (1) place i/o external capacitors as near as possible to the connection pins. in particular, make sure to minimize the impedance between the input-side capacitor(c1)and pin 9 (reference value: a length less than 50mm for a copper foil of 1.0mm wide and 35 m thickness). (2) avoid frequent switching using the on/off ctl pin (four times per second at the maximum). ! application example (1) when increasing the output voltage (2) when reducing the output voltage (a minus side). (it is drawn to the zero electric potential wear).
bp5319 / BP5319X power module ! electrical characteristic curves fig.2 use possibility range fig.3 output voltage vs. feedback resistance (r1, r2) fig.4 output voltage vs. feedback resistance (r2<100k ? ) ! external dimensions (units: mm)
|
