1 standard ics el driver for portable sets BA3899F the BA3899F is an ic developed for el drive applications. it uses a more compact interface than transformer sys- tems, and is ideal for use in thin sets. applications pagers, electronic notebooks and other portable devices block diagram 8 7 6 1 2 3 5 stby 4 gnd n.c. c1 c2 sw1 sw2 v cc stby osc2 osc1 r sw2 features 1) drive oscillation frequency can be set using external capacitance. 2) equipped with standby control pin. absolute maximum ratings (ta = 25?) parameter power supply voltage power dissipation operating temperature storage temperature v cc pd topr tstg 8.0 450 * ?10 ~ + 60 ?55 ~ + 125 v symbol limits unit mw c c maximum applied voltage v st 8.0 v * reduced by 4.5mw for each increase in ta of 1 c over 25 c. recommended operating conditions (ta = 25?) parameter v cc 1.0 5.0 7.0 v symbol min. typ. max. unit power supply voltage
2 standard ics BA3899F pin descriptions v cc gnd c1 1k v cc gnd c2 200 w v cc gnd sw2 50k 500 w x20 x1 gnd stby 1k 200k 50k v cc gnd sw1 x5 x1 pin no. osc1 oscillator circuit; external capacitor pin osc2 oscillator circuit; external capacitor pin standby control pin (high state: standby cancelled) sw2 switching output pin sw1 switching output pin s when applying resistance, etc. to the stby pin, be careful not to exceed the threshold values. 2 n.c. ? cc input pin 6i v cc 3 i / o c1 4 i / o c2 5i0 stby 7o sw2 8o sw1 1 i gnd pin gnd pin name i / o pin voltage internal equivalent circuit function
3 standard ics BA3899F electrical characteristics (unless otherwise noted, ta = 25?, v cc = 5.0v, c1 = 0.033 m f, c2 = 1500pf) parameter symbol min. typ. supply current i cc ma when used as stand-alone unit 3.0 4.6 6.2 c1 pin oscillation frequency f sw1 hz 75 95 120 c2 pin oscillation frequency f sw2 khz 17 23 29 source current sw1 sw2 standby pin control voltage condition i sw1so m av c1 = 1.0v, v c2 = 0.05v, v sw1 = 0v 100 140 180 sink current i sw1si m av c1 = 0.05v, v c2 = 0.05v, v sw1 = 1.0v ?40 source current i sw2so ma v c1 = 0.05v, v c2 = 0.05v, v sw2 = 0v 3.2 4.4 6.1 pull-down resistance r sw2 w vst = 0.35v, v sw2 = 0.3v 400 500 600 operating v ston v 1.0 non-operating v stoff v 0.3 quiescent current in standby state i q (st) m a 0 2.0 max. unit conditions measurement circuit 2 i sw1 v sw1 f sw1 v cc counter v c1 0.033 f i q v stby 8 v c2 1500pf 1% 1% 1 i sw2 v sw2 f sw2 counter 7 3 4 stby osc2 osc1 r sw2 fig.1 a a a 6 5
4 standard ics BA3899F application example 5 6 7 stby 8 osc2 osc1 fig. 2 r sw2 el 16000pf r1 2k d1 q2 q1 l1 100k v cc = 5v rohm: 1ss376 rohm: 2sc4061kp sw1 sw2 stby r x 300k v cc sanyo: 2sc3645t 1.5mh (toko: d73lc) * gnd n.c. c1 c1 8200pf 10% 2.2 m f c2 1500pf 10% c2 1234 + * because of the characteristics of the el element, continuous application of particularly high dc power supply voltage can short en the lifetime of the element. to avoid this, we recommend inserting a switch in the power supply line.
5 standard ics BA3899F 2 5 stby gnd n.c. c1 c2 sw1 r1 4.7k rohm: 1ss376 d1 el 5000pf sw2 v cc v cc = 1.5v stby osc2 osc1 r sw2 q1 q2 l1 1mh rohm: 2sc4061kp sanyo: 2sc3143k5 ( toko: 43fs ) or ( tdk: nl453232 ) c2 1500pf 10% c1 0.033 f 10% 4 1 3 6 8 7 v stby = 1.5v hi: act fig. 3 2.2 m f +
6 standard ics BA3899F operation notes (1) el drive output as shown in figure 4, the el drive output consists of charging (rise in voltage caused by switching) and dis- charging waveforms. the switching frequency is deter- mined by f sw2 and the charging and discharging timing by f sw1 . (4) q1, q2, and d1 the v o ( max. ) shown in figure 4 is applied to the output v o , so if using any transistor other than that recom- mended, caution is required concerning the pressure withstand value. also, q2 must have characteristics which allow it to keep pace with the switching speed of f sw2 . t 1 t sw1 (f sw1 ) v o (max.) t 2 charge discharge fig.4 (2) setting f sw1 the oscillation frequency is determined by charging and discharging of the external capacitance of the c1 pin. the value for c1 should be set based on the fol- lowing equation. (5) r x (resistor for adjusting light volume) with a configuration like that shown in figure 5, the volume of light can be adjusted. however, r x should be set so that i x satisfies the following condition. c1 = = (3.14e ?6) ( + ) v c1 (v cc = 5v) 1 11 i 1 1 f sw1 i 2 1 f sw1 ix ( = ) < 40 m a vx ?0.2v rx if i x > 40 m a, lsi dispersion, temperature fluctuation, and other elements can cause oscillation of the c2 pin to stop. be sure the above condition is satisfied. the recommended setting range for f sw1 is 40hz to 800hz. however, the v o ( max. ) shown in figure 4 is determined by f sw1 , so caution is required concerning the pressure withstand values of q1, q2, and d1. (3) f sw2 f sw2 is the switching pressure rise frequency, and is determined by the external capacitance of the c2 pin. this value (1500pf) is determined by the inductance value and the q2 transistor capability. when changing this value, the drive capability of q2 must be taken into consideration in order to avoid the possibility of mal- function. 4 c2 1500pf vx rx ix fig.5
7 standard ics BA3899F electrical characteristic curves 0 012345678910 1 2 3 4 5 6 7 c1 = 0.033 m f c2 = 1500pf v st = 5v rx = 8 9 10 quiescent current: i cc (ma) 75 c ?25 c 25 c input voltage: v cc ( v) fig. 6 supply current (when used as stand-alone unit) vs. power supply voltage 10k 1k 100 023 15 4678 oscillation frequency: f sw (hz) c1 = 0.033 m f c2 = 1500pf rx = 75 c f sw1 f sw2 ?25 c 25 c 75 c ?25 c 25 c input voltage: v cc ( v) fig. 7 oscillation frequency of c1 and c2 pins vs. power supply voltage sw1 source current: i swiso ( m a) 0 012345678910 50 100 150 200 250 v c1 = 1.0v v sw1 = 0v 25 c ?25 c 75 c input voltage: v cc ( v) fig. 8 sw1 sink current vs. power supply voltage sw1 sink current: i sw1si (%) input voltage: v cc ( v) 0 012345678910 10 2.0 3.0 1.0 v c1 = 0v v sw1 = 1.0v v st = 5v 25 c ?25 c 75 c fig. 9 sw1 source current vs. power supply voltage 0 012345678910 1 2 3 4 5 6 7 v c1 = 1.0v v sw1 = 0v v st = 5v 8 9 10 sw2 source current: i sw2so (ma) input voltage: v cc ( v) 75 c ?25 c 25 c fig. 10 sw2 source current vs. power supply voltage 0 012345678910 100 200 300 400 500 600 700 v cc = 5v v sw2 = 0.2v v st = 0v 800 900 1000 sw2 pull-down resistance: r sw2 ( w ) input voltage: v cc ( v) 75 c ?25 c 25 c fig. 11 sw2 pull-down resistance vs. power supply voltage
8 standard ics BA3899F external dimensions (units: mm) sop8 0.4 0.1 1.27 0.15 0.3min. 0.15 0.1 0.11 6.2 0.3 4.4 0.2 5.0 0.2 85 4 1 1.5 0.1
appendix appendix1-rev1.0 the products listed in this document are designed to be used with ordinary electronic equipment or devices (such as audio visual equipment, office-automation equipment, communications devices, electrical appliances and electronic toys). should you intend to use these products with equipment or devices which require an extremely high level of reliability and the malfunction of with would directly endanger human life (such as medical instruments, transportation equipment, aerospace machinery, nuclear-reactor controllers, fuel controllers and other safety devices), please be sure to consult with our sales representative in advance. notes no technical content pages of this document may be reproduced in any form or transmitted by any means without prior permission of rohm co.,ltd. the contents described herein are subject to change without notice. the specifications for the product described in this document are for reference only. upon actual use, therefore, please request that specifications to be separately delivered. application circuit diagrams and circuit constants contained herein are shown as examples of standard use and operation. please pay careful attention to the peripheral conditions when designing circuits and deciding upon circuit constants in the set. any data, including, but not limited to application circuit diagrams information, described herein are intended only as illustrations of such devices and not as the specifications for such devices. rohm co.,ltd. disclaims any warranty that any use of such devices shall be free from infringement of any third party's intellectual property rights or other proprietary rights, and further, assumes no liability of whatsoever nature in the event of any such infringement, or arising from or connected with or related to the use of such devices. upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or otherwise dispose of the same, no express or implied right or license to practice or commercially exploit any intellectual property rights or other proprietary rights owned or controlled by rohm co., ltd. is granted to any such buyer. products listed in this document use silicon as a basic material. products listed in this document are no antiradiation design. about export control order in japan products described herein are the objects of controlled goods in annex 1 (item 16) of export trade control order in japan. in case of export from japan, please confirm if it applies to "objective" criteria or an "informed" (by miti clause) on the basis of "catch all controls for non-proliferation of weapons of mass destruction.
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