unisonic technologies co.,ltd. tea2025 linear integrated circuit www.unisonic.com.tw 1 copyright ? 2005 unisonic technologies co.,ltd. qw-r107-033.b stereo audio amplifier ? description the utc tea2025 is a monolithic integrated audio amplifier in a 16-pin plastic dual in line package. it is designed for portable cassette players and radios. ? features *working voltage down to 3v *few external components *high channel isolation *voltage gain up to 45db(adjustable with external resistor) *soft clipping *internal thermal protection dip-16 *pb-free plating product number: tea2025l ? ordering information order number normal lead free plating package packing TEA2025-D16-T tea2025l-d16-t dip-16 tube ? pin configuration 1 2 3 4 16 15 14 13 12 11 10 9 8 7 6 5 +vs out.1 boot.1 gnd gnd feedback in.1 (+) gnd (sub) svr in.2 (+) feedback gnd gnd boot.2 out.2 bridge
tea2025 linear integrated circuit unisonic technologies co., ltd 2 www.unisonic.com.tw qw-r107-033.b ? block diagram 7 8 9 10 11 12 13 14 15 16 1 2 3 5 6 4 thermal protection start circuit decoupling 10k 10k 50 50 50 5k
tea2025 linear integrated circuit unisonic technologies co., ltd 3 www.unisonic.com.tw qw-r107-033.b ? absolute maximum ratings (ta = 25 ) parameter symbol ratings unit supply voltage v ss 15 v peak output current i o (peak) 1.5 a junction temperature t j 150 c operating temperature t opr -20 ~ +85 storage temperature t stg -40 ~ +150 note 1. absolute maximum ratings are those values beyond which the device could be permanently damaged. absolute maximum ratings are stress ratings only an d functional device operat ion is not implied. 2. the device is guaranteed to meet performance specification within 0 ~70 operating temperature range and assured by design from ?20 ~85 . ? electrical characteristics (ta=25 , v cc =9v, stereo, unless ot herwise specified.) parameter symbol test conditions min typ max unit supply voltage v ss 3 12 v quiescent current i q 40 50 ma quiescent output voltage v out 4.5 v stereo 43 45 47 db voltage gain g v bridge 49 51 53 voltage gain difference g v +-1 db input impedance r in 30 k r l =4 1.7 2.3 r l =8 f=1khz,thd=10%, v cc =9v stereo per channel 1.3 r l =4 0.7 1 r l =8 v cc =6v 0.6 r l =4 v cc =3v 0.1 r l =8 bridge, v cc =9v 4.7 output power r l =4 p out v cc =6v 2.8 w stereo v cc =9v, r l =4 , f=1khz,p out =250mw 0.3 1.5 total harmonic distortion bridge thd 0.5 % supply voltage rejection svr r g =0,av=45db,v ripple =150mv f ripple =100hz 40 46 db r g =0 1.5 3 input noise voltage r g =10k vn a v =200, bandwidth:20hz ~ 20khz 3 6 v cross-talk c.t. r g =10k , f=1khz,r l =4 , p out =1w 40 55 db ? thermal characteristics parameter symbol ratings unit thermal resistance junction to ambient ja 60 thermal resistance junction to case jc 15 /w
tea2025 linear integrated circuit unisonic technologies co., ltd 4 www.unisonic.com.tw qw-r107-033.b ? application information input capacitor input capacitor is pnp type allowing source to be referenc ed to ground. in this way no input coupling capacitor is required. however, a series capacitor (0.22 uf)to the input side can be useful in case of noise due to variable resistor contact. bootstrap the bootstrap connection allows to in crease the output swing. the suggest ed value for the bootstrap capacitors (100uf) avoids a reduction of the output signal also at low frequencies and low supply voltages. voltage gain adjust stereo mode figure 1 the voltage gain is determined by on-chip resistors r1 an d r2 together with the external rfc1 series connected between pin 6 (11) and ground. the frequency response is given approximated by: v out v in = r 1 r f + r 2 + 1 jwc1 with r f =0, c 1 =100 f, the gain results 46 db with pole at f=32 hz. the purpose of rf is to reduce the gain. it is recommended to not reduce it under 36 db. c1 r f 6 (11) r 2 r 1 2 (15) figure 1 bridge mode (figure 2) the bridge configuration is realized very easily thanks to an internal voltage divider which provides (at pin 1) the ch 1 output signal after reduction. it is enough to connect pin 6 (inverting input of ch 2) with a capacitor to pin 1 and to connect to ground the pin 7. the total gain of the bridge is given by: and with the suggested values (c1 = c2 = 100 uf, r f = 0) means: gv = 52 db with first pole at f = 32 hz
tea2025 linear integrated circuit unisonic technologies co., ltd 5 www.unisonic.com.tw qw-r107-033.b out in r1 r1 r2 r2 r4 r3 out figure 2 output capacitors the low cut off frequency due to output capacitor depending on the load is given by: with c out 470uf and r l = 4 ohm it means f l = 80hz. pop noise (figure 3) most amplifiers similar to utc tea2025 need external resistors between dc outputs and ground in order to optimize the pop on/off performance and crossover distortion. out 800 figure 3 the utc tea2025 solution allows to save components because of such resistors (800 ohm) are included into the chip. stability a good layout is recommended in order to avoid oscillati ons. generally the designer mu st pay attention on the following points: - short wires of components and short connections. - no ground loops. - bypass of supply voltage with capacitors as nearest as possi ble to the supply i. c. pin. the low value (poliester) capacitors must have good temperat ure and frequency characteristics. - no sockets. the heatsink can have a smaller factor of safety compared with that of a conventional circuit. there is no device damage in the case of excessive junction te mperature: all that happens is that p o (and therefore p tot ) and id are reduced.
tea2025 linear integrated circuit unisonic technologies co., ltd 6 www.unisonic.com.tw qw-r107-033.b ? typical application circuit 16 10 11 7 6 1 8 4,5,9,12,13 14 15 3 2 100 f 0.15 f 100 f 0.15 f rl 100 f 100 f 100 f 0.22 f 100 f vin vcc 16 10 11 7 6 8 4,5,9,12,13 14 15 3 2 100 f 0.15 f 470 f 100 f 100 f 0.22 f 100 f vin 1 vcc 100 f 0.22 f vin 2 470 f 0.15 f 100 f out1 out2 rl rl fig. 4 bridge application fig.5 stereo application ? schematic diagram
tea2025 linear integrated circuit unisonic technologies co., ltd 7 www.unisonic.com.tw qw-r107-033.b ? typical characteristics utc assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all utc products described or contained herein. utc products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. the information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice.
|
