voltage regulator with external power transistor rn5rg series 1 outline the rn5rg series are cmos-based voltage regulator ics with an external power transistor with high output voltage accuracy and lowest supply current. each of these voltage regulator ics consists of a voltage reference unit, an error amplifier and resistors. these ics are suitable for constructing regulators with ultra-low dropout voltage and an output current in the range of several tens ma to several hundreds ma. furthermore, these ics have a chip enable function, so that the supply current on standby can be minimized. since the package for these ics is sot-23-5 (mini-mold) package, high density mounting of the ics on boards is possible. ?ultra-low supply current .............................. typ. 50? ?standby mode ..................................................... typ. 0.2? ?ultra-low dropout voltage ............................. typ. 0.1v (i out =100ma : dependent on external tr.) ?low temperature-drift coefficient of output voltage ................... typ. ?00 ppm/?c ?excellent line regulation ................................ typ. 0.1%/v ?output voltage ................................................. stepwise setting with a step of 0.1v in the range of 2.0v to 6.0v is possible (refer to selection guide). ?high accuracy output voltage ........................ ?.5% ?small package .................................................. sot-23-5(mini-mold) features applications power source for battery-powered equipment. power source for cameras, vcrs, camcorders, hand-held audio instruments, and hand-held communication equipment. power source for domestic appliances. block diagram 2 5 4 3 1 vr e f v out gnd v dd + ext ce no. ea-020-0204
rn5rgxxxx xx part number abc d rn5rg 2 selection guide the output voltage, the version, the packing type, and the taping type for the ics can be selected at the user's request. the selection can be made by designating the part number as shown below : for example, the product with output voltage 5.0v, version a, and taping type tr is designated by part number rn5rg50aa-tr. code contents setting output voltage (v out ): a stepwise setting with a step of 0.1v in the range of 2.0v to 6.0v is possible. ba designation of packing type: c a: taping c: antistatic bag for samples designation of taping type: d ex. tr, tl (refer to taping specifications) tr is prescribed as a standard. } }
absolute maximum ratings are threshold limit values that must not be exceeded even for an instant under any conditions. moreover, such values for any two items must not be reached simultaneously. operation above these absolute maximum ratings may cause degradation or permanent damage to the device. these are stress ratings only and do not necessarily imply functional operation below these limits. rn5rg 3 pin configuration pin description pin no. symbol 1 gnd 2v dd 3v out 4 ext 5ce ? sot-23-5 12 3 54 (mark side) description ground pin input pin output pin external transistor drive pin (nch open drain output) chip enable pin absolute maximum ratings symbol item v in input voltage v ce input voltage (ce pin) v ext ext output voltage i ext ext output current p d power dissipation topt operating temperature range tstg storage temperature range tsolder lead temperature (soldering) rating unit +12 v 0.3 to v in +0.3 v +12 v 50 ma 150 mw 40 to +85 ? c 55 to +125 ? c 260 ? c,10s absolute maximum ratings
rn5rg 4 electrical characteristics symbol item v out output voltage i out output current i ext ext current ? v out load regulation ? i out v dif dropout voltage i ss supply current istandby supply current (standby) i ext leak ext leakage current ? v out ? v in line regulation v in input voltage v ext ext output voltage ? v out output voltage ? topt temperature coefficient v ceh ce input voltage h v cel ce input voltage l i ceh ce input current h i cel ce input current l conditions min. typ. max. unit note v in =8.0v v out v out v i out =50ma 0.975 1.025 v in v out =1.0v 1000 ma note v in =4.0v, v ext =2.0v 10 ma v in v out =1.0v 1ma i out 100ma 60 60 mv i out =100ma 100 200 mv v in v out =1.0v i out =0ma (at no load) 50 80 a v in =8v 0.01 0.20 1.00 a 0.5 a i out =50ma 0.0 0.1 0.3 %/v v out +0.5v v in 8v 8v 8v i out =10ma 40 ? c topt 85 ? c 100 ppm/ ? c 1.5 v 0.25 v 0.0 0.1 a 5.0 3.0 0.1 a topt=25 ? c (note) the output current depends upon the performance of external pnp transistor. use external pnp transistor of a low satu ration type, with an h fe of 100 or more. * ) with respect to test circuits, refer to the typical application.
rn5rg 5 operation v out gnd gnd vref v dd external pnp transistor ext out in ra rb ce + 2 4 3 error amplifier 5 1 in these ics, the output voltage v out is detected by feed-back registers ra, rb, and the detected the output voltage is compared with a reference voltage by error amplifier, so that the base current of an external pnp transistor is adjusted and the output voltage v out is reg- ulated. selection guide for external components v out c l v in external pnp transistor ext out r1 r2 3 4 select an external pnp transistor from the view- points of output current, input voltage and power dis- sipation. generally external pnp transistor with low v ce ( sat ) and high h fe is suitable. 1.external pnp transistor ext pin of these ics is protected by a current limit circuit from the destruction caused by excess current. however, since this current limit circuit is provided for the purpose of protecting the ic, use a resistor r2 for the protection of the external transistor, although this ic can be operated without such a resistor. it is required that the resistance of the resistor r2 be determined with the input voltage, output voltage,output current, tempera- ture, and the h fe value taken into consideration and the dispersion of these values. before making such a deter- mination, check the characteristics by calculating the respective values by using the following formula : v in [min.] 1.2(v) 0.7(v) > i out [max.] r2 r1 h fe 2.base resistor r2 in these ics, phase compensation is made for securing stable operation even when the load current is varied. for this purpose, be sure to use a capacitor c l (tantalum type) with a capacitance of 10f or more and a resistor r1 with a resistance of about 10k ? between the base and the emitter.there may be the case the loop oscillation takes place when a tantalum capacitor c l with a large esr is used, so select the c l carefully including the fre- quency characteristics. 3.phase compensation
rn5rg 6 test circuits test circuit 1 : typical characteristics 1) to 4) test circuit 2 : typical characteristics 5) to 7) test circuit 3 : typical characteristics 8) to 10) test circuit 4 : typical characteristics 11) i out v out gnd v dd ext rn5rg series 2sa1213 pnp out in ce 2 4 5 1 3 10k ? 10 f 10 f v out gnd v dd ext rn5rg series 2sa1213 pnp oscilloscope in ce c l 2 4 5 1 3 10k ? p.g. i ss gnd v out v dd ext rn5rg series 2sa1213 pnp out in ce (2) (1) 10k ? 2 4 5 1 10 f 3 1f 10ma 300ma v out gnd v dd ext rn5rg series 2sa1213 pnp oscilloscope in ce 2 4 5 1 3 10k ?
rn5rg 7 typical characteristics 1) output voltage vs. input voltage rn5rg50a rn5rg30a rn5rg50a 2) output voltage vs.output current rn5rg50a rn5rg30a 3) dropout voltage vs. output curret rn5rg30a 3.0 4.0 5.0 6.0 7.0 8.0 3.0 3.5 4.0 4.5 5.0 input voltage v in (v) output voltage v out (v) topt=25 ? c i out =0ma i out =100ma i out =500ma output current i out (ma) dropout voltage v dif (v) 0 200 400 600 800 1000 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 topt=85 ? c 40 ? c 25 ? c 2345678 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 input voltage v in (v) output voltage v out (v) topt=25 ? c i out =0ma i out =100ma i out =500ma 0 100 200 300 400 500 output current i out (ma) 2.960 2.962 2.964 2.966 2.968 2.970 2.972 2.974 output voltage v out (v) topt=25 ? c v in =4.0v 3.1v output current i out (ma) dropout voltage v dif (v) 0 200 400 600 800 1000 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 topt=85 ? c 40 ? c 25 ? c 0 100 200 300 400 500 output current i out (ma) 4.942 4.944 4.946 4.948 4.950 4.952 4.954 4.956 4.958 4.960 4.962 output voltage v out (v) topt=25 ? c v in =6.0v 5.1v
rn5rg 8 4) output voltage vs.temperature 5) supply current vs. input voltage 6) supply current vs. temperature v in =4v,i out =10ma 0 2.95 2.97 2.99 3.01 3.03 3.05 20 40 60 80 100 -20 -40 -60 temperature topt ( ? c) output voltage vout (v) rn5rg30a v in =6v,i out =10ma 0 5 5.02 5.04 5.06 5.08 5.1 20 40 60 80 100 -20 -40 -60 temperature topt ( ? c) output voltage vout (v) rn5rg50a input voltage v in (v) supply current iss( a) i out =0ma 34 67 5 0 10 20 30 40 50 60 70 80 90 100 8 2 rn5rg30a topt=-40 ? c 25 ? c 85 ? c v in =4v,i out =0ma supply current iss( a) 0 60 50 40 30 20 10 rn5rg30a 0 20 40 60 80 100 -20 -40 -60 temperature topt ( ? c) supply current iss( a) v in =6v,i out =0ma 0 60 50 40 30 20 10 rn5rg50a 0 20 40 60 80 100 -20 -40 -60 temperature topt ( ? c) input voltage v in (v) supply current iss( a) i out =0ma 467 5 0 10 20 30 40 50 60 70 80 90 100 8 rn5rg50a topt=-40 ? c 25 ? c 85 ? c
rn5rg 9 7) standby current vs. input voltage 9) line transient response (1) 8) ripple rejection 10) line transient response (2) 11) load transient response standby current istandby( a) 0 0.15 0.4 0.35 0.3 0.25 0.2 0.45 0.1 0.05 rn5rg30a 12 8 7 6 5 4 3 temperature topt ( ? c) topt=85 ? c 40 ? c 25 ? c standby current istandby( a) 0 0.15 0.4 0.35 0.3 0.25 0.2 0.45 0.1 0.05 rn5rg30a 12 8 7 6 5 4 3 temperature topt ( ? c) topt=85 ? c 40 ? c 25 ? c input voltage v in (v) 20 40 60 80 100 120 140 0 4 5 6 7 8 i out =10ma topt=25 ? c output voltage deviation v out (v) 20 10 0 10 20 30 40 50 time t(s) c l =1f input voltage output voltage rn5rg50a output current i out (ma) 4 8 12 16 20 24 140 0 v in =6.0v topt=25 ? c output voltage deviation v out (mv) 100 300 200 100 0 100 200 300 400 500 0 100 200 300 400 500 time t(ms) c l =1f output current output voltage rn5rg50a 10 100 1k 10k 100k frequency f(hz) 0 10 20 30 40 50 60 ripple rejection rr(db) topt=25 ? c c l =10 f i out =200ma v in =6vdc+0.5(p-p) rn5rg50a input voltage v in (v) 20 40 60 80 100 120 140 0 4 5 6 7 8 i out =100ma topt=25 ? c output voltage deviation v out (mv) 20 10 0 10 20 30 40 50 time t(s) c l =1f input voltage output voltage rn5rg50a
rn5rg 10 typical application pnp tr out in ext ce gnd cap. + cap. + v out v dd rn5rg series parts transistor : 2sa1213 resistor : 10k ? capacitor : 10f(tantalum type)
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