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Epllaxlal Planar
PilP Sllicon Transistors
) NEHM
258737258821
Ultra'Low Noise Low-FrequencY
Amplilicalion \J
Low Base Fesistancefor use in MC Head
Ampliliers
Electrical CharacteristicCurves
D i m e n s i o n( m m )
s
^^^-^' JEOEC ro 92 2 5 8 8 2 1 - F 0 H MF T R
z)Drr,.EtAJ .SC_41
I losc
'm
i_1-
m
tl I
tl i
-Ttr i
z
tfr t
z
IU I llF 0.45
d
z
; l
6
6
E: Emilter
C: Collectol 3
B: Base
0 0.2 -0.4 -0.6 {.8 -1.0 0 -0.4 0.8 ,1.2 -1.6 -2.0
This ultra-lownoise transistoris suilable AbsoluteMaximum Ratings(T.- 25'C) AMBIENT
TEMPEFATUFE:
T. fC) TO
COLLECTOF EMITTERvOLTAG: (v)
vcr
SASE EMITTER
TO VOLTAGE, (V)
Vr
lor use in fread amplifiersfor MC car- ilem
Frg.
't
Maximum power dissipataon
vs. Fig. 3 Collrctor current vs. colledoFto-
Fig.2 Coll*tor drrent vs. bGe{oemitter
tndges. ambrenltemperature voltage emittervoltage
Collectorto-eminer volBge
Emitterto-base voltage
res
Featu Collector current
1. Ultra-low orse:n CollectordlssiPation z
NF-2 sdB (typ) Junction temPerature
-
( a t f = 1 0 H z ,R s - 1 0 o , t 6
Vc:=-6V, 1c=-3mA) .a
N F = 1. 0 d B ( t y p ) \t: z
o ,o
(at 1-1 0Hz, Rs=1 00O VcL--6v Electrical Characteristics (T"=25'C)
lc=-0.5- 2mA)
a o
2. Low base resistancers =2() f
z -0
Colleclor{o-emlter
3. Low voltagenoise:e"=0 55nV/lF7
O
o
3k
( a t1 O H z , 1 O m A ) -0.5 1 ,2 5 10 -20 50 r00 -200
4. Cornplementary with 2SD786(reterto C O L L E C T O C U R R E N Tl:c ( m A )
R o< C O L L E C T O RC U B R E N T : l c ( F A )
P a g e 1 9 4 ) n d w h e nu s e di n c o m b l n a -
a Fig.4 DC curenl gain vs- @llectorcurrent Fig.5 Colleclor saturation voltage vs. colleclor
tion with that device, these lrasistors current
can comPrise an ultra high Pertor'
mance head amPlifier.
;
Applications
1. [,4ClMN4Head/cartridge ampliJier I z
= tr
2 . H e a d a m p l i f i e t so r l o w ' l m p e d a n c e
f
I
l n p u lc l r c u l l s
FLAT AMP (Gr=80d8)
V.r=-10V, lc=-1mA z
F
5 l
o
F
!
Devices are classifiedaccordlngto tnelr a o
F
hFErange as shown below t:
rtemlolRls
h,, | 12o 270 | 180 390 | 270 560
CoLLECTOR TO EASE VOLTAGE V(r (V)
E M I T T E R U R R E N Tl:E { m A }
C
Fig.6 Transilion lrequency 6. emittel Fig. 7 Oulput capacilance vs. collectotrlo-
currenl base voilage
f{
NTTHM
\ I
;
z
i
TRtOUENCY I (Hr)
F Fig 15 Noise curenl vs. lrequenry
l
4
F
L 258737 and 25D7B6Noise To achieve a low value of e":
= E M I T T E R O B A S E O L T A G E V E B( V l
T V COLLECTOF UFBENT lc (dAl
C
Characteristics 1 . L o w e rr . ( . e . ,m a k e l r j l a r g e )
2SD786
l'.10Hz,
F i 9 .I I n p ! t c a p a c i t a n c v s e m t t e r t o _ b a s e
e Fig t h parameters vs. collector current
2. Lower rrr' 10f) 2.5dB 2.5d4
voLrage N o i s ei s a n i l n p o r t a nc o n sd e r a t i o n h e n
l w With the aim ol loweringrnr,spec a difiu- l,.3mA
arnpiifying s gnals lrom such lolv, sron lechnrques and a new passrvalron 1 0 0 o 1.0d8 t=10H2.
resrslance 1.0d8
sourcesas MC carlndgesThrs technique were used in developingthe l.- lmA
is becauscthe N.1C carlildgermpeoance rs
: 2SD786 and 258737, resultingin values
i n l h e r a n g e2 " 1 0 0 O . of r,$ of approximalely 4O and 2o It rs possrbleto configure an ullra hrgh
s W h e n l h e a r n p i i t l eo u t p u tn o i s e r s c o n
r respectively. p e r t o r m a n c eh e a d a m p l i f i e ru s i n g t h e
v e r l e d1 oa n c q u i v a l e nn o i s ea t l h e i n p u l
t
: w e d e rv e l h e l o l o w i n gr e l a l l o n s h i p .
T h e s u b s e q u e n l l a c h r e v e d a l u e so f e " 2 S 8 7 3 7 a n d 2 S D 7 8 6 t r a n s l s l o r sO n e
y v .
I 2 are example of the periormancethal can be
; I \ I n.r,"*
v;ric"+4x1t,
2SD786:Approx.o.ssnvi /aHz (al 10H2, a c h i e v e dr s a n i n p u t - r e f e r r en o i s ev o l t d
1O m A ) a g e o l - 1 5 9 d B a n d a n S / N r a t i oo l 8 1d B
i tr
2 S 8 7 3 7 :A p p r o x 0 . 5 5 n V / V H z ( a t 1 0 H 2 , (at 0.125mV inpul).an easily achievabte
T AD-r.irnr r'',,0.,1r1,'n
< lrl,_ i-- s aLr'rlta r
10rnA) level ol perlormance.
When we lower the value of r., however,
6 h e c u r r e n tn o i s el e r m i " b e c o m e ss u c h
thal il caf no longer be lgnored This i"
coLLacToc!RFEfrr . .!
F C O L L E C I O B F n E NlT " i
CU ' term is expressed by lhe lollowing
and
Fig 12 Noiseligure vs sourceresistance
relatronshrp.
and
Fig. l0 Noiseligure vs soorceresislance Fig. 11 Noisefigurevs. source16istanceand
colleclorcurent (l) collectorcurrent (ll) colleclorcurrent (lll)
i"=\2q l
jt
When lB increases, causes an tncrease
li In i",so thal lo reduce1B musl increase
we
Thrs means that, Ior low values of Ra,e" h ' $ d r n 6 1 g 2 5 1 q gI T a { e s l h e b i " e h'
I
5to (lhe voltagcnorse)rs the governng factor. w d t h
s r a l l c r c a J s i l g a ^ i n c ' e a s en ' . .
I
T h r s t e r n e ^ r s d e f i n e db y l h e l o l l o w i n g Thus,a way musl be Jound increaseh! r: lo
=a = expressron. without caus ng the reverse result ol
^n_ , q' ^; ;| ; " T,, r , * reducinglhe base widlh.The ROHl.4 solu
9
c \ tr',h /^l
tionlo this problemwas a specialdiflusion
E
techinique The rcsult ol lowenng lhe
'. f ' rr, ' ', ,:r.r, . Ail rL-:51.... ol lrirr Llfillrr values ol e' and i" in the 2St)786 and
258737 was the achievernenl ullra low ol
u 02 norse characlerlstlcs herelolore
KT impossible
a
9
aa C O L L E C I O R C U B R E N T I C( M A ) ! FREOUNCY | (Hzl
Fig 13 Noise vollageandcurrenlvs.collector
? Fig 14 Noise voltage vs. lrequency
t