AN9 Datasheet, PDF (5/7 Pages) Copal Electronics – Digital Potentiometers

(5
*647(9(;69*09*<0;:
7KH SHUIRUPDQFH RI WKH WZR FRPSDUDWRU FLUFXLWV LQ )LJXUH  LV LQGHSHQGHQW RI WKH HQG WR HQG UHVLVWDQFH RI WKH
SRWHQWLRPHHU,QWKHOHYHOGHWHFWRUFLUFXLWRI)LJXUHDWKHVLJQDOVRXUFH9₆DQGWKHUHIHUHQFHYROWDJH9₅₍₎ DUHVXPPHG
WKURXJKWKHSRWHQWLRPHWHU7KHKLJKORZVWDWXVRIWKHGHWHFWRU·VRXWSXWLVGHWHUPLQHGE\WKHLQSXWYROWDJH9_,1)RU
WKHFLUFXLW
9_,1   S9₆  S9₅₍₎ IRUbSb
7KHFLUFXLWLQ)LJXUHELVDVLQJOHVXSSO\YHUVLRQRIDSURJUDPPDEOH6FKPLWW7ULJJHURUDFRPSDUDWRUZLWKK\VWHULVLV
7KHORZHU9_// DQGXSSHU9_8/ OLPLWVRIWKHK\VWHULVLVFKDUDFWHULVWLFDUHDIXQFWLRQRIWKHUHODWLYHVHWWLQJRIWKH
SRWHQWLRPHWHU·VZLSHUDQGDUHJLYHQDV
9_// S9
DQG
9_8/  9S9
ZKHUHSLVDGLPHQVLRQOHVVQXPEHUIURPWR7KHFKDUDFWHULVWLF·VORZHUOLPLWFDQEHSURJUDPPHGIURP9WR9
DQGWKHXSSHUOLPLWFDQEHSURJUDPPHGIURP9WR97KHWZROLPLWVDUHFRPSOHPHQWDU\DQGUHODWLYHO\VWDEOHZLWK
WHPSHUDWXUH
96
9,1
b ^S5327
b ^S5327
95()
$
9287
9
96
$
9287
9
S5327 S5327
H3L]LS+L[LJ[VY
-PN\YL*VTWHYH[VY*PYJ\P[Z
I:JOTP[[;YPNNLY
:8<(9,>(=,6:*033(;69
7KHRVFLOODWRULQ)LJXUHKDVWZRNH\SDUDPHWHUVIUHTXHQF\RIRVFLOODWLRQDQGGXW\F\FOH)RUWKHEDVLFFLUFXLW
ZKHUH5_ 5_ 
I_26&


5₃₂₇  S&
IRUbSb
DQG
'&



S
IRUbSb
7KHGXW\F\FOHLVDXWRPDWLFDOO\LQGHSHQGHQWRIWKHSRW·VHQGWRHQGUHVLVWDQFHDQGLVUHODWLYHO\WHPSHUDWXUHVWDEOH

'RFXPHQW1R5HY$