D ts e t
aa h e
R c e t r lc r nc
o h se Ee to is
Ma u a t r dCo o e t
n fc u e
mp n n s
R c e tr b a d d c mp n ns ae
o h se rn e
o oet r
ma ua trd u ig ete dewaes
n fcue sn i r i/ fr
h
p rh s d f m te oiia s p l r
uc a e r
o h r n l u pi s
g
e
o R c e tr waes rce td f m
r o h se
fr e rae r
o
te oiia I. Al rce t n ae
h
r nl P
g
l e rai s r
o
d n wi tea p o a o teOC
o e t h p rv l f h
h
M.
P r aetse u igoiia fcoy
at r e td sn r n la tr
s
g
ts p o rmso R c e tr e eo e
e t rga
r o h se d v lp d
ts s lt n t g aa te p o u t
e t oui s o u rne
o
rd c
me t o e c e teOC d t s e t
es r x e d h
M aa h e.
Qu l yOv riw
ai
t
e ve
• IO- 0 1
S 90
•A 92 cr ct n
S 1 0 et ai
i
o
• Qu l e Ma ua trr Ls (
ai d
n fcues it QML MI- R -
) LP F
385
53
•C a sQ Mitr
ls
lay
i
•C a sVS a eL v l
ls
p c ee
• Qu l e S p l r Ls o D sr uos( L )
ai d u pi s it f it b tr QS D
e
i
•R c e trsacic l u pir oD A a d
o h se i
r ia s p l t L n
t
e
me t aln u t a dD A sa d r s
es lid sr n L tn ad .
y
R c e tr lcrnc , L i c mmi e t
o h se Ee t is L C s o
o
tdo
t
s p ligp o u t ta s t f c so r x e t-
u pyn rd cs h t ai y u tme e p ca
s
t n fr u lya daee u loto eoiial
i s o q ai n r q a t h s r n l
o
t
g
y
s p l db id sr ma ua trr.
u pi
e yn ut
y n fcues
T eoiia ma ua trr d ts e t c o a yn ti d c me t e e t tep r r n e
h r n l n fcue’ aa h e a c mp n ig hs o u n r cs h ef ma c
g
s
o
a ds e ic t n o teR c e tr n fcue v rino ti d vc . o h se Ee t n
n p c ai s f h o h se ma ua trd eso f hs e ie R c e tr lcr -
o
o
isg aa te tep r r n eo i s mio d co p o u t t teoiia OE s e ic -
c u rne s h ef ma c ft e c n u tr rd cs o h r n l M p c a
o
s
g
t n .T pc lv le aefr eee c p r o e o l. eti mii m o ma i m rt g
i s ‘y ia’ au s r o rfrn e up s s ny C r n nmu
o
a
r xmu ai s
n
ma b b s do p o u t h rceiain d sg , i lt n o s mpetsig
y e a e n rd c c aa tr t , e in smuai , r a l e t .
z o
o
n
© 2 1 R cetr l t n s LC Al i t R sre 0 1 2 1
0 3 ohs E cr i , L . lRg s eevd 7 1 0 3
e e oc
h
T l r m r, l s v iw wrcl . m
o e n oe p ae it w . e c o
a
e
s
o ec
LM4838 Stereo 2W Audio Power Amplifiers with DC Volume Control and Selectable Gain
November 2004
LM4838
Stereo 2W Audio Power Amplifiers
with DC Volume Control and Selectable Gain
General Description
The LM4838 is a monolithic integrated circuit that provides
DC volume control, and stereo bridged audio power amplifi-
ers capable of producing 2W into 4Ω (Note 1) with less than
1.0% THD or 2.2W into 3Ω (Note 2) with less than 1.0%
THD.
Boomer
®
audio integrated circuits were designed specifically
to provide high quality audio while requiring a minimum
amount of external components. The LM4838 incorporates a
DC volume control, stereo bridged audio power amplifiers
and a selectable gain or bass boost, making it optimally
suited for multimedia monitors, portable radios, desktop, and
portable computer applications.
The LM4838 features an externally controlled, low-power
consumption shutdown mode, and both a power amplifier
and headphone mute for maximum system flexibility and
performance.
Note 1:
When properly mounted to the circuit board, the LM4838LQ,
LM4838MTE, and LM4838GR will deliver 2W into 4Ω. The LM4838MT and
LM4838ITL will deliver 1.1W into 8Ω. See
Application Information
section
Exposed-DAP package PCB Mounting Considerations
for more informa-
tion.
Note 2:
An LM4838LQ and LM4838MTE that have been properly mounted
to the circuit board and forced-air cooled will deliver 2.2W into 3Ω.
Key Specifications
n
P
O
at 1% THD+N
n
into 3Ω (LQ & MTE)
n
into 4Ω (LQ, MTE, GR)
n
into 8Ω (MT, MTE, ITL, LQ, & GR)
n
Single-ended mode - THD+N at 85mW into
32Ω
n
Shutdown current
2.2W (typ)
2.0W (typ)
1.1W (typ)
1.0%(typ)
0.7µA (typ)
Features
n
n
n
n
n
n
DC Volume Control Interface
System Beep Detect
Stereo switchable bridged/single-ended power amplifiers
Selectable internal/external gain and bass boost
“Click and pop” suppression circuitry
Thermal shutdown protection circuitry
Applications
n
Portable and Desktop Computers
n
Multimedia Monitors
n
Portable Radios, PDAs, and Portable TVs
Block Diagram
20013301
FIGURE 1. LM4838 Block Diagram
Boomer
®
is a registered trademark of NationalSemiconductor Corporation.
© 2004 National Semiconductor Corporation
DS200133
www.national.com
LM4838
Connection Diagrams
LLP Package
20013335
Top View
Order Number LM4838LQ
See NS Package Number LQA028AA for Exposed-DAP LLP
TSSOP Package
20013302
Top View
Order Number LM4838MT
See NS Package Number MTC28 for TSSOP
Order Number LM4838MTE
See NS Package Number MXA28A for Exposed-DAP TSSOP
www.national.com
2
LM4838
Connection Diagrams
(Continued)
36 Bump micro SMD
20013388
Top View
Order Number LM4838ITL, LM4838ITLX
See NS Package Number TLA36AAA
micro SMD Marking
20013387
Top View
X - Date Code
T - Die Traceability
G - Boomer Family
A4 - LM4838ITL
36 Bump micro SMD Pinout Table
6
5
4
3
2
1
Pin
Designator
NC
GND
Bypass
HP Sense
GND
NC
A
Right Out -
Right Gain 2
NC
NC
Left Gain 2
Left Out -
B
V
DD
Right Gain 1
NC
NC
Left Gain 1
V
DD
C
Right Out +
Gain Select
DC Vol
Beep In
Left In
Left Out +
D
GND
Shutdown
Mute
Right Dock
Left Dock
GND
E
NC
Mode
V
DD
GND
Right In
NC
F
3
www.national.com
LM4838
Connection Diagrams
49 Bump micro Array
20013344
Top View
Order Number LM4838GR
See NS Package Number GRA49A
49 Bump micro Array Marking
20013343
Top View
NS - Standard National Logo
U - Wafer Fab Code
Z - Assembly Plant Code
XY - 2 Digit Datecode
TT - Dierun Traceability
L4838GR - LM4838GR
49 Bump LM4838GR Pinout Table
7
6
5
4
3
2
1
Pin
Designator
Right Out -
Right Out -
VDD
Right Out +
GND
Shutdown
Mode
A
Right Gain 1
Right Gain 2
VDD
Right Out +
GND
Gain Select
Mute
B
GND
GND
GND
GND
GND
VDD
DC Vol
C
Bypass
GND
GND
GND
GND
GND
GND
D
HP Sense
GND
GND
GND
GND
Right In
Right Dock
E
GND
Left Gain 2
Left Out -
Left Out +
GND
Left In
Beep In
F
Left Gain 1
Left Out -
VDD
VDD
Left Out +
GND
Left Dock
G
www.national.com
4
京公网安备 11010802033920号
EEWORLD
