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TRANSCRIPT
Three Decades of Quality Through Innovation
Linear Integrated Systems • 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490-9160 • Fax: 510 353-0261 • Email: [email protected]
By Dimitri Danyuk
Linear Integrated Systems
Headphone Amplifier Evaluation Board
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Linear Integrated Systems headphone amplifier evaluation board
Dimitri Danyuk
Contents
1 Introduction 1 1.1 Features 1 1.2 Description 1 1.3 Specifications 2 2 Operation 2 2.1 Precautions 2 2.2 Quick start list for evaluation board 2 3 Circuit description 3 4 Measurements 4 5 References 8 6 Documents 9 6.1 Linear Integrated Systems headphone amplifier evaluation board schematic diagram 6.2 Linear Integrated Systems headphone amplifier evaluation board parts list 6.3 Linear Integrated Systems headphone amplifier evaluation board PCB Layers
1 Introduction
1.1 Features
Linear Integrated Systems headphone amplifier evaluation board includes the following features:
Stereo, single‐ended input and single‐ended output 400 mW output power into 100Ω Wide frequency response (10Hz‐200kHz; ‐1dB) Voltage gain 5 (14dB) Low distortion (THD+N is less than 1% at 10Hz‐20kHz at 5Vrms into 100Ω and less than 0.1% from 10 Hz to 20 kHz at 1Vrms into 100Ω load) Short‐circuit protection Pop reduction (slow start) circuit Defeatable cross‐feed circuit Volume control Overvoltage and reverse polarity power protection Audio input and output connections: left and right RCA phono jack inputs, ¼” stereo phone jack output External 9V–16V supply input External power supply connector: power jack, inside diameter 2.1mm, outside diameter 5.5mm
1.2 Description
Page 2 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Linear Integrated Systems headphone amplifier evaluation board is a complete, low‐power stereo audio amplifier for high‐fidelity line‐level output and headphone applications. It consists of Linear Integrated Systems JFETs along with a number of other parts mounted on a circuit board (Fig 1).
1.3 Specifications
Supply voltage range 9V to 16V Supply current 380mA typ, 850mA max (12V) Continuous output power, 100Ω load 400 mW/ch, THD+N < 1% Audio input voltage 1.3 Vrms, max Minimum load impedance 100 Ω Maximum output current 55 mA rms
2 Operation
2.1 Precautions
Power supply polarity and maximum voltage
Always ensure that the polarity and voltage of the external power connected to power jack J1 is correct. Overvoltage or reverse‐polarity power applied to J1 may damage onboard transient voltage suppression (TVS) diode, onboard DC‐DC converter and cause damage to the power source. Please note that onboard DC‐DC converter has overvoltage protection, amplifier is not powered, if the power source voltage is greater than 16V.
2.2 Quick start list for evaluation board
1) Select and connect a 9V–16V power source to a power jack J1
2) Ensure that signal source level is set to minimum
3) Connect the audio source to left and right RCA phono jacks J2 and J4
4) Connect the load (headphones) to headphone jack J3.
5) Verify correct voltage and input polarity according to the silkscreen placed near J1 and set the external power supply to ON. On‐board LEDs (D3,D8,D103,D108) light indicate the presence of power
6) Adjust the signal source level as needed with volume potentiometer (R139)
7) Enable cross‐feed circuit by pressing switch SW1
Page 3 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Fig 1 Linear Integrated Systems headphone amplifier evaluation board connections
3 Circuit description
The input stage is a complementary differential JFET stage, based on LSK489 and LSJ689 (U1 and U2). This topology is popular for audio amplifier design (Refs 1‐3). Each of these JFETs is working with 4mA drain current. Dual differential JFET input stage can handle fairly large input signals with low distortion. The input stage is loaded with complementary common gate stage, based on LSK170 and LSJ74 (Q12 and Q2). Complementary common gate stage operates at 5mA and provides single ended drive to the output stage. Output stage is a complementary source follower and consists of three LSK170 (Q3‐Q5) and three LSJ74 (Q8‐Q10). Output devices operate at 10mA each and have large copper pads for heat dissipation. Three JFET pairs in parallel allow driving loads up to 100Ω. Limiter diodes D4 and D7 prevent excessive source current in the output devices when the output of the amplifier is shorted. Gate resistors (R10‐R12, R35‐37) prevent parasitic oscillation in the output stage.
Page 4 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Amplifier has open loop gain of 48dB with the cutoff frequency equal to 16kHz. The open loop gain determined by transconductance of the input stage and the common gate stage output impedance. Open loop cutoff frequency determined by the common gate stage output impedance and input capacitance of the output complementary follower.
Close loop gain equal to 20dB. R34 isolates the output of complementary source follower from capacitive load; C18 removes overshoot on the output square wave with capacitive loads.
Operational amplifier U3 with bipolar junction transistors Q6 and Q7 form a servo circuit, which maintains zero dc offset on the output terminal. Time constant of the servo circuit is about 1 sec.
Amplifier has switchable passive cross‐feed circuit (R156‐R162, C132, C133) (Refs. 4,5). Cross‐feed helps to reduce listening fatigue caused by the unnatural stereo image localization, provided by headphones. Cross‐feed circuit can be disabled by switch SW1 without change in the amplifier output voltage. Passive cross‐feed circuit adds 6dB attenuation to the input signal.
Onboard switch mode power supply provides bipolar 24V dc power to MOSFET ripple filters (Q117, Q118). Ripple filters supply left and right channels with bipolar 20V dc, perform slow start and allow using considerable value electrolytic capacitors across the rails. Input of the onboard switch mode power supply is protected with TVS diode D110. External power is galvanically isolated from amplifier circuit.
4 Measurements
Fig.2 Closed‐loop gain for Linear Integrated Systems headphone amplifier as a function of frequency. Cross‐feed circuit is disabled (R158=R160=0)
Page 5 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Fig.3 Closed‐loop phase as a function of frequency. Cross‐feed circuit is disabled (R158=R160=0).
The headphone preamplifier offers wide bandwidth (Fig.2, Fig.3). At 200kHz the frequency response is down by 1dB and phase shift is ‐30°.
Fig.4 Cross‐feed circuit frequency response
Fig.4 shows the frequency response for the crossfeed‐signal (from Right input to Left output) as well as the direct audio signal (from Left input to Left output). The amplitude of the crossfeed‐signal decreases with frequency, and thus mimics the shadowing effect of the head at higher frequencies.
Page 6 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Fig.5 Output impedance of Linear Integrated Systems headphone amplifier as a function of frequency. Output current 10mA
The output impedance (Fig.5) is below 1.5Ω at low and middle frequencies, rising slightly to just under 2.5Ω at the top of the audio band.
Fig.6 Total harmonic distortion plus noise (THD+N) for Linear Integrated Systems headphone amplifier as a function of output voltage.
Page 7 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Figs. 6 plots how the percentage of THD+N in the headphone amplifier output changes into 100Ω, 300Ω and 2kΩ load. The clipping level exceeds 10V rms for 300Ω and 2kΩ. For 100Ω load clipping level is above 7V rms. The increase in distortion into lower impedances caused by limiting of the output current by internal short circuit protection. There is a weak dependance betwenn THD+N and the load impedance.
Fig.7 Total harmonic distortion plus noise (THD+N) for Linear Integrated Systems headphone amplifier as a function of frequency
Fig.7 plots the THD+N percentage against frequency at 1V rms and 5Vrms output. The THD+N rises slightly at the top of the audioband at 5V rms outout
Page 8 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Fig.8 Individual harmonic levels for Linear Integrated Systems headphone amplifier as a function of output voltage. Load 100Ω.
At low output, the distortion is primarily the second harmonic (Fig. 8), at high output levels this is joined by third harmonic at 10dB less level. Higher order products are regularly distributed. Levels of the fourth and fifth harmonic are at least 20dB less than the level of third. Sixth and seventh harmonic levels are about 100dB less than fundamental.
5 References
1 J.Curl, “JC‐2 Preamplifier”, The Audio Amateur, 1977, No 3, p.48
2 J.Curl, “JC‐3 Power Amplifier”, The Audio Amateur, 1981, No 2, p.56, reprinted in Electronics World, April 2000, p.342
3 E.Borbely, "Starter Kits: EB‐604/410 All‐JFET Line Amp", AudioXpress, March 2005, pp.9‐15.
4 D.Danyuk, “Adjustable Crossfeed Circuit for Headphones,” Electronics World, August 2005, p.46
5 “F5‐HA Discrete All FET Class A Headphone Amplifier”, http://xen‐audio.com/documents/f5ha/F5‐HA%20Description%20V1.4.pdf retrieved on 09/01/2016
Related documentation from Linear Integrated Systems:
LSJ74, SST74 ULTRA LOW NOISE SINGLE P‐CHANNEL JFET, datasheet, www.linearsystems.com/assets/media/file/datasheets/LSJ74_SST74.pdf retrieved on 09/01/2016
LSK170 ULTRA LOW NOISE SINGLE N‐CHANNEL JFET AMPLIFIER, datasheet, www.linearsystems.com/assets/media/file/datasheets/LSK170.pdf retrieved on 09/01/2016
LSK489 LOW NOISE LOW CAPACITANCE MONOLITHIC DUAL N‐CHANNEL JFET AMPLIFIER, datasheet, www.linearsystems.com/assets/media/file/datasheets/LSK489.pdf retrieved on 09/01/2016
LSJ689 LOW NOISE LOW CAPACITANCE MONOLITHIC DUAL P‐CHANNEL JFET AMPLIFIER, datasheet, www.linearsystems.com/assets/media/file/datasheets/lsj689part.pdf retrieved on 09/01/2016 retrieved on 09/01/2016
LSK489 Ultra Low Noise JFET, application note, www.linearsystems.com/assets/media/application_notes/LSK489_Application_Note.pdf retrieved on 09/01/2016
LSJ689 Low‐capacitance, monolithic dual P‐Channel JFET, application note, www.linearsystems.com/assets/media/application_notes/app_note_lsj689.pdf retrieved on 09/01/2016
6 Documents
6.1 Linear Integrated Systems headphone amplifier evaluation board schematic diagram
Page 9 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
See attachment
6.2 Linear Integrated Systems headphone amplifier evaluation board parts list
See attachment
6.3 Linear Integrated Systems headphone amplifier evaluation board PCB Layers
The following illustrations portray the Linear Integrated Systems headphone amplifier evaluation board silkscreen, top and bottom layers. These illustrations are not to scale. Gerber files can be obtained from Linear Integrated Systems sales office.
Fig.9 Linear Integrated Systems headphone amplifier evaluation board silkscreen
Page 10 of 10
• 4042 Clipper Court • Fremont, CA 94538 • Tel: 510 490‐9160 • Fax: 510 353‐0261
Fig.10 Linear Integrated Systems headphone amplifier evaluation board top layer
Fig.11 Linear Integrated Systems headphone amplifier evaluation board bottom layer
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Q10
3LS
K17
0CQ
103
LSK
170C
1
3
2U
101A
LSK
489
U10
1ALS
K48
9
2
4
1
R14
927
0R
149
270
D10
8
GR
N
D10
8
GR
N+
C12
233
0u/2
5V+
C12
233
0u/2
5V
D10
2B
ZX84
C15
D10
2B
ZX84
C15
13
R11
2
10R11
2
10
C11
11uC
111
1u
D10
5
DN
P
D10
5
DN
P
Q11
2LS
K17
0CQ
112
LSK
170C
1
3
2
R13
7
10R13
7
10
U10
1BLS
K48
9U
101B
LSK
489
6
8
5
C11
533
nC
115
33n
C11
9
DN
P
C11
9
DN
P
R11
420R
114
20C10
733
nC
107
33n
D10
7R
ED
D10
7R
ED
R12
220
kR
122
20k
R12
620R
126
20
C11
21u
C11
21u
Q10
6FJ
V18
45Q
106
FJV
1845
1
23
D10
6
BA
T54S
D10
6
BA
T54S
C11
8
100p
C11
8
100p
Q11
4
DN
P(L
SK
170)
Q11
4
DN
P(L
SK
170)
1
3
2
R16
310
0kR
163
100k
R11
520R
115
20
5 5
4 4
3 3
2 2
1 1
DD
CC
BB
AA
GN
D
GN
D
GN
D
GN
D
GN
D
GN
D
GN
D
GN
D
GN
D
GN
D
GN
DG
ND
GN
DG
ND
GN
D
+20V
-20V
LIN
RIN
RO
UT
LOU
T
Title
Siz
eD
ocum
ent N
umbe
rR
ev
Dat
e:S
heet
of
<Doc
>C
LSK
489
LSJ6
89 E
VB
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er S
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Cus
tom
33
Mon
day,
Sep
tem
ber 1
2, 2
016
Title
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eD
ocum
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umbe
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Dat
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<Doc
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LSK
489
LSJ6
89 E
VB
Pow
er S
uppl
y, C
onne
ctor
s
Cus
tom
33
Mon
day,
Sep
tem
ber 1
2, 2
016
Title
Siz
eD
ocum
ent N
umbe
rR
ev
Dat
e:S
heet
of
<Doc
>C
LSK
489
LSJ6
89 E
VB
Pow
er S
uppl
y, C
onne
ctor
s
Cus
tom
33
Mon
day,
Sep
tem
ber 1
2, 2
016
C&
K P
N22
SJN
A03
QE
Am
phen
ol A
CJS
-MH
DR
(Mou
ser)
+12V
-12V
LEFT
CH
RIG
HT
CH
J2J4
J3R
159
SW
1
Left
Cha
nnel
Rig
ht C
hann
el
Pow
er S
uppl
y
J1
Cro
ssfe
edE
nabl
e/D
isab
le
12V 380mA
4042
Clip
per C
ourt
Frem
ont,
CA
945
38
Tel:
510
490-
9160
Fax
: 510
353
-026
1
R15
020
kR
150
20k
C13
247
nC
132
47n
MH
2M
HM
H2
MH 1
C27
DN
PC
27D
NP
C25
0.1u
C25
0.1u
R42
DN
P
R42
DN
P
R15
3D
NP
R15
3D
NP
SW
1S
W S
LID
E-D
PD
TS
W1
SW
SLI
DE
-DP
DT
12
345
6
R15
2D
NP
R15
2D
NP
MH
4M
HM
H4
MH 1
R15
520
kR
155
20k
+
C12
910
0u/2
5V+
C12
910
0u/2
5V
+C
128
100u
/25V
+C
128
100u
/25V
D11
0
SM
A6T
22A
Y
D11
0
SM
A6T
22A
Y
J2
PJR
AN
1X1U
02X
(WH
ITE
)
J2
PJR
AN
1X1U
02X
(WH
ITE
)2 3 1
R15
4
100
R15
4
100
+
C13
122
u/10
0V+
C13
122
u/10
0V
R16
2
33k
R16
2
33k
C13
347
nC
133
47n
D10
9MM
BD
7000
D10
9MM
BD
7000
MH
1M
HM
H1
MH 1
+
C12
622
u/10
0V+
C12
622
u/10
0VC
26D
NP
C26
DN
P
R15
1
100
R15
1
100
C13
5
DN
P
C13
5
DN
PQ
118
IRF9
610
Q11
8IR
F961
0
MH
3M
HM
H3
MH 1
+
C12
5
330u
/25V
+
C12
5
330u
/25V
J1 PJ-
202A
J1 PJ-
202A
1 3 2
R15
8
10k
R15
8
10k
Q11
7IR
F710
Q11
7IR
F710
J4
PJR
AN
1X1U
03X
(RE
D)
J4
PJR
AN
1X1U
03X
(RE
D)
2 3 1
D11
1
MM
BD
7000
D11
1
MM
BD
7000
U10
4JC
E06
12D
24U
104
JCE
0612
D24 -Vin1 2
-Vin2 3Com1 9-Vout 11+Vout14 Com216 +Vin122 +Vin223
R15
7
33k
R15
7
33k
C28
DN
PC
28D
NP
J3 AC
JS-M
HD
R
J3 AC
JS-M
HD
R
5 2 3 6 41
R15
9
PTD
902-
1025
K-A
103
R15
9
PTD
902-
1025
K-A
103
R16
0
10k
R16
0
10k
R16
1
5.1k
R16
1
5.1k
+
C13
0
330u
/25V
+
C13
0
330u
/25V
+
C12
7
470u
/25V+
C12
7
470u
/25V
R15
6
5.1k
R15
6
5.1k
LSK489 LSJ689 EVB Revised
: Friday, Sep
tember 09, 2016
Revision: C
Bill Of Materials
Item
Quan
tity
Reference
Part
PCB Footprint
Description
Man
ufacturer Part
Number
Distributor Part Number
(Digikey, M
ouser)
124
C1,C2,C6,C7,C8,C10,C1
4,C15,C16,C17,C21,C23,
C101,C102,C106,C107,C
108,C110,C114,C115,C1
16,C117,C121,C123
33n
1206
0.033µF 100V Ceram
ic Capacitor
C0G
C3216C0G2A333J160AA445‐15415‐6‐ND
24
C3,C20,C103,C120
10u/100V
CPCYL1/D.325/LS.125/.034
10µF 100V Aluminum Capacitor
Radial
UFG
2A100MPM1TD
493‐10867‐1‐ND
36
C4,C22,C104,C122,C125
,C130
330u/25V
CPCYL1/D.400/LS.200/.034
330µF 25V Aluminum Capacitor
Radial
UFG
1E331MPM1TD
493‐10914‐1‐ND
423
R8,R9,C9,C13,C19,C24,
C26,C27,C28,C34,R38,R
46,R108,R109,C109,C11
3,C119,C124,C134,R138
,R146,R152,R153
DNP
805
54
C11,C12,C111,C112
1u
1206
1µF 100V Ceram
ic Capacitor X7R
C3216X7R2A105M160A
A
445‐4468‐1‐ND
62
C18,C118
100p
805
100pF 100V Ceram
ic Capacitor C0G
CGA4C2C0G2A101J060
AA
445‐6951‐1‐ND
71
C25
0.1u
805
0.10µF 100V Ceram
ic Capacitor X7RC2012X7R2A104K125A
A
445‐1418‐1‐ND
82
C126,C131
22u/100V
CPCYL1/D.325/LS.125/.034
22µF 100V Aluminum Capacitor
Radial
UKZ1H220MPM
493‐3193‐ND
91
C127
470u/25V
CPCYL1/D.400/LS.200/.034
470µF 25V Aluminum Capacitor
Radial
UFW
1E471MPD1TD
493‐10998‐1‐ND
10
2C128,C129
100u/25V
CPCYL1/D.325/LS.125/.034
100µF 25V Aluminum Capacitor
Radial
UPW1J101MPD6
493‐1937‐ND
11
2C132,C133
47n
1206
0.047µF 100V Ceram
ic Capacitor
C0G
C3216C0G2A473J115AC445‐172673‐1‐ND
12
4D1,D2,D101,D102
BZX84C15
SOT23
Zener Diode 15V 225mW
BZX84C15LT1G
BZX84C15LT1GOSCT‐ND
13
4D3,D8,D103,D108
GRN
LED_0805
Green
569nm LED
Indication ‐
Discrete 2.1V
LTST‐C171GKT
160‐1423‐1‐ND
14
4D4,D7,D104,D107
RED
LED_0805
Red
631nm LED
Indication ‐
Discrete 2V
LTST‐C171KRKT
160‐1427‐1‐ND
15
2D5,D105
DNP
SOT23
16
2D6,D106
BAT54S
SOT23
Diode Array 1 Pair Series
Connection Schottky 30V 200mA
BAT54SLT1G
BAT54SLT1GOSCT‐ND
17
2D109,D111
MMBD7000
SOT23
Diode Array 1 Pair Series
Connection Standard 100V 200mA
MMBD7000LT3G
MMBD7000LT3GOSCT‐ND
18
1D110
SMA6T22AY
SMA
TVS DIODE 18.8VWM 39.3VC SMA
SMA6T22AY
497‐10939‐1‐ND
19
1J1
PJ‐202A
PJ‐202A
Power Barrel Connector Jack
2.00mm ID
(0.079"), 5.50mm OD
(0.217") Through
Hole, R
ight Angle
PJ‐202A
CP‐202A‐ND
20
1J2
PJRAN1X1U02X (WHITE)
PJRAN1X1U
RCA Phono Connectors 1 POS RA
PH JK W
HITE
PJRAN1X1U02X
502‐PJRA
N1X
1U02
X
21
1J3
ACJS‐M
HDR
ACJS‐M
HDR
Phone Connectors 1/4" PHON SKT
STER
EO
ACJS‐M
HDR
523‐AC
JS‐M
HDR
22
1J4
PJRAN1X1U03X (RED
)PJRAN1X1U
RCA Phono Connectors 1 POS RA
PH JK RED
PJRAN1X1U03X
502‐PJRA
N1X
1U03
X
23
4MH1,M
H2,M
H3,M
H4
MH
MTG
H125‐PLATED
24
8Q2,Q8,Q9,Q10,Q102,Q
108,Q109,Q110
SST74B
SOT89
Transistor, P‐Channel, Single, JFET
25
8Q3,Q4,Q5,Q12,Q103,Q
104,Q105,Q112
LSK170C
SOT23
Transistor, N‐Channel, Single, JFET
26
2Q6,Q106
FJV1845
SOT23
TRANS NPN 120V 0.05A SOT‐23
FJV1845FM
TF
FJV1845FM
TFCT‐ND
27
2Q7,Q107
FJV992
SOT23
TRANS PNP 120V 0.05A SOT‐23
FJV992FM
TF
FJV992FM
TFCT‐ND
28
4Q13,Q14,Q113,Q114
DNP(LSK170)
SOT23
29
4Q15,Q16,Q115,Q116
DNP(SST74)
SOT89
30
1Q117
IRF710
TO220
MOSFET
N‐CH 400V 2A TO‐220AB IRF710PBF
IRF710PBF‐ND
31
1Q118
IRF9610
TO220
MOSFET P‐CH 200V 1.8A TO‐220AB
IRF9610PBF
IRF9610PBF‐ND
32
6R1,R4,R34,R101,R104,R
134
5.1
1210
RES SMD 5.1 OHM 1% 1/2W
ERJ‐14BQF5R1U
P17267CT‐ND
33
8R2,R3,R24,R40,R102,R1
03,R124,R140
1k
805
RES SMD 1K OHM 1% 1/8W
ERJ‐6EN
F1001V
P1.00KCCT‐ND
34
4R6,R49,R106,R149
270
805
RES SMD 270 OHM 1% 1/8W
ERJ‐6EN
F2700V
P270CCT‐ND
35
14
R10,R11,R12,R23,R35,R
36,R37,R110,R111,R11
2,R123,R135,R136,R13
7
10
805
RES SMD 10 OHM 1% 1/8W
ERJ‐6EN
F10R0V
P10.0CCT‐ND
36
12
R13,R14,R15,R26,R27,R
28,R113,R114,R115,R1
26,R127,R128
20
805
RES SMD 20 OHM 1% 1/8W
ERJ‐6EN
F20R0V
P20.0CCT‐ND
37
12
R19,R20,R32,R33,R41,R
119,R120,R132,R133,R
141,R151,R154
100
805
RES SMD 100 OHM 1% 1/8W
ERJ‐6EN
F1000V
P100CCT‐ND
38
4R21,R39,R121,R139
1M
805
RES SMD 1M OHM 1% 1/8W
ERJ‐6EN
F1004V
P1.00MCCT‐ND
39
4R22,R122,R150,R155
20k
805
RES SMD 20K OHM 1% 1/8W
ERJ‐6EN
F2002V
P20.0KCDKR‐ND
40
2R25,R125
51
805
41
2R44,R144
2k
1210
RES SMD 2K OHM 1% 1/2W
ERJ‐14NF2001U
P2.00KAACT‐ND
42
2R45,R145
200
805
RES SMD 200 OHM 1% 1/8W
ERJ‐6EN
F2000V
P200CTR
‐ND
43
2R63,R163
100k
805
RES SMD 100K OHM 1% 1/8W
ERJ‐6EN
F1003V
P100KCCT‐ND
44
2R156,R161
5.1k
805
RES SMD 5.1K OHM 1% 1/8W
ERJ‐6EN
F5101V
P5.10KCCT‐ND
45
2R157,R162
33k
805
RES SMD 33K OHM 1% 1/8W
ERJ‐6EN
F3302V
P33.0KCDKR‐ND
46
2R158,R160
10k
805
RES SMD 10K OHM 1% 1/8W
ERJ‐6EN
F1002V
P10.0KCCT‐ND
47
1R159
PTD
902‐1025K‐A103
PTD
902
Potentiometer 10K AUDIO
PTD
902‐1025K‐A103
652‐PTD9
02‐102
5KA1
03
48
1SW
1SW
SLIDE‐DPDT
PN22SJNA03QE
Pushbutton Switch DPDT Standard
Through
Hole, R
ight Angle
PN22SJNA03QE
CKN1191‐ND
49
2U1,U101
LSK489
SOIC‐8/TO‐71
N‐Channel Transistor, JFET, 6
Leads, Low Noise, Low Capacitance,
Monolithic Dual
50
2U2,U102
LSJ689
SOIC‐8/TO‐71
P‐Channel Transistor, JFET, 6 Leads,
Low Noise, Low Capacitance,
Monolithic Dual
51
2U3,U103
AD8510
SOIC‐8
J‐FET Amplifier 1 Circuit 8‐SOIC
AD8510ARZ
AD8510ARZ‐ND
52
1U104
JCE0612D24
JCE06
DC/DC CONVER
TER +/‐24V 6W
JCE0612D24
1470‐1924‐5‐ND
53
4standoff
HEX
STA
NDOFF 4‐40 BRASS 1/4"
8713
36‐8713‐ND
54
4nut
#4‐40 Hex Nut 0.250"
HNZ 440
H216‐ND
55
4lock waher
WASH
ER SPLIT LO
CK #4
4693
36‐4693‐ND
56
4socket for
U1,U2,U101,U102 TO‐
71
6 Position Socket Connector 0.100"
(2.54mm) Through
Hole Gold
803‐87‐006‐10‐001101 1212‐1229‐ND