De low-noise labvoeding van Elektor is een volledig analoge, instelbare, symmetrische unit met gemiddeld vermogen, zonder schakelende of digitale componenten. De uitgangsspanning is instelbaar tussen 0 V en ±22 V, en de uitgangsstroom kan worden ingesteld van 0 A tot 1 A. Doordat elke vorm van schakeltechniek wordt vermeden, levert het ontwerp extreem weinig ruis. Voor de weergave van beide uitgangsspanningen en -stromen worden vier kleine analoge paneelmeters met draaispoel gebruikt.
De meeste moderne laboratoriumvoedingen en AC-adapters maken gebruik van schakelende technieken. Zelfs de beste uitvoeringen vertonen onvermijdelijk hoogfrequente rimpel en andere schakelartefacten op hun uitgang, die het testen van gevoelige analoge schakelingen kunnen verstoren en metingen van kleine signalen kunnen beïnvloeden. Om dit te voorkomen, is het concept hier een volledig analoge voeding. Hoewel deze minder efficiënt is dan vergelijkbare schakelende voedingen, is de lagere efficiëntie bij gebruik op de testbank nauwelijks van belang en zorgt deze voor schonere en betrouwbaardere meetresultaten.
Omdat veel analoge schakelingen een symmetrische voeding vereisen, levert dit ontwerp positieve en negatieve uitgangsspanningen van gelijke grootte. Een kleine hoeveelheid afregeling is beschikbaar om eventuele onbalans te compenseren. Uiteraard is ook een instelbare stroombegrenzing aanwezig.
Specificaties
Uitgangsspanning
0…+22 V, 0, −22 V
Uitgangsstroom
0…+1 A, 0…−1 A
Ruis
−85 dBV (bij 0,95 A/20 V, B = 22 kHz)
−84 dBV (bij 0,95 A/20 V, B > 500 kHz)
Rimpelspanning
50 µVRMS (bij 950 mA/20 V, B = 22 kHz, voornamelijk 100-Hz-component)
Inbegrepen
3x printplaten: regelaar (PCB-1), netfilter (PCB-2) en transformator (PCB-3)
Alle componenten, behalve de AC-transformatoren
4x draaispoelmeters
Extra onderdelen voor de bedrading (draden, banaanstekkerbussen, IEC-voedingsmodule, enz.)
Niet inbegrepen
De drie AC-transformatoren
Een behuizing
Onderdelenlijst
Voor de regelaar-printplaat (240386-1)
Weerstanden (250 mW, 1%)
R1 = 12 Ω
R2, R8, R37, R62 = 1 MΩ
R3, R7, R10, R13, R17, R20, R22, R30, R35, R42, R45, R47, R55, R60 = 100 Ω, 600 mW
R4, R5 = 4.7 kΩ
R6 = 100 kΩ
R9, R12, R14, R36, R38, R39, R61, R63, R66, R72, R78, R79 = 10.0 kΩ, 600 mW
R11 = 9.76 kΩ, 600 mW
R15, R40 = 44.2 kΩ, 600 mW
R16, R41, R77 = 1 kΩ
R18, R43 = 1.5 kΩ, 1 W, 5%
R19, R44 = 470 Ω, 1 W, 5%
R21, R46 = 330 Ω, 600 mW
R23, R24, R48, R49 = 1.0 Ω, 1 W
R25, R50 = 1 kΩ, 1 W, 5%
R26, R28, R51, R53 = 1.000 kΩ 0.1%, 15 ppm/C
R27, R29, R52, R54 = 10.00 kΩ 0.1%, 15 ppm/C
R31, R56 = 1.2 kΩ, 1 W, 5%
R32, R57 = 47 kΩ
R33, R58 = 270 Ω
R34, R59 = 27 kΩ
R64, R69 = 12.0 kΩ
R65 = 3.0 kΩ, 600 mW
R67, R80 = 470 Ω, 600 mW
R68, R70 = 6.8 kΩ, 600 mW
R71 = 30.0 kΩ,, 600 mW
R73, R74, R75, R76 = 10 MΩ
P1, P2, P3 = 10 kΩ, 200 mW, 20%, potentiometer, 1 turns, single, lin., panel mount
P4, P5 = 500 Ω, 500 mW, 10%, trimmer, 25 turns, 3296Y-1-501LF Bourns
P6, P7 = 10 kΩ, 500 mW, 10%, trimmer, 25 turns, 3296Y-1-501LF Bourns
Condensatoren
C1 = 100 nF, 50 V, 10%, ceramic X7R, LS 5 mm
C2, C3, C6, C7, C30 = 10 µF, 63V, 20%, LS 2.5 mm, 3000hours@105°C
C4, C5, C8, C9, C13, C14, C18, C19, C23, C24, C28, C29, C31, C32, C38, C39 = 100 nF, 250 V, 10%, PET, LS 7.5 mm
C10, C20 = 47 nF, 100 V, 5%, PET, LS 5 mm
C11, C21 = 10 nF, 100 V, 5%, PET, LS 5 mm
C12, C22 = 220 µF, 35 V, 20%, 0.024 Ω, LS2.5/3.5 mm, Ir 3.4 A, 2000hours@125°C, polymer
C15, C25 = 120 µF, 50 V, 20%, ESR 0.02 Ω, Diam. 10 mm max., LS 5 mm
C16, C26 = 15 nF, 100 V, 5%, PET, LS 5 mm
C17, C27 = 47 nF, 100 V, 5%, PET, LS 5 mm
C33, C34 = 22 µF, 50 V, 20%, LS 2 mm, 10000 hours @ 105°C
C35, C36, C44, C45 = 1 µF, 100 V, 10%, LS 5 mm, ceramic X7R
C37 = 100 uF, 50 V, 20%. LS 3.5 mm
C40, C41, C42, C43, C46, C47, C48, C49 = 1000 µF, 50 V, 20%, LS 5/7.5 mm, Ir 3.32 A, 10000hours@105°C, D 16 mm
C50, C51, C52, C53 = 47 nF, 100 V, 10%, ceramic X7R, LS 5 mm
Spoelen
L1, L2 = 4.7 µH, 3.2 A, 0.033 Ω, LS 5 mm, RLB0914-4R7ML Bourns
L3 = Commom mode choke, 14.5 mH, 3 A, SSRH24NH-30145 Kemet
Halfgeleiders
D1, D2, D3, D4, D5, D9, D10, D11, D15 = BAT85, DO-34
D6, D7, D12, D13 = SR560, DO-201AD
D8, D14, D16 = 1N4148, DO-35
D17 = Zenerdiode, 5.6 V, 0.5 W, DO-41
D18, D19 = 1N4004, DO-41
D20, D21 D22, D23 = V30100CI-M3/P, dual common cathode, TO-220
D24 = Zener diode, 30 V, 1 W, DO-41
LED1, LED2 = LED, red, T-1 (3 mm)
LED3, LED4 = LED, green, T-1 (3 mm)
TVS1, TVS2 = BZW50-33B, R6
T1, T2, T4 = BC337.25, TO-92
T3 = NJW0302G, TO-3P
T5, T6, T8 = BC327.25, TO-92
T7 = NJW0281G, TO-3P
T9 = BD139, TO-126 (SOT-32)
IC1 = LM334Z, TO-92
IC2 = LM4040AIZ-5.0/NOPB, TO-92 (TO-226AA-3)
IC3, IC4 = OPA2992IDR, SOIC-8
IC5, IC6 = OPA4992IDR, SOIC-14
IC7 = OPA992IDBVR, SOT-23-5
IC8 = LM339N, DIP-14
IC9 = LM317, TO-220
IC10 = LM337, TO-220
Overige
F1, F2 = 5×20 mm fuse, 1.6 A, fast acting
HS1, HS2 = Heatsink MC33271 (for T3/T7), 2.7°C/W, PCB mount, height 63.5 mm
K1, K4 = 3-way screw terminal block, LS 3.5 mm, max. 1.5 mm²
K2, K3 = 3-way screw terminal block, LS 3.5 mm, max. 1 mm²
M1, M3 = Moving coil meter, Range 30 V, type 91C4, 45×45 mm
M2, M4 = Moving coil meter, Range 1 A, type 91C4, 45×45 mm²
RE1 = Relay DPDT,5V, UA2-5NU
Diversen
3× 3-way screw terminal block, LS 3.5 mm, max. 1 mm² (for P1, P2, P3)
4× Pin header, 1×2, vertical, pitch 2.54 mm (for LED1, LED2, LED3, LED4)
4× Pin socket, 1×2, vertical. pitch 2.54 mm (for LED1, LED2, LED3, LED4)
2× Heatsink FK222SA220, 20°C/W, PCB mount (for IC9 & IC10)
2× Mica thermal pad for TO-220, 12×18×0.05 mm (for IC9 & IC10)
2× Insulating bushing IB 6, TO-220 (for IC9 & IC10)
2× Ceramic thermal pad, 23×20×2 mm (for T3 & T7)
2× PCB Fuse Holder, for 5×20 mm fuse, 10 A (for F1, F2)
2× Cover for PCB Fuse Holder, transparent (for F1, F2)
2× 2-way screw terminal block, LS 3.5 mm, max. 1 mm² (for M1 & M3)
2× 2-way screw terminal block, LS 3.5 mm, max. 1.5 mm² (for M2 & M4)
8× M3 solder lug, thickness 0.35 mm (for M1…M4)
M4 solder lug, thickness 0.35 mm (to connect 4 mm banana connectors)
Screened cable, 1 pair, 2×24 AWG/0.22 mm², 1 m (for P1, P2 & P3)
IC socket, DIP, 14 contacts (for IC8)
M3 washer, plain, steel
M3 screw, 16 mm, steel, pan head
M3 nut
M3 spring washer
50 mm M3 standoff, steel, male-female
12 mm M3 standoff, steel, male-female
10 mm M3 standoff, steel, male-female
M3 screw, 8 mm, steel, pan head
Voor de netfilter-printplaat (240386-2)
Weerstand
R1 = 220 kΩ, 1 W, 500 V, 5%
Condensatoren
C1, C2 = 470 nF, 305 VAC, Class X2, 11 × 27 mm max., LS 15/22.5 mm
C3, C4, C5, C6 = 2.2 nF, 300 VAC, Class Y2, 13 × 4 mm, LS 10 mm, PP
Spoelen
L1, L2 = Common-mode choke, 6.8 mH, 1.7 A, TDK B82732R2172B030
Halfgeleider
MOV1 = TVS varistor, 300 VAC, S14K300 (230 VAC, B72214S0301K101) and SK14K150 (150 VAC, B72214S0151K101)
Overige
K1, K2 = 3-way screw terminal block, LS 7.62 mm
F1 = Time-delay fuse, 0.5 A (230 VAC) or 1 A (115 VAC)
Diversen
1× Fuse holder, 5×20 mm, 10 A, 500 VAC
1× Transparent fuse cover
4× 10 mm M3 standoff, steel, male–female
4× M3 screw, 8 mm, steel, pan head
4× M3 nut
Voor de transformator-printplaat (240386-3)
Weerstanden
R1, R2 = 2.7 kΩ, 600 mW, 1%
R3 = 10.0 kΩ, 600 mW, 1%
Condensator
C1 = 220 µF, 50 V, 20%, Ø10 mm, LS 5 mm, 4000 h @ 105°C
Transformatoren (niet inbegrepen in deze kit!)
TR1, TR2, TR3 = 2×7 V, 25 VA, PCB-mounted toroid, 70060K Talema
Halfgeleiders
D1–D4 = 1N4148, DO-35
D5, D6 = 1N4004, DO-41
D7 = Zener 5.6 V, 1.3 W, DO-41
LED1 = LED, red, T-1 (3 mm)
IC1, IC2 = MOC8021M, CTR ≥ 1000%, DIP-6
Overige
F1, F2, F3 = 160 mA time-delay fuse (230 VAC) or 315 mA time-delay fuse (115 VAC)
K1 = 2-way screw terminal block, LS 7.62 mm
K2 = 3-way screw terminal block, LS 3.5 mm, max 1.5 mm²
K3, K4 = 3-way screw terminal block, LS 3.5 mm, max 1 mm²
RE1, RE2 = Relay DPDT, 5 A/250 VAC / 24 VDC
Diversen
1× Pin header 1×2, pitch 2.54 mm + matching socket for LED1
3× Fuse holder 5 × 20 mm, 10 A, 500 VAC + transparent cover
3× M4 screw, 8 mm, pan head + washer for TR1-TR3
8× M3 screw, 8 mm, pan head + nut + washer
8× 10 mm M3 standoff, steel, male–female
2× IC socket, DIP-6 for IC1 & IC2
Extra onderdelen
1 m red insulated wire, stranded, 1.5 mm²
0.5 m blue insulated wire, stranded, 1.5 mm²
0.5 m black insulated wire, stranded, 1.5 mm², 0.5 m
2 m red insulated wire, stranded, D 0.56 mm (0.25 mm²)
2 m black insulated wire, stranded, D 0.56 mm (0.25 mm²)
0.5 m Multicore Cable, Flexible, 3 Core, 0.75 mm² (24 x 0.2 mm)
Red banana socket
Black banana socket
Blue banana socket
Green banana socket
IEC Power Entry Module with switch, IEC C14
3 crimp terminals, FASTON, 4.75 x 0.81 mm
3 knobs
Links
Elektor Labs
JumpStarter Page
Artikel (deel 1)
Artikel (deel 2)
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