• on Audio/Video/Photography
  • Published in issue 5/2004 on page 0
About the article

High-End-Preamp, Part 2

High-End-Preamp, Part 2
The modular design and flexibility of the microcontroller program allow the preamplifier to be built exactly according to the individual requirements of its user.The multitude of options for constructing your ‘personalised’ high-end preamplifier mean that you must read this second part of the article before you order the parts and take up your soldering iron. This is because your requirements determine how many circuit boards of which type you will need, as well as which components you will need. You can connect several volume controls in parallel as illustrated in Figure 1, in order to adjust more than two channels at the same time. If you do this, you must interconnect the CS, Mute, SCLK, +5 V and Ground terminals of the circuit boards. SADATO from the first circuit board is connected to SDATI of the next circuit board, and so on. This causes the volume level setting to be communicated to all of the circuit boards.
Downloading of this magazine article is reserved for Elektor Members only.
Already a member? click here to log in.
Gerber file

CAM/CAD data for the PCB referred to in this article is available as a Gerber file. Elektor Members can exclusively download these files for free as part of their Membership. Gerber files allow a PCB to be produced on an appropriate device available locally, or through an online PCB manufacturing service. Elektor recommends its business partner Eurocircuits as the company of choice for its own prototypes and volume production in selected cases.

(main board, 020046-1)
R1 = 27Ohm
R2,R9 = 47kOhm
R3 = 8-way 10kOhm SIL array
R4 = 4-way 10 kOhm SIL array
R5 = 1kOhm 5
R6,R7,R8,R10 = 10kOhm
P1 = 10kOhm preset
P2 = 100Ohm preset
C1,C2,C3,C20 = 10µF 25V radial
C4-C11,C14,C15= 100nF
C12,C13 = 27pF
C16,C17,C18 = 2200µF 25V radial
C19 = 100nF ceramic, lead pitch 5mm
D1 = low-current LED (+ 2-way pinheader)
D2.,D3,D4 = zener diode 5V6, 1.3W
IC1 = PIC18LF452-I/L (PLCC). Blank ICs: Farnell # 400-9654. Programmed ICs: order code 020046-41
IC2 = PGA2311PA from Texas Instruments/Burr-Brown or CS3310 from Cirrus Logic (Crystal)
IC3 = SFH5110 (TSOP1836) (+ 3-way pinheader)
IC4,IC6 = 7805
IC5 = 7905
T1 = BC550C
JP1,JP3 = 2-way pinheader + jumper
JP2 = wire link
K1 = 3-way PCB terminal block, lead pitch 5mm
K2 = = 2-way PCB terminal block, lead pitch 5mm
K3 = 16-way pinheader
K4 = 10-way boxheader, vertical
K5 = 26-way boxheader, vertical
X1 = 10MHz quartz crystal
12 solder pins
External parts:
LCD, 2x16 characters with backlight
12 pushbuttons for chassis mounting
2 Cinch sockets for chassis mounting, isolated and gold-plated
Mains on/off switch, chassis mount
IEC mains appliance socket, chassis mount
Disk, hex and source code files, order code 020046-11 or Free Download.
(relay board, 020046-2)
R1-8 = 10kOhm
R9-R16 = 47kOhm
D1-D8 = 1N4004
D9-D16 = low-current LED
T1-T8 = BC550C
JP1 = 2- way pinheader + jumper
JP2,JP3 = wire link
K1 = 10-way boxheader, vertical
K2 = 2-way PCB terminal block, lead pitch 5mm
RE1-RE8 = RY5W-K (Takamisawa), Conrad Electronics # 502852 (5V/167Ohm )
16 Cinch sockets for chassis mounting, isolated and gold-plated
(asymmetrical PSU, 020046-3)
R1 = 0Ohm 1 5W
Loading comments...