Cambridge Audio 640P Service Manual

Gallery Court Hankey Place London SE1 4BB UK
Tel: +44 (0)20 7940 2200 Fax: +44 (0)20 7940 2233
640P/540P
Issue Date: 23rd August 2005
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SERVICE MANUAL
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SPECIFICATIONS:
540P 640P 640P
(MM) (MC)
Max Power Consumption 5W 5W 5W
Gain @ 1kHz 39dB 39dB 55dB
Input Impedance 47k 47k 100R
Nominal Output 300mV 300mV 300mV
Sensitivity for Nominal Output 3.35mV 3.35mV 0.5mV
THD 20Hz-20kHz 0.009% 0.005% 0.002%
RIAA Curve Accuracy +/-0.65dB <+/-0.3dB <+/-0.3dB
25Hz-20kHz 20hz-50kHz 20Hz-50kHz
(Subsonic filter off)
Signal to Noise Ratio >85db >86dB >72dB
Using Audio Precision RIAA-1
with grounded inputs.
Crosstalk @ 20kHz >76dB >83dB >69dB
Dimensions (HxWxD)
mm
46x215x133 46x215x133 46x215x133
inches
1.8x8.5x5.2 1.8x8.5x5.2 1.8x8.5x5.2
Weight
kg
0.8 0.9 0.9
lbs
1.8 2 2
AP18705/1
1

Cambridge Audio 640P Specifications

General

Phono Stage	Yes
Input Impedance	47kΩ (MM), 100Ω (MC)
Dimensions	46 x 215 x 133 mm
Weight	0.9 kg
Frequency Response	20Hz - 20kHz
Gain	39 dB (MM), 55 dB (MC)

Summary

Service Manual Overview

Product Specifications

Technical specifications for Cambridge Audio 640P/540P phono stages, including power, gain, impedance, output, and RIAA accuracy.

Safety and Important Notes

General Safety Precautions

Alerts users to electrical hazards, proper servicing, and the importance of using approved replacement parts.

Component Replacement Guidelines

Notes regarding the reuse of components and potential damage to tantalum capacitors.

Copyright and Legal Information

Copyright Statement

Details copyright ownership and restrictions on reproduction or distribution of the manual.

Bill of Materials

Main Assembly BOM (540P/640P)

List of parts for the main assembly of Cambridge Audio 540P/640P units.

540P PCB Assembly BOM

Detailed Bill of Materials for the 540P printed circuit board, listing resistors, capacitors, and semiconductors.

640P PCB Assembly BOM

Detailed Bill of Materials for the 640P printed circuit board, listing components and their specifications.

Circuit Schematics

540P Main PCB Schematic

Schematic diagram for the main printed circuit board of the Cambridge Audio 540P phono stage.

640P Main PCB Schematic

Schematic diagram for the main printed circuit board of the Cambridge Audio 640P phono stage.

PCB Layouts

540P Main PCB Layout (Top Side)

Visual representation of the component placement and routing on the top side of the 540P PCB.

540P Main PCB Layout (Bottom Side)

Visual representation of the component placement and routing on the bottom side of the 540P PCB.

640P Main PCB Layout (Top Side)

Layout diagram showing component placement on the top side of the 640P PCB.

640P Main PCB Layout (Bottom Side)

Layout diagram showing component placement on the bottom side of the 640P PCB.

Integrated Circuit Pinouts

Main PCB IC Pin Configurations

Pinout diagrams for key integrated circuits used on the main PCB, including voltage regulators and op-amps.