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Issue Date: 23rd August 2005



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

kg 0.8 0.9 0.9
lbs 1.8 2 2

Gallery Court Hankey Place London SE1 4BB UK
Tel: +44 (0)20 7940 2200 Fax: +44 (0)20 7940 2233 1


Safety Precautions & Important Notes 3

540P/640P Main Assembly BOM 4

540P Main PCB Schematic 5

540P Main PCB Layout (Top Side) 6

540P Main PCB Layout (Bottom Side) 7

540P Main PCB BOM 8-9

640P Main PCB Schematic 10

640P Main PCB Layout (Top Side) 11

640P Main PCB Layout (Bottom Side) 12

640P Main PCB BOM 13-15

IC Pin Layout Details 16


1.Check that the rear of the product indicates the correct supply voltage
for you area.

2. The lighting flash with the arrowhead within an equilateral
triangle is intended to alert the user or service agent to the
presence of dangerous voltages within the product enclosure
that may be of sufficient magnitude to constitute a risk of
electric shock to persons.

3. The exclamation point within an equilateral triangle is
intended to alert the user or service agent to the presence of
important operating and maintenance (Servicing) instructions
in the literature accompanying the appliance.

4. This product complies with EEC Low Voltage (73/23/EEC) and
Electromagnetic Compatibility (89/336/EEC) Directives when used and
serviced in accordance with this manual. For continued compliance all
components marked safety and EMC critical must only be replaced by
Cambridge Audio approved parts.

5. Any unauthorised design alterations or additions will void the
manufacturer's warranty; furthermore the manufacturer cannot accept
responsibility for personal injury or property damage resulting therefrom.

6. When servicing, care should be taken to observe the original routing
and dressing of the leads and it should be confirmed that they have been
returned to normal after re-assembly.

Notes on chip component replacement
Never reuse a component that has been removed from a PCB
Notice that the minus side of a tantalum capacitor may be damaged by heat