BRUEL & KJAER 5935 - Page 9

Chapter 1 — Functional Description
DC/DC Converter
BE 1300– 12 Dual Microphone Supply Type 5935 1–3
User Guide
Note: Because of the switched mode of operation, the output 0V is not referenced
to the negative terminal of the internal batteries or external source. This is to
reduce noise within the system. See section 3.2.
Fig.1.1 Block diagram of Type 5935
921798e
Overload
Output Ch. 1
(front panel)
Output Ch.2
(front panel)
Output
Swap Switch
Front Panel
Input Socket
LIN
(rear panel)
A-weighting
(rear panel)
0 - 50 dB
10 dB Steps
Heater
+ 24 V
Polarization
Voltage
A/LIN
Switch
Heater
+ 24 V
Polarization
Voltage
0 - 50 dB
10 dB Steps
Front Panel
Input Socket
A/LIN
Switch
LIN
(rear panel)
A-weighting
(rear panel)
DC/DC
Converter
Voltage
Regulator
Voltage
Divider
028200
200 V
Battery
Low
Polarization
Voltage
+ 24 V
– 11 V
+ 11 V
On/Off
Fuse
+ ve
– ve
External
Supply
Input
(8V - 16 VDC)
A Weighting
Filter
Variable Gain
Buffer Amplifier
Overload
Detector
Overload
Detector
Detector
Internal
Battery
Channel 1
Channel 2
Overload
Power On
Variable Gain
Buffer Amplifier
A Weighting
Filter