HP M35EU Reference Manual

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12

MOBILE 3500 EXPANSION UNIT

This chapter briefly describes the optional Mobile 3500 Expansion Unit (M35EU) .
The M35EU comes with two speakers and a subwoofer, a fixed optical drive bay,
a MultiBay, and an integrated AC adapter.

The MultiBay accepts an optional hard disk drive, LS-120 diskette drive, Zip drive or
second hard drive (with adapter) . The optical disk bay accepts 24x Max CD-ROM
or DVD-ROM.

The integrated AC adapter converts AC voltage into low voltages to drive the DC-DC
converter and to recharge the battery pack.

Refer to Chapter 11, “Mass Storage,” for more information on the optical disc bay and

the MultiBay.
Figure 12-1 shows a block diagram of the M35EU.

M35EU

MultiBay

Optical

Disc Bay

AC Input

Figure 12-1. Mobile 3500 Expansion Unit, Block Diagram

45W AC-DC

Converter

DC-DC

Converter

Li-Ion

Battery

Pack

+5 VDC

+3.3 VDC

Mobile 3500 Expansion Unit 12-1

Mobile 3500 Expansion Unit Audio System

The M35EU’s sound system consists of two speakers and a dual voice coil woofer.
Several amplifiers and thirteen stages of fixed equalization complete the system.

The core subsystems incorporated into the audio design are:

■ Two 20x40 mm, high performance, 4 ohm, neodynium magnet loudspeakers

■ Custom high performance, 67 mm diameter, dual voice coil woofer

■ Two low distortion amplifires:
❏ Stereo 2.0 watt RMS per channel
❏ Bridged 4.0 watt RMS, low frequency amplifier

■ Thirteen stages of fixed equalization

■ Gain staging to compensate for different input levels generated by various audio

sources (CD-/DVD-ROM and wavetable)

Integrated Power Supply

The integrated power supply converts 110/220 VAC into low voltage DC to drive the
DC-DC converter and to recharge the battery pack. The output of this AC/DC supply is
approximately +10 to +14.5 V.

12-2 Mobile 3500 Expansion Unit