Alesis CC0, Service Manual

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1.2.7 10-BIT EFT BUS SWITCH
Component
：
74CBT3384A
Major of function is multiplexed address and data bus exchange for CD-BACKUP
mode or USB mode for CD-RW device. When U_ATA_EN is “Low” that bus switch will
exchange CD-RW device for CD-BACKUP multiplexed bus. When U_ATA_EN is “High”
that bus switch will exchange CD-RW device for USB multiplexed bus.
1.2.8 POWER REGION
Component
：
APL1117-33VC-TR (SOT-223)
BA17805FP (SOT-252)
Major of power supply is +5V but some of IC is nec3.3V for system.
Therefore design APL1117-33VC-TR regulator circuit to step-down for +3.3V. Presently
to use +3.3V that include U2, U3 and U7 component. Additional BA17805FP regulator
circuit is provide 5V for LCD component.