Cirrus Logic CDB61880 - Manual (Page 5)

CDB61880
DS450DB1 5
2. BOARD COMPONENT DESCRIPTIONS
2.1 Power Connections
Power for the CDB61880 evaluation board is sup-
plied by an external +3.3 V DC power supply. A +5
V DC power supply can also be connected to the
on-board control logic. The LED labeled “D3” will
illuminate when power is supplied to the on-board
control logic.
- Connect the +3.3 VDC power supply to the +3
V binding post and the +5 VDC power supply to
the +5 V binding post if 5 Volt logic is required
- Jumper J13 shown in Figure 2 allows all the
external logic on the evaluation board to be
connected to either +3 V or +5 V binding post.
- To measure the current consumption of only
the CS61880 device, place a short block on
Jumper J13 to connect the Vlogic power
supplies to the +5 V binding post. This will
isolate the CS61880 device from all the on-
board logic, to allow the current measurement
to be made at the +3 V binding post.
2.2 Master Clock Selection
In both Hardware and Host modes, the MCLK pin
is configured by placing a short block on one of the
positions of bed stake header J1.
Figure 3 shows
the different positions of the J1 bed stake header.
- A 2.048 MHz clock oscillator is provided on the
evaluation board for use as the on-board clock
source for all E1 modes.
- A BNC connector (labeled J16) provides the
connection for an external clock source.
J 1 3
3 V
5 V
O n -b o a rd lo g ic c o n n e c te d
to + 3 V b in d in g p o s t
O n -b o a rd lo g ic c o n n e c te d
to + 5 V b in d in g p o s t
V L O G IC
J 1 3
3 V
5 V
V L O G IC
Figure 2. On-board Logic Power Selection
MCLK
J1
Data Recovery Mode
EXTERNAL SOURCE HIGH OSCILLATOR GND
MCLK
J1
External Clock Source
HIGH OSCILLATOR GND
J1
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HIGH OSCILLATOR GND
J1
HIGH OSCILLATOR GND
On-board Oscillator
MCLK
MCLK
EXTERNAL SOURCE
EXTERNAL SOURCE EXTERNAL SOURCE
Figure 3. Master Clock Selections