Evaluation Kit for CMX7x6x
PE0601-xxxx
©
2011 CML Microsystems Plc
22
UM0601/2
6
Detailed Description
6.1
Hardware Description
The PE0601 as shipped may not have the optimum configuration or component values for all
function images. Check the PE0601 schematic against recommendations in the specific
CMX7x6x datasheet.
6.1.1 Power Supplies
The board is fitted with six voltage regulators.
U8 and U9 provide the analogue and digital supply rails respectively. U10 provides a separate
supply rail for the CMX7x6x speaker driver and U12 provides an external 1.8 volt supply option
for the CMX7x6x core. The input to these four regulators should be provided by an external 5V dc
regulated power supply, which can be daisy chained from the PE0002 or connected to the board
via connector J16, a push type connector. LED illumination confirms the on-board presence of the
+3.3V dc digital voltage supply.
U17 provides a negative supply rail for the instrumentation interface. If required, an additional –5V
dc regulated supply should be connected at J16. U18 provides a positive supply rail for the
instrumentation interface.
Each supply has a test point where it can be monitored; see Table 2 – Test Points.
6.1.2 Clock Options
The PCB is designed to provide three CMX7x6x device clock options. The board is supplied with
a 19.2MHz oscillator module fitted.
Other options are an external clock source at J5 (not fitted) or a quartz crystal oscillator circuit at
C16, C17 and X2 (not fitted).
Header J6 is used with jumper sockets to select the required option as shown in the table below.
Shaded cells illustrate locations where a jumper socket should be fitted.
Clock Option
J4
Jumper
Position
19.2MHz oscillator
(default)
External Quartz
crystal
1-2
3-4
5-6
7-8
9-10
Table 5 – Clock Select Jumper Positions