CDB5471 Datasheet, PDF (6/26 Pages) Cirrus Logic – Evaluation Board and Software

CDB5471
supply, the “VD+” banana connector post can be
used to independently supply a separate digital
power supply to the input of the CS5471 (VD+
pin), the 4.096 MHz oscillator (U1), and circuitry
for the parallel port interface. This is controlled by
the setting on HDR18.
The user should note that the CS5471 can operate
with a digital supply voltage of either +3V or +5V.
This voltage is defined as the voltage presented
across VD+ and DGND.
2.2.3 Charge Pump Options
The output from CS5471’s charge-pump driver pin
(CPD) can be used to generate a -2V supply when
the proper jumper settings are selected on HDR9.
This -2V supply can be used as the negative power
supply connection for the CS5471’s VA- pin. Re-
ferring to Figure 1, circuitry for a charge-pump cir-
cuit is included on-board. The charge pump circuit
consists of capacitors C11, C12, and C36, and di-
odes D1 and D2.
As an alternative to using the charge pump circuit,
the user can supply an off-board -2V DC power
source to the “A-” banana connector. This option
is controlled by the setting on HDR9.
2.3 Eval Board Control - Headers/Switches
Table 2 lists the various adjustable headers and
switches on the CDB5471 Evaluation Board, as
well as their default settings (as shipped from the
factory). The header settings can be adjusted by the
user to select various options on the evaluation
board. These options are described further in the
following paragraphs.
Power Supplies
Analog Digital
A+
+3
+3
+3
+3
+3
+3
+3
+3
+3
+3
+3
+3
+3
+3
NC
+3
+3
NC
+3
+5
+3
+3
+5
+3
+3
+5
NC
+3
+5
NC
+5
+3
+5
Power Post Connections
A-
GND
D+
-2
0
+3
+5 V_IN
NC
HDR9
A- _{O O}
CPD O O
HDR17
+5V_IN O O
A+
OO
-2
0
NC
NC
A- O O +5V_IN O O
CPD O O A+
OO
NC
0
+3
NC
A- O O +5V_IN O O
CPD O O A+
OO
NC
0
NC
NC
A- O O +5V_IN O O
CPD O O A+
OO
-2
0
NC
+5
A- O O +5V_IN O O
CPD O O A+
OO
NC
0
NC
+5
A- O O +5V_IN O O
CPD O O A+
OO
-2
0
+5
NC
A- O O +5V_IN O O
CPD O O A+
OO
NC
0
+5
NC
A- O O +5V_IN O O
CPD O O A+
OO
-2
0
+5
+5
A- _{O O} +5V_IN O O
CPD O O A+
OO
NC
0
+5
+5
A- O O +5V_IN O O
CPD O O A+
OO
0
+2
+5
NC
A- O O +5V_IN O O
CPD O O A+
OO
Table 1. Power Supply Connections
HDR18
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
VD+ O O
V+ O O
6
DS480DB1