PKP
VS1000 P
ROGRAMMER
’
S
G
UIDE
VSMPG
11
Peripheral documentation
12
VS1000 System Controller
12.1
General
The System Controller controls various global aspects of VS1000 function such as the
system clock and voltages and I/O pin modes.
12.2
Registers
The System Controller is accessed through 2 registers, SCI_SYSTEM and SCI_STATUS.
12.2.1
SCI_SYSTEM: System Power and Clock Control
SCI_SYSTEM Bits
Name
Bits
Description
SCISYSF_CLKDIV
15
Divide Clock by 2 (for 24 MHz xtal)
SCISYSF_AVDD
14:10
Analog and Usb Voltage setting 2.5V - 3.6V
SCISYSF_IOVDD
9:5
I/O Voltage setting 1.8V - 3.3V
SCISYSF_CVDD
4:0
Core Voltage setting 1.25V - 2.7V
SCI_SYSTEM controls the internal voltage regulator and clock divider of VS1000. Set-
ting the clock divider while PLL is not used (clock multiplier = 1) makes the system run
at considerably slower clock rate, conserving the system power.
Setting bad voltage values can cause malfuntion and/or even physically harm the
device or, in case of IOVDD, even other devices attached to the I/O Pins.
The default values in reset are:
Default Regulator Output Voltages
Net
Default Value
Description
AVDD
2.6 V
Analog and Usb Voltage
IOVDD
1.8 V
I/O Voltage
CVDD
2.2 V
Core Voltage
The Core VDD is directly routed to the DSP core and peripheral logic. AVDD and IOVDD
are routed by the PCB, allowing PCB layout to generate fixed AVDD and IOVDD voltages
(for AVDD and IOVDD there are separate pins for regulator output and chip input).
Rev. 0.20
2011-10-04
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