VS1000 Datasheet, PDF (12/23 Pages) List of Unclassifed Manufacturers – Ogg Vorbis Player IC with USB and NAND FLASH Interface

VLSI
Solution ^y
VS1000b
VS1000
6. VS1000 FUNCTIONAL BLOCKS
6 VS1000 Functional Blocks
LEFT
RIGHT
CBUF RCAP
VHIGH
PWRBTN
AVDD1
AVDD2
AVDD3
USBP
USPN
XCS/GPIO1[0]
SCLK/GPIO1[1]
SI/GPIO1[2]
SO/GPIO1[3]
RX/GPIO1[5]
TX/GPIO1[4]
XTALO
XTALI
Data/
GPIO0[0...7]
Control/
GPIO0[8...14]
Stereo
Earphone
Driver
Stereo
DAC
Common
Voltage
Driver
Voltage
Monitor
USB
Serial
Data/
Control
Interface
UART
Clock
NAND
Flash
Interface/
General IO
reset
VSDSP4
processor
Reference
Regulator
Regulator
Regulator
<1.6V
X RAM
X ROM
Y RAM
Y ROM
I RAM
I ROM
IOVDD
AVDD
CVDD
TEST XRESET
IOVDD1
IOVDD2
6.1 Regulator Section
Figure 2: VS1000 Block Diagram
The VHIGH pin in the regulator section is used as a common main power supply for voltage regulation. This
input is connected to three internal regulators, which are activated when the PWRBTN pin is set high for about one
millisecond, so that AVDD starts to rise and reaches about 1.5 V. After the PWRBTN has given this initial start
current, the regulators reach their default voltages even if the PWRBTN is released. VHIGH must be sufficiently
(about 0.3 V) above the highest regulated power (normally AVDD) so that regulation can be properly performed.
The PWRBTN state can also be read by software, so it can be used as one of the user interface buttons.
A power-on reset monitors the core voltage and asserts reset if CVDD drops below the CMON level. It is also
possible to force a reset by keeping PWRBTN pressed for longer than approximately 5.6 seconds. A watchdog
counter and the XRESET pin can also generate a reset for the device.
Resets do not cause the regulators to shut down, but they restore the default regulator voltages. After boot the
firmware and user software can change the voltages.
Return to power-off is possible only with active software control (VSDSP writes the regulator shutdown bit), or
when VHIGH voltage is removed for a sufficiently long time. In the default firmware player the power button has
to be pressed for 2 seconds to make the software powerdown the system and turn the regulators off.
Version 1.0, 2007-09-11
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