Sony RM-PJM15, Руководство по обслуживанию

Страница: 35 / 150

3-7
VPL-PX32
1. MAIN CPU: IC3204 (HD64F2633TE)
16-bit, 1-chip microcomputer.
The operating frequency is
Ø
=24.576 MHz which is the 12.288 MHz frequency supplied from the
external crystal oscillator (X3200) multiplied by two times in the internal PLL.
The memories incorporated are the 256 Kbytes FLASH-ROM and 16 Kbytes RAM.
For the terminal functions of the MAIN CPU and the control contents of the external device, refer to
“3-5-4. Terminal Functions of MAIN CPU”.
2. EEPROM: IC3203 (M24C64-WMN)
64 Kbits EEPROM controlled by the 400 kHz IC.
Stores the adjustment values of the projector.
3. Power supply monitoring ICs: IC3201, IC3202 (S-80842, S-80828)
The MAIN CPU operates on the Sub + 5 V and Sub + 3.3 V power supply.
Pin 1 IC3201 monitors the Sub
+
5 V while Pin 1 IC3202 monitors sub
+
3.3 V using their respective
threshold values of 4.2 V and 2.8 V.
When below these threshold values, the reset signal (active = low) is output from Pin 2 of the
monitoring IC, and input to the MAIN CPU reset input terminal (Pin 71 of IC3204).
The CPU is reset by this external reset signal, or the internal reset signal by the WDT (watch dog
timer) in the MAIN CPU.
3-5-2. USB Circuit
VPL-PX32 corresponds to the USB communication as an interface of the personal computer.
The USB circuit mounts the USB hub controller IC and USB projector controller IC in the Y board.
The USB has a tree structure as shown in the figure below.
USB Block
1. USB Hub Controller IC:IC3303 (uPD72012)
The USB communication (US
+
, US
_
) from the personal computer is an IC relaying to the USB
device connected to the lower level.
When connected to the personal computer with a USB cable, + 5 V (VBUS) is supplied from the
personal computer, the Q3307 base becomes high, Q3307 turns ON, the Q3306 base becomes low,
Q3306 turns ON, and the Q3306 collector voltage
=
3.3 V is supplied as the Vcc of IC3303.
When this IC operates normally, the enable signal (active; low) is output to the device in the lower
level connected by the down stream (DS) 1, 2, and 3 from Pins 40, 41, and 42.
USB Hub
Controller
Mouse
Driver
(QB M’t)
USB
Projector
Controller
MAIN
CPU
Power
Controller
(QA M’t)
USB Cable
Host P.C.
USB
Products