Philips JL2.1E Service Manual page 20

EN 20 5. JL2.1E AA
Standby Supply starts running.
+5V2, 1V2Stb, 3V3Stb and +2V5D become present.
In case of PDP 3V3 Vpr to CPU PDP becomes present.
All I/O lines have a "high" default state:
- Assert the Viper reset.
- Sound-Enable and Reset-Audio should remain "high".
- NVM power line is "high", no NVM communication possible.
Initialise I/O pins of the st-by µP, start keyboard scanning, RC
detection, P50 decoding. Wake up reasons are "off".
Switch "low" the NVM power reset line. Add a 2ms delay before
trying to address the NVM to allow correct NVM initialization.
Switch Main Supply to "on" by switching "low" the
ON-MODE and the POD-MODE I/O lines.
+5V, Vtun, +8V6, +12VSW, +5V2S, Vsound
and +12/24V are switched "on".
Wait 50ms and then start polling the detect-
5V, detect-8V6 and detect-12V every 40ms.
300 ms after POD-MODE
Activate +5V supply detection algorithm.
Detect-12V received within
2000 ms after POD-mode
Activate +12V supply
detection algorithm
Enable the DC/DC converter for +1.2V.
Start polling the detect-1V2 every 40ms
To part B
Service Modes, Error Codes, and Fault Finding
Off
Mains is applied
St-by µP resets
The availability of the supplies is checked through "detect" signals (delivered by
dedicated detect-IC's) going to the st-by µP. These signals are available for
+12V, +8V6, +5V, +1V2 and +2V5. A "low" to "high" transition of the signals should
occur within a certain time after toggling the standby line. If an observer is
detected before the time-out elapses, of course, the process should continue in
Detect-5V
received within
toggle?
Yes
No
toggle?
Yes
No need to wait for the 8V6 detection at this point.
Detect-1V2
No
received within
250ms?
To part B
Figure 5-3 "Off" to "Semi Stand-by" flowchart (part 1)
Stand by or
Protection
If the protection state was left by short circuiting the
SDM pins, detection of a protection condition during
startup will stall the startup. Protection conditions in a
playing set will be ignored. The protection mode will
not be entered.
- Switch Sound-Enable & Reset-Audio "high".
They are "low" in the standby mode if the
standby mode lasted longer than 2s.
order to minimize start up time.
No
+5V error
SP
+12V error
SP
within 2000 ms after POD-mode toggle?
Startup shall not wait for this detection
+1.2V error
To part B
action holder: MIPS
action holder: St-by
autonomous action
Detect-8V6 received
and continue startup.
No
activate +8V6 supply
+8V6 error
detection algorithm
To part B
F_15710_152a.eps
Yes
To part B
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