3
Figure 1–5. STE Back Panel
1.3 POWER SUPPLY
The 520STE and 1040STE have an integral switching power supply pro5V
and +12V. There is a 2A fuse. Voltage should be adjusted to 5.1V. The power supply
has overcurrent protection; if the fuse is blown, a catastrophic failure is likely, such
as shorted primary
Power Supply Rating
Current out: 3A at 5V, 0.9A at +12V
Max. power in: 33.5W
Typical (in system) Demand
.
Typical current: 1.75A at 5V, 86 mA at + 12V
Max. current: 2.2A at +5V, 90 mA at +12 (during disk access)
1.4 NEGATIVE SUPPLIES
The STE motherboard contains two small switching voltage regulators (the TL497 or
equivalent) that are used to provide additional voltages.
0204 is used to generate the positive and negative voltages for the RS232C line
drivers. These voltages are normally ±12 VDC.
U205 is used to generate a –5 VDC supply for the audio subsection. This output is
heavily filtered to reduce the switching noise that might otherwise appear in the
audio output.
Содержание 1040STE
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Страница 2: ...II Atari STe 520 1040 Computer Field Service Manual Part Number C302481 001 Rev A August 1991...
Страница 23: ...18 Figure 2 8 STE Functional Block Diagram...
Страница 24: ...19 Figure 2 9 STE DMA Block Diagram...
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Страница 53: ...48 Figure 6 1 STE Diagnostic Flow Chart...
Страница 54: ...49 Figure 6 2 STE Diagnostic Flow Chart...
Страница 55: ...50 Figure 6 3 STE Diagnostic Flow Chart...
Страница 56: ...51 Figure 6 4 STE Diagnostic Flow Chart...
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Страница 81: ...ATARI STE TEST FIXTURE TO COMPUTER CONNECTION...