Samsung SF-830, Руководство по обслуживанию

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3-40
CIRCUIT DESCRIPTION
Samsung Electronics
Repair Manual
3-7-5. RING DETECTION PART
RING SIGNALS from the LINE section (TIP, RING)are further passed through C5, R3, ZD1, and ZD2 and ends up at U9, (PC
814). U9 then detects above RING SIGNAL and passes the output to MAIN B’D. The wilre diagram’s C5 is RINGER CAPAC-
ITOR and it normally uses 1UF/250V.
A R3 limits AC current and controls upper and lower REN meter.
3-8 SMPS (Switching Mode Power Supply) Unit.
3-8-1 SMPS SPECIFICATIONS
The SMPS (Switching Mode Power Supply) Unit used here is a PWM (Pulse Width Modulation) type power supply unit that
supplies DC+5V to controller and control panel, and DC+5V, DC+24V and DC+12V to the engine. It also supplies AC power
to fixer heat lamp.
No. Output Channel Ch.1 Ch.2 Ch.3
1 Channel Name +5.1V +24.0V +12.0V
2 Rated Output Voltage +5.1V +24.0V +12.0V
3 Rate Output Current 2A 2.5A 1.0A
4 Maximum Load Current 3A Continued 3.5A Continued 1.0A Continued
and Load Pattern
5 Load Change Range 0.5~2.0A 0.3~2.5A 0.2~1.0A
6 Rate output voltage +5.1V±5% +24.0V±10% +12V±5%
(For rated I/O) (+4.84~+5.35V) (+21.60~+26.40V) (+11.40~+12.60V)
7 1) Total Output Voltage Including All Including All Including All
Deviation +5.1V±5% +24.0V±10% +12V±5%
(Input, Load, Temp., Aging) (+4.84~+5.35V) (+21.60~+26.40V) (+11.40~+12.60V)
2) Dynamic Input Change Including Set Error Including Set Error Including Set Error
3) Dynamic Load Change
8 Refer to ripple & noise 27) 150mVp-p or less 500mVp-p or less 150mVp-p or less
9 Refer to load short and Must not ignite or Output voltage must Must not ignite or
overload protection 23) generate smoke shutdown withing generate smoke
Refer to load short and when output shorted the range of when output shorted
overload protection 23) for 5 sec. 3.5A~6.5A for 5 sec.