Harman Kardon DPR-2005 Service manual

harman consumer group

SMPS

DPR

1005/2005

Theory of operation and
Service information

Harman Consumer Group 250 Crossways Park Dr. Woodbury, New York 11797
Email [e-mail] Web www.harmanservice.com

By Andy Andersen

Page 2

DPR 1005 / 2005 Block Diagram

Figure 1

A: Voltage Doubler and inrush
B: Over Voltage protect
C: Over Current protect
D: Over Current / Voltage protect

Harman Consumer Group 250 Crossways Park Dr. Woodbury, New York 11797
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Web www.harmanservice.com

E: Multi Voltage SMPS
F: Mosfet Bridge

Page 3

Operation summary

Applied AC line voltage for stand by.
AC line voltage from the relay board goes to connector CN101 and supplies the
voltage for transformer (T101). T101 supplies standby and run voltages +18VAB,
ST5V H8.4V (AC for display). These are the source voltages for the micro (IC62)
for stand by operation.

The applied AC flows through inrush resistors R105 and R104 then rectified by
BD101 to charge C106 and C107. BD101 with C106 and107 are configured as
voltage doublers for 120 operation. Jumper J102 is removed for 240 volt
operation. In either 120 or 240 volt operation 300 volts is developed for
secondary transformer T102.

Stand by to power on
When a High signal is received to connector P-S/W (from micro on main board)
Q201 turns on. Q201 controls optoisolator PC102. PC102 controls U101 at pin 3.
U101 is the driver IC for the SMPS that supplies run voltages +5VA, +5vd, +12V,­12V, +18V, +24V, +44V for the main board.

Other activities at power on
When voltage is developed at D101 and C108 (off T102 of the SMPS) RL101
closes (Pins 3, 4 make contact) A short is produced across the in rush resistors
R105 and R104 (5W 15Ω) Current now flows through RL101 and not the inrush
resistors.

At the same time voltage is applied to relay SK41 (located on the Outlet Board
(rear relay board)). Its contacts are wired across the main power switch and is
used to prevent all the receivers current from flowing through the main power
switch (the switch is rated for 8amps, relay for 20 amps).

Power on
Once the secondary voltages are developed from T102 (smps), the micro sends
a signal to power on (4volt high) the high current SMPS used for the D2 audio
module (cn201 pin 11 P-CON, CN2 pin 1 PWR CNTR-2). IC U1 (PWM KA3525)
pin 10 goes low, and a PWM signal is developed to pins 11,14 (out A/B) to two
driver Transformers (T201, T202), then to a Mosfet Bridge to drive T103.

Harman Consumer Group 250 Crossways Park Dr. Woodbury, New York 11797
Email [e-mail]

Web www.harmanservice.com

Page 4

Details

When AC is applied to the SMPS,
R104 and R105 are used to protect
the inrush to capacitor C106 and
C107. After the voltages are
developed from the SMPS of T102,

Figure 2

For the 120 volt version to develop the 300
volts need to drive the two switch mode
power supplies a bridge diode assembly is
used for the full wave voltage doubler. For
the 230/240 volt SMPS a voltage doubler is
not necessary. To change from 120 to 240
volt operation, remove jumper J102 for the
SMPS part of the power supply. Please note
the standby transformer is specific for each
AC voltage.

Figure 3

Figure 4

DPR. For power down the D/C portion of the power switch sends a command to
the micro to sequence the power supply down, the last step is to release the
power relay.

Relay RL101 closes across the
inrush resistors.

The main power switch cannot
handle the current the DPR can
draw. A relay (SK41) was added to
shunt the power switch at turn on.
When the main switch is turned on
and after voltage is developed in
the stand by supply (from T101)
the relay will close. At this point the
main A/C portion of the power
switch assembly cannot turn off the

Harman Consumer Group 250 Crossways Park Dr. Woodbury, New York 11797
Email [e-mail] Web www.harmanservice.com