high performance power conversion
DATASHEET
Audio Power Board 200
Type: APB 200
Features
•
•
•
•
•
•
•
•
•
Fully integrated Power Supply and 4 Channel Amplifier combination
Freely configurable into 4x SE, 2x SE + 1x BTL or 2x BTL configuration
Quasi-resonant switching technology for high efficiency
Class-D audio amplifiers with audiophile sound quality
High audio output power up to 200W RMS for 1 minute
FTC rated audio output power 90W RMS
Universal mains input voltage: 90 – 264VAC
Low standby power 300mW
Lead free and environmental friendly design (RoHS compliant)
Applications
•
•
•
•
Subwoofers
Active speakers
Multi-channel sound systems
Musical instrument systems
Revision: July 5, 2011
high performance power conversion
General description
The Audio Power Board – APB 200 – is an all-in-one solution for high performance audio
applications. With a minimum of external circuits, the APB 200 quickly builds up into a high
quality audio subsystem.
Besides 4 amplifier outputs the board provides two symmetrical auxiliary output voltages for
analog electronics and an output voltage for digital circuitry, also present in standby mode.
Operating from worldwide mains voltages, without the need to change switch or jumper
settings, the logistic advantages are obvious – only one product that can be sold and
distributed across the globe.
Low power consumption in standby mode is mandatory in today’s world, for companies
taking the lead on environmental responsibility and sustainability. With less than half a watt
the APB 200 does not require an additional standby power supply to achieve very low power
consumption in non-operational mode, while staying active all the time.
Advanced and highly efficient switched mode power conversion optimizes the overall
performance. By using quasi-resonant switching technology losses are minimized and no
massive heatsinks are required. This minimizes dimensions and cost and enables a sleek
industrial design of the end product.
There is no active (linear) analog amplification in the amplifiers. All active components in the
signal path operate in on-off mode. Also the feedback loop consists of only passive
components. This avoids adding any signature or coloration to how the music was mastered
originally.
The power amplifiers, based upon an improved UCD technology, are built from carefully
selected components, giving us full control over every detail of the design needed to realize
this outstanding and audiophile audio power board – APB 200.
Audio power supply section
Quite often the power supply is seen as a commodity item where only voltage and (static)
power rating are considered as major selection criteria.
A power supply however is not just a power supply
Safety, reliability, lifetime and performance of the total application are affected by the power
supply unit and by the interaction between the power supply and the application. Careful
integration and matching of the power supply and the power amplifiers onto one board
overcomes the difficulties often experienced in customers’ end applications.
Dynamic peak power capability
For the best audio performance the converter needs to be capable of delivering high peak
powers to the output almost at an instance. This guarantees a very solid output voltage with
minimal fluctuations of the output voltage due to dynamic loads. This results in excellent
behavior under high dynamic audio loads.
APB 200
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high performance power conversion
UCD power amplifier section
UCD is an analog modulation technique for class-D amplifiers based on a free running
oscillator. The oscillation conditions are created by a phase shift in the feedback loop
between the output terminals and the input of the amplifier.
The UCD technique is characterized by four features:
Feedback directly from the output terminals
The feedback signal is taken directly from the output terminals of the amplifier, thereby
including the output filter in the control loop, virtually eliminating the influence of the filter on
the audio performance. Advantages are a very low output impedance, a stable operation
over a broad range of load impedances from 3Ω to ∞ and the absence of a Zobel network, so
that there is no restriction to output power and duration in the high audio frequency range.
Proportional feedback loop
The feedback loop of the UCD amplifier is proportional in the range of audio frequencies, as
opposed to the often-applied integrating feedback. This gives the UCD amplifier, besides a
superb clipping response, an excellent audio performance over the full audio bandwidth.
No active analog amplification
There is no active (linear) analog amplification in the UCD amplifier cell. All active
components in the signal path operate in on-off mode. Also the feedback loop consists of
only passive components, minimizing the coloration of sound and insuring maximum
transparency.
This opens possibilities to shape the character and quality of the sound by the signal
processing in the end application.
Excellence by simplicity
The high performance of the UCD amplifier is not realized by complex control and
compensation circuits. The strength of this concept lies in its simplicity. Only a bare minimum
of carefully selected components and materials are used.
The combination of these features give the UCD amplifier its transparent character and offers
outstanding value for money.
APB 200
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high performance power conversion
AC MAINS INPUT SPECIFICATIONS
Parameter
Min
AC Input
Voltage
Voltage
Frequency
Typ
Max
Units
Notes
90
115
264
240
VRMS
VRMS
functional, reduced power rating
full specification
48
63
Hz
Standby Power Consumption
115 – 230VAC
Standby
0.3
W
ON, AMPs muted
1.0
W
Active, no audio signal
Dielectric Withstand
6.5
W
3000
VRMS
primary to secondary
Notes
OUTPUT SPECIFICATIONS POWER SUPPLY
Parameter
Symbol
Min
Typ
Max
Units
Output 1
Voltage
+V_aux
20.0
22.0
35.0
V
0.05
0.1
A
–22.0
–35.0
V
–0.05
–0.1
A
6.0
6.25
V
0.2
1.0
A
Current
Output 2
Voltage
–V_aux
Current
Output 3
Voltage
+V_stby
–20.0
5.75
Current
see note 1 and 3
unregulated, see note 2
always present
note 1: maximum allowed capacitive load on Output 1 and Output 2: 220µF each
note 2: unloaded output voltage rises at high audio output power
note 3: all “Max” currents can be applied continuously
OUTPUT SPECIFICATIONS AMPLIFIERS PER CHANNEL
Parameter
AC Output in 4Ω
Power
Power
Power
AC Output in 8Ω
Power
Power
AC Output in 8Ω
Power
Power
Min
Typ
Max
Units
Notes
40 (50)
20
WRMS
WRMS
per channel, see note 4
< 1 min. (in 3.5Ω)
< 5 min. (FTC)
5
WRMS
20
WRMS
5
WRMS
80 (100)
50
WRMS
WRMS
continuous
2 channels bridged
< 1 min. (in 7Ω)
< 5 min. (FTC)
12.5
6
WRMS
APK
protection level
8
∞
∞
Ω
Ω
20
25
mΩ
SE
SE
BTL
Power
Peak output current
continuous
see note 5
< 5 min. (FTC)
continuous
Load impedance
ZL,SE
ZL,BTL
3
6
Output impedance
ZO
ZO
Output voltage offset
4÷8
200
–30
30
note 4: external heatsinking is required to fulfill the power specifications.
note 5: max. power limited by supply voltage
APB 200
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per channel
2 channels bridged
per channel
@ 20Hz – 5kHz
mΩ
@ 20kHz
mV
shorted input
high performance power conversion
AUDIO SPECIFICATIONS
Parameter
Min
Voltage gain
SE
BTL
19.2
25.2
Audio frequency range
fL
fU
fAUDIO
Typ
20
26
Max
20.8
26.8
10
36k
20
Input impedance ZIN
24k
3
Dynamic range
90
Idle hum + noise
THD+N @ 1kHz SE
Notes
dB
dB
inverting
per channel
2 channels bridged
Hz
Hz
–3dB , AC coupled
–3dB
Hz
+0.1 / –1dB
kΩ
1kHz
dB
200
µVRMS
0.2
0.8
%
%
%
20Hz ÷ 20kHz, AES17
per channel
@ 1W in 4Ω
@ 100mW ÷ 20W in 4Ω
@ 40W in 4Ω
0.2
0.8
%
%
%
2 channels bridged
@ 1W in 7Ω
@ 100mW – 40W in 7Ω
@ 100W in 7Ω
0.02
THD+N @ 100Hz
Units
BTL
0.05
CONTROL CHARACTERISTICS
Parameter
Min
Typ
Max
Units
_STBY as input, see note 6
ON
2.4
6
6.25
V
X014 pin 6, bidirectional signal
Normal operation
0.8
V
STBY mode, +V_stby present
STBY
_STBY as output
ON
FAULT
Notes
2.4
6
6.25
0.8
V
V
Normal operation
Monitor internal fault
_AMP_disable as input, see note 7
ON
MUTE
4
4.5
5.5
0.8
V
V
X011 pin 10, bidirectional signal
Normal operation
Amplifiers muted
_ AMP_disable as output
ON
FAULT
4
4.5
5.5
0.8
V
V
Normal operation
Monitor internal fault
MON_temp output
OK
Over Temperature
4
4.5
5.5
0.8
V
V
X011 pin 11
Normal operation
Amplifiers muted
MON_over_current output
OK
Over Current
4
4.5
5.5
0.8
V
V
X011 pin 12, see note 8
Normal operation
Monitor amplifiers over current
note 6: Pull this pin down (with Open Collector) or leave open. Do not apply an external voltage. Internal pull up resistor to +V_stby = 10kΩ.
note 7: Pull this pin down (with Open Collector) or leave open. Do not apply an external voltage. Internal pull up resistor to +4.5V ~ 5kΩ.
note 8: Over current signal are pulses only and can be as short as 1µsec.
note 9: Allowed load impedance to GND_AMP on all outputs: >22kΩ, except _AMP_disable: >100kΩ
APB 200
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high performance power conversion
GENERAL SPECIFICATIONS
Parameter
Min
Temperature range
Storage
–25
70
ºC
0
50
ºC
Operating, ambient air
Conducted EMI
Safety
Typ
Max
Units
Notes
full specification
FCC 47 part 15 Class B, IEC 55013 (CISPR 13)
IEC 60065 7th edition
UL 60065 7th edition
MECHANICAL CHARACTERISTICS
Parameter
Weight
Overall Dimensions
APB 200
Typ
Units
325
195 x 100 x 37
g
mm
6 of 16
Notes
LxWxH
high performance power conversion
CONNECTOR PIN-OUT
X010
JST B2P-VA
X011
JST B12B-PH
(counterpart: JST VAR-2)
(counterpart: JST PHR-12)
PIN
DESCRIPTION
PIN
DESCRIPTION
L
N
1
2
AMP_in_1–
GND-AMP
3
4
5
6
AMP_in_2–
GND_AMP
AMP_in_3–
GND_AMP
1
2
X014
JST B6B-PH
(counterpart: JST PHR-6)
PIN
1
2
3
4
DESCRIPTION
+V_aux
GND_aux
–V_aux
GND_stby
7
8
9
10
11
AMP_in_4–
GND_AMP
GND_stby
_AMP_disable
MON_temp
5
+V_stby
12
MON_over_current
6
_STBY
X012
JST B4P-VH
X013
JST B4P-VH
(counterpart: JST VHR-4)
(counterpart: JST VHR-4)
PIN
DESCRIPTION
PIN
DESCRIPTION
GND_AMP
AMP_out_1
AMP_out_2
GND-AMP
1
2
3
4
GND_AMP
AMP_out_3
AMP_out_4
GND-AMP
1
2
3
4
CONNECTOR LOCATIONS
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high performance power conversion
BLOCK DIAGRAM
_STBY
MAIN
OVP
UVLO
ON/STBY
Control
ON/MUTE
Control
MON_over_current
MON_temp
_AMP_disable
DC Error OTP
OCP
Enable
AMP
+
−
AMP_out_1
AMP_in_2–
+
−
AMP_out_2
AMP_in_3–
+
−
AMP_out_3
AMP_in_4–
+
−
AMP_out_4
X011
AMP_in_1–
GROUND CONNECTION DIAGRAM
audio
circuits
+V_aux
GND_aux
R131
4.7Ω
C131
100nF
–V_aux
AMP
GND_AMP
chassis
R133
4.7Ω
C133
100nF
R132
4.7Ω
C132
100nF
digital
circuits
+V_stby
GND_stby
X135
mounting hole
to chassis
APB 200
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X012
STBY
X013
Mains IN
X010
PSU
V_stby
V_aux
X014
high performance power conversion
Control Signals
_STBY
When the mains voltage is applied to X010, the unit is fully functional by default. The main
PSU is operational and the amplifiers are active. To enter standby mode, pull down signal
_STBY with an open collector.
In case of an internal fault a transistor in the amplifier module pulls down the _STBY signal.
This shuts down the main PSU. By monitoring the _STBY signal it is possible to detect such
a fault condition.
V_stby
10k
Fault monitoring
1
_STBY
Main PSU ON
Standby
33k
GND_stby
optional
see text
DC Error
OVP
Amplifier Module
Optional resistor: The _STBY signal is pulled up to 6V through a 10kΩ resistor. When using
5V logic in the external support electronics, it is allowed to add a 33kΩ resistor between
_STBY and GND_stby to reduce the voltage level of the _STBY signal to below 5V.
_AMP_disable
When leaving this pin open, the amplifiers are active by default. To mute the amplifiers
(oscillation stops), pull down this pin with an open collector.
In case of an amplifier fault, circuitry in the amplifier module pulls down the _AMP_disable
signal. This mutes the amplifiers. By monitoring the _AMP_disable signal it is possible to
detect such a fault condition. Optionally, the MON_over_current and MON_temp signals can
be monitored separately.
+4.5V
~5k
Fault monitoring
1
_AMP_disable
Amplifiers ON
+4.5V
Mute
GND_AMP
Over Temperature
Monitoring
1
Over Current
Monitoring
1
10k
One-Shot
250msec
MON_temp
MON_over_current
1
1
OCP
OTP
Amplifier Module
APB 200
10k
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UVLO
high performance power conversion
The diagram above shows a simplified representation of the internal circuitry. The
MON_over_current signal are short pulses only (~1µsec). The 250msec timer stretches
these pulses to allow the amplifier to recover from an Over Current failure.
Protections
To protect the amplifier against accidental abuse, following protections are implemented:
• DC error on the amplifier outputs
• Over and under voltage on PSU
• Over temperature
• Over current / short circuit
DC error
When a DC voltage appears on any of the the amplifier outputs, the main supply voltage is
removed until the DC error disappears. The supply restarts automatically after 2 – 3 seconds.
Over Voltage
The PSU is protected against a loss of feedback in the control loop causing the output
voltages to rise. The PSU shuts down and latches. To recover from this situation (which is
usually caused by a permanent defect) remove the mains voltage for at least 20 seconds.
Under Voltage
The amplifiers have an Under Voltage detection for monitoring the supply lines. The
amplifiers are activated only when the supply voltage is high enough to operate the amplifiers
within specification and safe limits. This also prevents plops at ON and OFF switching.
Over temperature
The temperature is monitored at different locations in both the amplifiers and the power
supply. When any of these spots exceed a certain temperature, all amplifiers are muted.
Restart occurs automatically after the temperature has dropped by approximately 10°C.
Over current / short circuit
The output current of each amplifier is monitored. When exceeding a certain threshold, the
amplifier mutes for 250ms. Restart occurs automatically. If the over current condition
remains, the muting will cycle causing repetitive audio holes.
The +V_stby output has an over current and short circuit protection. The V_aux outputs
however are only protected with small resistors in series which will fuse in case of an
overload. The use of current limited post regulators on these outputs is recommended.
All protections work autonomously. Some protection signals can be monitored, as described
above, but there is no need to act on any of these signals.
APB 200
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high performance power conversion
Thermal design
The APB 200 makes use of surface mount components to minimize board space. To fully
utilize the power rating of the amplifier channels, additional heatsinking is required to remove
excess heat from these surface mount components.
It is recommended to mount the circuit board to a metal (front) plate, preferrably covering at
least the size of the APB 200. A standard size aluminum square bar, cut to length, and a gap
pad act as a thermal bridge between the circuit board and the metal (front) plate. This
construction forms a simple yet highly effective cooling method.
M3x6
PCB
spring washer M3
Gap Pad 100x11x1 mm
metal stud M3x10
ALU bar 99x10x10 mm
toothed washer M3
Metal plate 1 – 1.5mm
apply a thin film
of heatsink compound
M3x6
M3x6
Gap pad material options
3M:
type 5595 (1mm thick)
Bergquist:
type K2000S40
APB 200
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high performance power conversion
Single Ended or Bridged Tied Load operation
STANDARD SINGLE ENDED CONFIGURATION
AMP_out_1
AMP_in_1–
AMP_out_2
AMP
Channel 1
AMP
Channel 2
GND_AMP
GND_AMP
Amplifier Module
AMP_in_2–
Load
Load
Amplifier Module
Amplifier inputs should be driven with a low impedance source (≤100Ω), preferably with the
output of an opamp. To correct for the inverting gain of the power amplifier, also have an
inverting gain in the pre-amp stage. The circuit below shows an example for a line level input.
1k
47k
100k
Line IN
220k
-
470nF
1nF
AMP_in_1–
+
To avoid supply pumping in a stereo 2x Single Ended configuration, invert the phase of the
input signal and speaker terminals of one of the two channels.
BRIDGED TIED LOAD (BTL) CONFIGURATION
AMP_out_1
AMP_in_1–
AMP_out_2
AMP
Channel 1
AMP
Channel 2
GND_AMP
AMP_in_2–
GND_AMP
Amplifier Module
Load
Amplifier Module
The amplifier can also be used in a Bridged Tied Load (BTL) configuration, delivering up to
100W RMS into 7Ω. Connect the outputs according to the diagram above. The circuit below
shows an example of a pre-amp stage for this configuration.
1k
47k
100k
Line IN
220k
1nF
-
470nF
AMP_in_1–
AMP_out_1
+
AMP
Channel 1 & 2
47k
47k
AMP_in_2–
AMP_out_2
+
Amplifier Module
Load
The same also applies to amplifier channels 3 and 4. Note that channel 1 can only be
bridged with channel 2, and channel 3 only with channel 4.
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high performance power conversion
Performance data
Frequency response
+1
+0.5
+0
-0.5
d
B
r
-1
-1.5
-2
-2.5
-3
10
20
50
100
200
500
Hz
1k
2k
5k
10k
20k
40k
Frequency response in 4Ω
Idle noise SE
+0
-10
-20
-30
-40
-50
d
B
r
-60
-70
-80
-90
-100
-110
-120
-130
-140
-150
20
50
100
200
500
1k
2k
5k
10k
20k
Hz
Idle noise, 0dB = 40W in 4Ω, Amplifier Ch 1 (red), Amplifier Ch 2 (blue) – Ch 3 and 4 are comparable
Idle noise BTL
+0
-10
-20
-30
-40
-50
d
B
r
-60
-70
-80
-90
-100
-110
-120
-130
-140
-150
20
50
100
200
500
1k
2k
Hz
Idle noise, 0dB = 100W in 7Ω
APB 200
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5k
10k
20k
high performance power conversion
Output impedance SE
500m
400m
T T
300m
200m
100m
Ω
70m
50m
40m
30m
20m
10m
20
50
100
200
500
1k
2k
5k
10k
20k
10k
20k
Hz
Output impedance vs. frequency, Single Ended output to GND
Output impedance BTL
500m
400m
T T
300m
200m
100m
Ω
70m
50m
40m
30m
20m
10m
20
50
100
200
500
1k
2k
5
10
5k
Hz
Output impedance vs. frequency, BTL output
THD+N vs. output power SE
1
0.5
0.2
%
0.1
0.05
0.02
0.01
100m
200m
500m
1
2
20
50
100
W
THD+N vs. POUT @ 1kHz, Amplifier Ch 1 (red), Amplifier Ch 2 (blue) – Ch 3 and 4 are comparable
APB 200
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high performance power conversion
THD+N vs. output power BTL
1
0.5
0.2
%
0.1
0.05
0.02
0.01
100m
200m
500m
1
2
5
10
20
50
100
W
THD+N vs. POUT @ 200Hz
ORDER INFORMATION
Version
standard
APB 200
Product description
HE1298033-01
Audio Power Board APB 200
15 of 16
# Units per box/pallet
high performance power conversion
For further information you may contact:
Heliox B.V.
The Netherlands
Email: info@heliox.nl
Internet: http://www.heliox.nl/
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