UM10155_2
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
User manual
Rev. 02 — 5 September 2006
6 of 12
Philips Semiconductors
UM10155
Discrete Class D High Power Audio Amplifier
4.
Specifications
4.1 Pop-less/click-less start-up and shutdown
A provision has been added to the circuit to provide pop-less/click-less start-up and
shutdown. To make use of the start-up facility, make sure that the supply power (pins J5
and J9) is applied prior to enabling the amplifier (connecting J3 to J4). To benefit from the
pop-less shutdown feature, disable the amplifier (disconnect J3 and J4) prior to removing
the supply power.
4.2 Overcurrent protection
A provision has been added to the circuit to monitor the current flowing through the Power
MOSFETs (Q13 and Q14). The voltage appearing between pins J5 and J6 is proportional
to the current in MOSFET Q14 (ratio: 50 mV/A) and the voltage between J8 and J9 is
proportional to the current in MOSFET Q13 (ratio: 50 mV/A). With the use of an external
Fig 5.
Component layout
Fig 6.
Top silk-screen
001aaf152
001aaf153
J3
J4
J5
J6
J10
J11
J8
J9
J7
J1
J2
C5
class D amp.
version 1.00
international
patent
WO 03/090343
PHILIPS
Q14
Q13
C7
+
+
+
+
+
+
C14
C11
C17
C15
L1
C19
Table 2.
Specifications
Symbol
Parameter
Conditions
Value
V
P
supply voltage
equal positive and negative
supply voltages
±
30 V to
±
45 V
P
L
output power
V
P
=
±
45 V; R
L
= 4
Ω
;
appropriate heatsink needed
200 W (RMS)
η
efficiency
P
L
= 100 W; R
L
= 4
Ω
> 92 %
THD+N
total harmonic
distortion-plus-noise
P
L
= 10 W; frequency range
from 20 Hz to 20 kHz
< 0.03 %
S/N
signal-to-noise ratio
> 120 dB
f
PWM
PWM frequency
idle
~ 400 kHz
V
offset
offset voltage
DC value
< 50 mV
