ON Semiconductor NCP2824FCT2GEVB User Manual
© Semiconductor Components Industries, LLC, 2012
May, 2012 − Rev. 2
1 Publication Order Number:
EVBUM2110/D
NCP2824FCT2GEVB
NCP2824FCT2 Evaluation
Board User's Manual
Overview
The NCP2824 is a Filterless Class D amplifier capable of
delivering up to 2.4 W to a 4 W load with a 5 V supply
voltage. With the same battery voltage, it can deliver 1.2 W
to an 8 W load with less than 1% THD+N. The Non-clipping
function adjusts automatically the output voltage in order to
control the distortion when an excessive input is applied to
the amplifier. This adjustment is done thanks to an
Automatic Gain Control circuitry (AGC) built-in the chip.
A simple Single wire interface allows to enable/disable the
non Clipping function and also to configure the maximum
distortion level in the output. A programmable power limit
function is also embedded in order to protect speakers from
damage caused by an excessive sound level.
The intent of the evaluation boards is to illustrate typical
operation of the NCP2824 device for laboratory
characterization. The NCP2824FCT2GEVB schematic is
depicted in Figure 2.
Figure 1. NCP2824FCT2GEVB Board Picture
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EVAL BOARD USER’S MANUAL
NCP2824FCT2GEVB
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2
BOARD SCHEMATIC
Figure 2. NCP2824FCT2GEVB Evaluation Board Schematic
Title
Size Document Number Rev
Date: Sheet
of
NCP2824 EVB TLS−P−001−A−0310−DR
NCP2824 EVB
Custom
11
U1
NCP2824
INP
A1
VDD
A2
OUTP
A3
AGNDB1NCB2PGND
B3
INM
C1
CNTL
C2
OUTM
C3
C1
100n
C2
100n
C3
4.7μF
0
OUTN
OUTP
0 0
J1
Jumper3
1
1
2
2
3
3
0
Vdd
J2
Jumper2
1
1
2
2
J3
Jumper2
1
1
2
2
0
0
J4
CUT H
112
2
J5
CUT H
112
2
INPF
J6
TP 1.0D
1
1
J7
TP 1.0D
1
1
J8
TP 1.0D
1
1
CNTL
J9
TP 1.0D
1
1
Vdd
J10
TP 1.0D
1
1
J11
TP 1.0D
1
1
J13
GND
112
2
0
0
INMF
J14
CON2
112
2
0
J15
CON2
1
1
2
2
C4
NC
0
C5
100μF−NC
C6
4.7μF
0
J16
FIX 3.2 H
1
1
J17
FIX 3.2 H
1
1
J18
FIX 3.2 H
1
1
J19
FIX 3.2 H
1
1
0
J12
TP 1.0D
1
1
ENABLE− SINGLE WIRE
BOARD FIXATION HOLES
POWER SUPPLY
SPEAKER CONNECTION
NCP2824FCT2GEVB
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3
OPERATION
The operating power supply of the NCP2824 is from 2.5
to 5.5 V. The absolute maximum input voltage is 7.0 V. A
power supply set to 3.6 V and current limit set to at least
1.5 A must be connected to J14 connector to powering the
NCP2824EVB/D. Also to compensate for parasitic
inductance of wires between the power supply and the
evaluation board it is highly recommended to connect a
470 mF electrolytic capacitor to bypass J14 terminal. Like
this the device can be evaluated under powering condition
very similar that battery power supplies.
Performances of EVB Solution
To be as close as possible with final handset application,
the design of this power conversion solution used small size
footprints where possible. Changing components may
positively or negatively impact the evaluation board
performance illustrated in Figure 3 to 8. For more
information please refer to the NCP2824 datasheet.
Single Wire Interface Operation
The single wire interface allows changing the default
configuration of the NCP2824.
After Wake up, the NCP2824 is configured with:
• AGC enable
• Non Clip + Power limit
• Gain = 18 dB
• THD max = 1%
The following table described all the NCP2824
configurations.
Table 1. NCP2824 CONFIGURATION
Pulse
Counting
Register Description
01
AGC
AGC disable
02 AGC Enable
03 Reset Reset configuration
04
Gain
Control
Gain = 12 dB
05 Gain = 18 dB
06
THD
Control
1%
07 2%
08 4%
09 6%
10 8%
11 10%
12 15%
13 20%
14 NC+L Non Clip + Power limit
15 NC Non Clip only
16
Power
Limit
Control
0.45 V
Peak
17 0.9 V
Peak
18 1.35 V
Peak
19 1.8 V
Peak
20 2.25 V
Peak
21 2.7 V
Peak
22 3.15 V
Peak
23 3.6 V
Peak
Single Wire commands can easily be emulated using a
pulse generator configured in accordance with the Single
wire specification, for more information about timings
please refers to NCP2824 datasheet.
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