LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
Copyright © 2000
Rev. 0.1, 2004-09-30
LX1722SM AUDIOMAX
EVALUATION KIT
USER’S GUIDE
TM ®
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
Copyright © 2000
Rev. 0.1, 2004-09-30
LX1722SM Evaluation Board Quick Start Guide
The LX1722SM Evalua tion Board is a fully functional stereo class-D amplifier. Connection to a single power supply, two
speakers, and an audio source is all that is required to begin evaluating the amplifier. The amplifier will support continuous
output power levels up to >60W x 2 into 4 ohm load (<1% THD+N), using small outline Surface Mount type MOSFETs.
Board Setting
1. Power and Ground Connections: The terminal JP1 is for the power supply connection. Vcc is connected to the
positive polarity of th e power supply or battery (+7V ~ +25V ); the GND is connected to the negativ e polarity of the
power supply or battery. Please make sure your power supply polarity connection and supply voltage is correct
before you start to evaluate the board.
2. Speakers Connections: JP5 and JP6 are the speaker outputs. JP5 is for the left channel (CH1) and JP6 is for the right
channel (CH2). Connect speaker “+” and “-“ to “LOUT+/ROUT+” and “LOUT-/ROUT-“ of JP5/JP6. This
evaluation board is designed for standard 4 ohm speaker loads. For different impedance speakers, the output filter
values should be modified to optimize the output frequency response. Please see AudioMAX Design Resource
(AN-16) for LC filter values.
3. Audio Input Connections: JP2, JP2A, RCA1 and RCA2 are the audio input connections. JP2/JP2A support
differential audio inputs, and RCA1/RCA2 are for the single-ended audio inputs. When audio inputs are differential,
the positive audio inputs are connected to LIN+/RIN+ pin, while the negative inputs are connected to LIN-/RIN- pin
of the JP2/JP2A terminals. J1 and J2 jumpers are left open when using differential inputs. When audio inputs are
single-ended, the inputs audio source can either be connected to terminal JP2/JP2A, or to RCA1/RCA2. In this
single-ended connection, jumpers J1 and J2 must be closed so that the LIN-/RIN- audio inputs are connected to
Ground.
4. SLEEP/MUTE Connections: JP4 is the jumper selection for ON/OFF of SLEEP and MUTE functions. To enable
the amplifier, both jumpers should be set to “OFF” (SLEEP is OFF, and MUTE is OFF).
5. Pre-amp Output Connections: JP3 is the header for stereo, single-ended pre-amp outputs, “LPREOUT – GND –
RPREOUT”. These outputs are provided to drive other crossover networks or to support additional power
amplifiers such as for a Subwoofer speaker system.
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
Copyright © 2000
Rev. 0.1, 2004-09-30
APPLICATION SCHEMATIC
RIN+
ON
GND
These traces keep as
short as posible.
PGND
Vcc
ON
2. PGND and GND plate is expected, they
are devided by the center of LX1722
PGND
3. Red havey line means needing heavy
duty trace or copper
RIN-
OFF
SLEEP
5. Chassis GND circles the whole board
on bothe top layer and bottom layer.
4. LPWM+,LPWM-,RPWM+,RPWM- MUST BE KEPT
AS SHORT AS POSSIBLE.
Keep this trace as short as
possible, directly from R7
pin
1. Star connection is expected for PGND;
LIN+
OFF
MUTE
LIN-
Keep this trace as short as
possible, directly from R6
pin
RPREOUT
LPREOUT
GND
Cn
RP-
LIN-
_MUTE
Vcc
LIN+
RN-
ROUT+
RIN-
LN+
Vcc
Vcc
LN-
LOUT-
LOUT+
ROUT-
LP+
Vcc
RP+
RPREOUT
SLEEP
Vcc
Vcc
LP-
LISN
LISN
chassis_gnd
chassis_gnd
LPWM-
LPWM+
RISN
RPWM-
RISN
Cpwm
Clock
LPREOUT
RIN+
GND
PGND
PGND
PGND
PGND
pgnd
RN+
GND
PGND
PGND
RPWM+
1
2
1
2
3
1 2
3 4
5 6
1 2
LFAOUT
1
CPWM
2
RPWM
3
_LMUTE
4
LEAOUT
5
LEAIN
6
VREF
7
CLOCK
8
GND
9
V25
10
LIN+
11
LIN-
12
LAMPOUT
13
RIN+
14
RIN-
15
RAMPOUT
16
SLEEP
17
STATUS
18
_RMUTE
19
REAIN
20
REAOUT
21
RFAOUT
22 RFBK- 23
RFBK+ 24
RISN 25
NC 26
PVDD 27
CP 28
PGND 29
RN+ 30
RP+ 31
RP- 32
RN- 33
LN- 34
LP- 35
LP+ 36
LN+ 37
PGND 38
PVDD 39
CN 40
VDD 41
LISN 42
LFBK+ 43
LFBK- 44
1
2
1
1
1
2
1
2
1 2
1
2
1
2
1
2
1
2
R18
1.43K 1%
C33
0.68uF/50V
JP2A
HEADER 2
C38
0.1uF/25V
JP3
HEADER 3
R22
10k
C17 4.7uF/25V,TANT
+
C20 4.7uF/25V,TANT
+
JP4
HEADER 3X2
C37
0.1uF/25V
R23
10k
C29
0.68uF/50V
C30
0.68uF/50V
Q1B
Si7501DN
C34
0.47uF/50V
R20
15/1W
Q2A
Si7501DN
L4
15uH
C31
0.47uF/50V
C13 1uF/10V,TANT
+
C27
4.7nF
C35
0.1uF/25V
J2
JUMPER
C36
0.1uF/25V
U1
LX1722CDB
R1 10k
R5 49.9k 1%
R2 56.2k 1%
R4 56.2k 1%
RCA1
RCA JACK
R3 10k
C7 100pF
Q3A
Si7501DN
C10 100pF
G1
chassis_gnd
C21
47uF/25V
+
C12 100pF
Q4B
Si7501DN
C18
47uF/25V
+
C9 22pF
Q2B
Si7501DN
C11 22pF
L3
15uH
C8 0.1uF/25V
C19
0.1uF/25V
C22
0.1uF/25V
C3 0.47uF
JP6
Teminal 2
C4 0.47uF
C32
0.68uF/50V
C5 0.47uF
RCA2
RCA JACK
C6 0.47uF Q3B
Si7501DN
R19
1.43K 1%
Q1A
Si7501DN
J1
JUMPER
R6
0.020/1W
R16
1.43K 1%
Q4A
Si7501DN
R7
0.020/1W
R17
1.43K 1%
L100 FERRITE/SM
C25
4.7nF
C26
4.7nF
JP2
HEADER 2
R21
15/1W
JP1
Teminal 2
C28
4.7nF
JP7
HEADER 2
JP5
Teminal 2
L1
15uH
C1
1000uF/25V
+
L2
15uH
C2
0.1uF/25V
RFBK-
Vcc
RFBK-
LFBK+
Cn
RFBK+
LFBK-
Cn
Vcc
RFBK+
LFBK-
Vcc
LFBK+
Vcc
Figure 1 - LX1722SM Schematic
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
Copyright © 2000
Rev. 0.1, 2004-09-30
LX1722 BLOCK DIAGRAM
SLEEP
VREF
V25
CN
PVDD
CP
LP+
LN+
LP-
LN-
LFAOUT
LFBK-
LFBK+
VDD
LISN
CLOCK
RPWM
CPWM
LEAOUT
LEAIN
LAMPOUT
LIN-
LIN+
LMUTE
UVLO
&
REFERENCE
OUTPUT
DRIVERS
&
LOGIC
FAULT
TIMER
5V
Reference 28
10
7
17
CLK
OSC
SYNC
+
-220mV
PVDD
MUX
MUTE
MUTE
11
5
6
13
4
12
2
3
8
42
41
1
44
FEEDBACK AM P
ERROR AMP
CURRENT SENSE
INPUT AMP
43
27,39
36
37
34
35
S
R
Q
Q
CLK
5V
Reference 40
2.5V
2.5V
Figure 2 – LX1722 Block Diagarm
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
Copyright © 2000
Rev. 0.1, 2004-09-30
BILL OF MATERIALS
MISCELLANEOUS COMPONENTS
Line
Item Part Description Manufacturer & Part # Case Reference
Designators Qty
1 IC, Controller MICROSEMI LX1722CDB QSOP 44
U1 1
2 IC, P/N – Channel MOSFET VISHAY Si7501DN 1212-8 Q1, Q2, Q3, Q4 4
3 Ferrite Bead MURATA BLM41P102SGPT 1206 L100 1
4 Inductor, 15uH ABRACON AIMT-103-15µH TH
L1, L2, L3, L4 4
5 Phono Jack, 90° Nickel Plated, White MOUSER 161-4214 TH
RCA1 1
6 Phono Jack, 90° Nickel Plated, Red MOUSER 161-4214 TH
RCA2 1
7 Header, Str. .100” Center, 2Pos ANY 87220-2 TH
J1, J2, JP2, JP2A, JP7 5
8 Header, Str. .100” Center, 3Pos ANY 87220-3 TH
JP3 1
9 Header, Double Row .100” Center, 6Pos ANY 1/87215-2 TH
JP4 1
10 Shorting Jumpers, Open Top, Black MOUSER 151-8030 TH
J1, J2 2
11 Terminal Block 2Pos 5mm BLOCK MASTER 301-021-1000 TH JP1, JP5, JP6 3
CAPACITORS
Line
Item Part Description Manufacturer & Part # Case Reference
Designators Qty
1 Capacitor, 22pF, 50V, 5% NOVACAP 0805N220J500NT
AVX 08055C220JAT2A 0805 C9, C11 2
2 Capacitor, 100pF, 50V, 5% NOVACAP 0805N101J500NT
AVX 08055C101JAT2A 0805 C7, C10, C12 3
3 Capacitor, 100nF, 50V, 20% AVX 08055C104MAT2A
NOVACAP 0805B104M500 NT
SAMSUNG CL21B104MBNC 0805 C2, C8, C19, C22, C35,
C36, C37, C38 8
4 Capacitor, 4700pF, 50V, 5% CALCHIP GMC21CG472J50NT 0805
C25, C26, C27, C28 4
5 Capacitor, Tant 1µF, 16V, 20% KEMET T491A105M016AS
AVX TAJA105M016R 3216 C13 1
6 Capacitor, Tant 4.7µF, 25V KEMET T491A475M016AS
AVX TAJA475M016R 3216 C17, C20 2
7 Capacitor, 0.47µF, 50V, 5% PANASONIC ECQ-V1H474JL TH
C3, C4, C5, C6, C31,
C34 6
8 Capacitor, 0.68µF, 50V PANASONIC ECQ-V1H684JL TH
C29, C30, C32, C33 4
9 Capacitor, 2200µF, 25V, 20% PANASONIC EEU-FC1E222 TH C1, C21 2
RESISTORS
Line
Item Part Description Manufacturer & Part # Case Reference
Designators Qty
1 Resistor, 10K, 5%, 1/8W ASJ CR21J103T 0805
R1, R3, R22, R23 4
2 Resistor, 1.21K, 1%, 1/8W ASJ CR21F1211T 0805
R16, R17, R18, R19 4
3 Resistor, 49.9K, 1%, 1/8W ASJ CR21F4992T 0805
R5 1
4 Resistor, 56.2K, 1%, 1/8W ASJ CR21F5622T 0805
R2, R4 2
5 Resistor 15 Ohm, 5%, 1W KOA RM73B3A150J
ROHM MCR100JZHJ150 2512 R20, R21 2
6 Resistor, 0.01 Ohm, 1W, 5% VISHAY WSL2512R010FRE4 2512 R6, R7 2
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
Copyright © 2000
Rev. 0.1, 2004-09-30
BOARD LAYOUT
SG0341E-X1
A
U
D
I
O
M
A
X
M
i
c
r
o
s
e
m
i
C
o
r
p
.
L
X
E
1
7
2
2
S
M
R
O
U
T
+
R
O
U
T
-
V
c
c
G
N
D
L
O
U
T
-
L
O
U
T
+
INR+
INR-
R RCA IN
INL-
INL+
L RCA IN
R preout
Lpreout
AGND
O
N
-
S
l
e
e
p
-
O
F
F
O
N
-
M
u
t
e
-
O
F
F
C
l
o
c
k
C
p
w
m
R
1
7
* 1 oz copper/ea layer af ter plating
* FR-4 Material
* Green Solder Mask over Copper
* 0.062 thickness
* Tolerance for hole is +/- 0.003 Plated & unplated
* Tolerance for dimension is +/- 0.00 8 unless o t herwi se specified
4400mil
2995mil
C10
C11
C12
C
1
9
C
2
C
2
2
C25
C
2
6
C
2
7
C28
C35
C36
C37
C38
C
7
C8
C9
G1
J
1
J
2
J
P
1
J
P
3
J
P
4
J
P
5
J
P
6
JP7
L
1
L100
L
2
L
3
L
4
R1
R16
R
1
8
R19
R2
R
2
0
R
2
1
R
2
2
R23
R3
R4
R
5
R
6
R
7
U1
C
1
JP2
JP2A
C13
C
1
7
C
2
0
X1 X2
X3X4
R
C
A
1
R
C
A
2
C
3
3
C
3
2
C
3
0
C
2
9
C
3
4
C
3
1
C
3
C
4
C
6
C
5
Q
1
Q
2
Q3
Q4
C18
C
2
1
Figure 3 - Components Layer Layout
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
Copyright © 2000
Rev. 0.1, 2004-09-30
ABSOLUTE MAXIMUM RATINGS
Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C≤ TA≤ 70°C
LX1722
Parameter Symbol Test Conditions Min Typ Max
Units
Supply Voltage VCC 7 25 V
Supply Current IDD VCC=25V 6 A
Quiescent Current IQ VCC=25V, Output Open 200 mA
Sleep, Status VCC = 25V -0.3 VCC +
0.3 V
RPWM,CPWM, Mute VCC = 25V -0.3 VCC +
0.3 V
LIN+, LIN-, RIN+, RIN- VIN VCC = 25V -0.3 VCC
+0.3 V
LPREOUT, RPREOUT VPRE VCC = 25V -0.3 VCC
+0.3 V
Clock Frequency FOSC VCC = 25V 250 330 500 KHz
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
Copyright © 2000
Rev. 0.1, 2004-09-30
GRAPHS
0.001
100
0.01
0.1
1
10
50
0.9543
0.08813
%
100m 100200m 500m 1 2 5 10 20 50
65.781.037
W
dx=-64.74 W d
y
=-0.86617 %
Figure 4 – THD+N vs. Power
GRAPHS
0.001
100
0.01
0.1
1
10
50
0.32051
0.0895
%
20 20k50 100 200 500 1k 2k 5k 10k
6.325k1.00225k
Hz
dx=-5.3228 kHz d
y
=-0.23101 %
Figure 5 – THD+N vs. Frequency
PVDD=25V, F=1 KHz
10~22 KHz BPF, 4ohm
PVDD=25V, Po=1 W
10~22 KHz BPF, 4ohm
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9
Copyright © 2000
Rev. 0.1, 2004-09-30
GRAPHS
-10
+10
-8
-6
-4
-2
+0
+2
+4
+6
+8
-0.473
-1.561
d
B
r
10 80k20 50 100 200 500 1k 2k 5k 10k 20k
17.8875k18.2
Hz
dx=-17.869 kHz d
y
=-1.088 dB
Figure 6 – Frequency Response
GRAPHS
-120
+0
-100
-80
-60
-40
-20
-71.214
-1.023
d
B
r
20 20k50 100 200 500 1k 2k 5k 10k
1.96434k.973932k
Hz
dx=-.99041 kHz d
y
=+70.191 dB
Figure 7 – High Frequency Harmonic Distribution and N oise Floor
PVDD=25V, Po=1 W
10~30 KHz BPF, 4ohm
PVDD=25V, Po=1 V = 0dB
10~22 KHz BPF, 4ohm
A-weighted and no n A- weighted
LX1722SM EVALUATION BOARD USER’S GUIDE
Microsemi
Linfinity Microelectronics Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 10
Copyright © 2000
Rev. 0.1, 2004-09-30
BOARD LAYERS
Figure 8 – LX1722SM EVAL KIT Solder Mask
Figure 9 – LX1722SM EVAL KIT Silk Screen
