LX1710 Microsemi Corporation, LX1710 Datasheet - Page 5

• Manufacturer Part Number: LX1710
• Description: Class-D Mono Power Amplifier Controller IC
• Manufacturer: Microsemi Corporation

Copyright
Rev. 1.1, 2000-12-01
Frequency Synchronization
A
Two or more LX1710 / LX1711 oscillators can be configured for
synchronous operation. One unit, the master, is programmed for
the desired frequency with the R
Additional units will be slave units, and their oscillators will be
disabled by leaving the R
and the C
pin and the C
configuration, the CLOCK pins of the slave units begin receiving
instead of transmitting clock pulses. Also, the C
driving the PWM capacitor in the slave units. Note that for
optimum performance, all slave units should be located within a
few inches of the master unit.
M I C R O S E M I
IN A M P O U T
2000
PWM
IN P U T +
IN P U T -
C LO C K
E A O UT
R P W M
C P W M
M UT E
E A IN
V D D
IS -
pin of the slave units should be tied to the CLOCK
PWM



pin of the master unit respectively. In this
25
27
28
14
13
11
5
6
9
8
7

PWM
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
pin disconnected. The CLOCK pin
C O M P A N Y
PWM
IN P U T A M P
S Y N C
E R R O R A M P
O S C
and C
          
               
LX1710/11 S IM P LIFIE D B LO C K D IA G R A M
PWM
PWM

C LK
Linfinity Microelectronics Division
M U T E
M U T E
as usual.
pins quit
   
     
   
     


M UX
Microsemi
P V D D
C U RR E N T S E N S E
- LX1710 Block Diagram
+
-
220m V
Class-D Mono Power Amplifier Controller IC
Oscillator Configuration (R
AudioMAX™
The oscillator is programmed by the external timing components R
and C
should be set to 49.9kOhms and 100pF respectively. Note that in order
to keep the slope of the PWM ramp voltage proportional to the supply
voltage, both the ramp peak and valley voltages, and the charge and
discharge currents are proportional to the supply voltage. This keeps
the frequency relatively constant while keeping the slope of the PWM
ramp proportional to the voltage on the VDD pin. For operating
frequencies other than 333kHz, the frequency can be approximated by
the following equation:
    
PWM
Frequency
. For a nominal frequency of 333kHz, R
R E F E R E N C E
C LK
U V LO
&
F A U LT
T IM E R
S
R
F E E D B A C K A M P
Q
Q
P
(
. 0
RELIMINARY
577
PWM
D R IV E R S
O U T P U T
LO G IC
)(
R eference
R eference
and C
&
R
5V
5V
PWM
PWM
)(
1
C
selection)
PWM
LX1710/1711
18
10
24
26
23
22
21
20
15
17
16
1
4
)
F A O U T
S LE E P
V R E F
F B K +
F B K -
V 25
P V D D
N +
C P
P +
N -
P -
C N
PWM
320
and C
ns
PWM
PWM
Page 5