NJU8719
PRELIMINARY
Monaural BTL Output Switching Driver for Class D Amplifier
!
GENERAL DESCRIPTION
The
NJU8719
is a monaural BTL output switching driver
for class D amplifier. It converts 1bit digital signal input,
such as PWM or PDM signal, to analog signal output with
simple external LC low-pass filter.
The
NJU8719
realizes very high power-efficiency by
class D operation. Therefore, It is suitable for portable
set with speaker.
NJU8719V
!
PACKAGE OUTLINE
!
FEATURES
#
#
#
#
#
#
1-channel 1bit Audio Signal Input
Monaural BTL Output
Standby(Hi-Z) Control Function
Operating Voltage : 2.4V to 5.25V
CMOS Technology
Package Outline
: SSOP10
!
PIN CONFIGURATION
V
DD
IN
NC
MCK
STBYB
1
2
3
4
5
10
9
8
7
6
V
SS
OUT
P
V
DDO
OUT
N
V
SS
!
BLOCK DIAGRAM
V
DD
V
DDO
V
SS
IN
Dead Time
Generator
MCK
OUT
P
OUT
N
STBYB
V
SS
Ver.2004-05-20
-1-
NJU8719
!
TERMINAL DESCRIPTION
No.
1
2
3
4
SYMBOL
V
DD
IN
NC
MCK
I/O
−
I
−
I
Function
Power Supply, V
DD
=5V
1-bit Data Input Terminal
Non connection
Master Clock Input Terminal
The condition of the data input terminal is fetched with the rising
edge of this signal.
Standby Control Terminal (L:Standby)
5
STBYB
I
6
Power GND and Output GND terminal: V
SS
=0V
V
SS
−
10
7
OUT
N
O
Negative output
8
V
DDO
−
Output Power Supply, V
DD
=5V
9
OUT
P
O
Positive output
*V
SS
(Terminal No.6,10) should be connected at a nearest point to the IC.
*V
DD
(Terminal No.1) and V
DDO
(Terminal No.8) should be connected at a nearest point to the IC.
*STBYB(Terminal No.5) must be connected to V
DD
, when this terminal is not used.
!
INPUT TERMINAL STRUCTURE
V
DD
Input
Terminal
V
SS
-2-
-2-
Ver.2004-05-20
NJU8719
NJU3555
!
FUNCTIONAL DESCRIPTION
(1) Signal Output
The OUT
P
and OUT
N
generate PMW output signal, which is converted to analog signal via external 2nd-order
or higher LC filter. The NJU8719 drives a speaker by the BTL output, and OUT
P
is a positive output and OUT
N
is a negative outputs.
A switching regulator with a high response against a voltage fluctuation is the best selection for the V
DDO,
which is the power supply for output drivers. To obtain better T.H.D. performance, the stabilization of the power
is required.
(2) Standby Control Function
By setting the STBYB terminal to “L”, the
NJU8719
becomes standby condition.
OUT
P
and OUT
N
are in Hi-Z.
During standby condition,
(3) Master Clock
Master clock (MCK) synchronizes with the Audio signal input (IN). The setup time and the hold time should
be kept in the AC characteristics because IN is fetched with the rising edge of MCK. MCK requires jitter-free or
jitter as small as possible because the jitter downs S/N ratio.
OUT
P
and OUT
N
occur the pop noise when MCK is stopped in operation without standby mode. Therefore,
the standby mode should be set before MCK stop.
Ver.2004-05-20
-3-
NJU8719
!
ABSOLUTE MAXIMUM RATINGS
(Ta=25°C)
PARAMETER
Supply Voltage
Input Voltage
Operating Temperature
Storage Temperature
Power Dissipation
SSOP10
SYMBOL
V
DD
V
DDO
Vin
Topr
Tstg
P
D
RATING
-0.3 to +5.5
-0.3 to +5.5
-0.3 to V
DD
+0.3
-40 to +85
-40 to +125
360*
UNIT
V
V
°C
°C
mW
* : Mounted on two-layer board of based on the JEDEC.
Note 1) All voltage values are specified as V
SS
=0V.
Note 2) If the LSI is used on condition beyond the absolute maximum rating, the LSI may be destroyed.
Using LSI within electrical characteristics is strongly recommended for normal operation. Use beyond
the electrical characteristics conditions will cause malfunction and poor reliability.
Note 3) De-coupling capacitors should be connected between V
DD
-V
SS
and V
DDO
-V
SS
due to the stabilized
operation.
!
ELECTRICAL CHARACTERISTICS
(Ta=25°C, V
DD
= V
DDO
=5.0V, V
SS
=0V, f
S
=44.1kHz, unless otherwise noted)
PARAMETER
V
DD
,V
DDO
Supply Voltage
Output Driver
High side Resistance
Output Driver
Low side Resistance
Operating Current
at Standby
Operating Current
at Operating
(Mute signal input)
Input Voltage
V
IL
Input Leakage Current
I
LK
0
-
-
-
0.3V
DD
±1
V
µA
SYMBOL
V
DD
R
H
R
L
I
ST
I
DD
V
IH
V
OUT
=V
DDO
-0.1V
V
OUT
=0.1V
IN, STBYB=0V
No-load operating
IN=32f
S
MCK=256f
S
No-load operating
CONDITIONS
MIN.
2.4
-
-
-
-
0.7V
DD
TYP.
5.0
0.5
0.5
-
3.8
-
MAX.
5.25
1.5
1.5
1
5.7
V
DD
UNIT
V
Ω
Ω
µA
mA
V
-4-
-4-
Ver.2004-05-20
NJU8719
NJU3555
!
TIMING CHARACTERISTICS
•
Audio Signal Input
t
MCKH
MCK
t
MCKL
IN
t
DS
t
DH
PARAMETER
MCK Frequency
MCK Pulse Width (H)
MCK Pulse Width (L)
IN Setup Time
IN Hold Time
(Ta=25°C, V
DD
= V
DDO
=5.0V, V
SS
=0V, f
S
=44.1kHz, unless otherwise noted)
SYMBOL
CONDITIONS
MIN.
TYP.
MAX.
UNIT
f
MCKI
t
MCKH
t
MCKL
t
DS
t
DH
-
12
12
20
20
-
-
-
-
-
25
-
-
-
-
MHz
ns
ns
ns
ns
•
Output Control Signal Input
0.7V
DD
0.3V
DD
0.7V
DD
0.3V
DD
STBYB
t
UP
t
DN
PARAMETER
Rise Time
Fall Time
(Ta=25°C, V
DD
= V
DDO
=5.0V, V
SS
=0V, f
S
=44.1kHz, unless otherwise noted)
SYMBOL
CONDITIONS
MIN.
TYP.
MAX.
UNIT
t
UP
t
DN
-
-
-
-
50
50
ns
ns
Note 4) All timings are based on 30% and 70% voltage level of V
DD
.
Ver.2004-05-20
-5-
Microchip MCU
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