NJRC NJU8719

NJU8719
PRELIMINARY
Monaural BTL Output Switching Driver for Class D Amplifier
! PACKAGE OUTLINE
! 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
! PIN CONFIGURATION
! 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
VDD
IN
NC
MCK
STBYB
10
9
8
7
6
1
2
3
4
5
VSS
OUTP
VDDO
OUTN
VSS
! BLOCK DIAGRAM
VDD
VDDO VSS
IN
OUTP
Dead Time
Generator
MCK
OUTN
STBYB
Ver.2004-05-20
VSS
-1-
NJU8719
! TERMINAL DESCRIPTION
No.
1
2
3
SYMBOL
VDD
IN
NC
I/O
−
I
−
4
MCK
I
Function
Power Supply, VDD=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: VSS=0V
VSS
−
10
7
OUTN
O
Negative output
8
VDDO
−
Output Power Supply, VDD=5V
9
OUTP
O
Positive output
*VSS(Terminal No.6,10) should be connected at a nearest point to the IC.
*VDD(Terminal No.1) and VDDO(Terminal No.8) should be connected at a nearest point to the IC.
*STBYB(Terminal No.5) must be connected to VDD, when this terminal is not used.
! INPUT TERMINAL STRUCTURE
VDD
Input
Terminal
VSS
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2 --
Ver.2004-05-20
NJU8719
NJU3555
! FUNCTIONAL DESCRIPTION
(1) Signal Output
The OUTP and OUTN 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 OUTP is a positive output and OUTN
is a negative outputs.
A switching regulator with a high response against a voltage fluctuation is the best selection for the VDDO,
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.
OUTP and OUTN 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.
OUTP and OUTN 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
SYMBOL
VDD
VDDO
RATING
-0.3 to +5.5
-0.3 to +5.5
UNIT
Input Voltage
Vin
-0.3 to VDD+0.3
V
Operating Temperature
Topr
-40 to +85
°C
Storage Temperature
Tstg
-40 to +125
°C
PD
360*
mW
Supply Voltage
Power Dissipation
SSOP10
V
* : Mounted on two-layer board of based on the JEDEC.
Note 1) All voltage values are specified as VSS=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 VDD-VSS and VDDO-VSS due to the stabilized
operation.
! ELECTRICAL CHARACTERISTICS
(Ta=25°C, VDD= VDDO=5.0V, VSS=0V, fS=44.1kHz, unless otherwise noted)
PARAMETER
SYMBOL
CONDITIONS
MIN.
TYP.
MAX.
UNIT
2.4
5.0
5.25
V
VDD ,VDDO
Supply Voltage
VDD
Output Driver
High side Resistance
RH
VOUT=VDDO-0.1V
-
0.5
1.5
Ω
Output Driver
Low side Resistance
RL
VOUT=0.1V
-
0.5
1.5
Ω
-
-
1
µA
-
3.8
5.7
mA
VIH
0.7VDD
-
VDD
V
VIL
0
-
0.3VDD
V
ILK
-
-
±1
µA
Operating Current
at Standby
Operating Current
at Operating
(Mute signal input)
IST
IDD
IN, STBYB=0V
No-load operating
IN=32fS
MCK=256fS
No-load operating
Input Voltage
Input Leakage Current
-- 4
4 --
Ver.2004-05-20
NJU8719
NJU3555
! TIMING CHARACTERISTICS
•
Audio Signal Input
tMCKL
tMCKH
MCK
IN
tDS
(Ta=25°C, VDD= VDDO=5.0V, VSS=0V, fS=44.1kHz, unless otherwise noted)
SYMBOL
CONDITIONS
MIN.
TYP.
MAX.
UNIT
PARAMETER
•
tDH
MCK Frequency
fMCKI
-
-
25
MHz
MCK Pulse Width (H)
tMCKH
12
-
-
ns
MCK Pulse Width (L)
tMCKL
12
-
-
ns
IN Setup Time
tDS
20
-
-
ns
IN Hold Time
tDH
20
-
-
ns
Output Control Signal Input
STBYB
0.7VDD
0.7VDD
0.3VDD
0.3VDD
tUP
PARAMETER
tDN
(Ta=25°C, VDD= VDDO=5.0V, VSS=0V, fS=44.1kHz, unless otherwise noted)
SYMBOL
CONDITIONS
MIN.
TYP.
MAX.
UNIT
Rise Time
tUP
-
-
50
ns
Fall Time
tDN
-
-
50
ns
Note 4) All timings are based on 30% and 70% voltage level of VDD.
Ver.2004-05-20
-5-
NJU8719
! APPLICATION CIRCUIT
22µH
VDD
10µF 0.1µF
OUTP(9)
VDD(1)
1µF
VSS(10)
IN(2)
MCK(4)
STBYB(5)
NJU8719
8Ω
22µH
OUTN(7)
VDDO(8)
1µF
100µF
1µF
Speaker
VDDO
VSS(6)
Note 5) De-coupling capacitors must be connected between each power supply terminal and GND terminal.
Note 6) The power supply for VDDO requires fast driving response performance such as a switching regulator
for T.H.D..
Note 7) The above circuit shows only application example and does not guarantee the any electrical
characteristics. Therefore, please consider and check the circuit carefully to fit your application.
[CAUTION]
The specifications on this databook are only
given for information , without any guarantee
as regards either mistakes or omissions. The
application circuits in this databook are
described only to show representative usages
of the product and not intended for the
guarantee or permission of any right including
the industrial rights.
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Ver.2004-05-20