SANYO LA4917H

Ordering number : ENA0322
Monolithic Linear IC
LA4917H
Audio Output for TV application
High-Effciency Two-Channel 7W BTL
Power Amplifier ICs
Overview
The LA4917H is a high-effciency two-channel 7W BTL power amplifier IC. Increases in the number of external
components are held to a minimum by adopting both a signal-following type switching scheme in the amplifier’s output
stage power supply, and a nonlinear amplifier that has nonlinear characteristics in the signal system. The power dissipation
(thermal loss) in the actual operating range has been reduced to about 1/2 that of earlier class B amplifier ICs.
When used with the DIP-28H package, the IC dispenses with the heat sink and significantly contributes to space saving in
the end product case.
Features
• High-efficiency two-channel 7W BTL power amplifier IC (VCC = 12V, RL = 8Ω)
• Encapsulated in a DIP-28H package (heat sink free)
• Requires only one signal-following type switching circuit, contributing to a reduction in the number of external
components
• Provides analog outputs that generate no switching noise on the output lines
• Built-in standby switches
• Built-in protection circuits (overvoltage and thermal protection circuits)
Specifications
Maximum Ratings at Ta = 25°C
Parameter
Maximum supply voltage
Symbol
VCC max
Allowable power dissipation
Pd max
Maximum junction temperature
Tj max
Conditions
Ratings
Unit
No signal
24
V
Our recomnendation substrate
6.2
W
150
°C
Operating temperature
Topr
-25 to +75
°C
Storage temperature
Tstg
-40 to +150
°C
Operating Conditions at Ta = 25°C
Parameter
Symbol
Conditions
Ratings
Unit
Recommended supply voltage
VCC
12
V
Recommended load resistance
RL
8
Ω
Operating supply voltage range
VCC op
8 to 16
V
Any and all SANYO Semiconductor products described or contained herein do not have specifications
that can handle applications that require extremely high levels of reliability, such as life-support systems,
aircraft's control systems, or other applications whose failure can be reasonably expected to result in
serious physical and/or material damage. Consult with your SANYO Semiconductor representative
nearest you before using any SANYO Semiconductor products described or contained herein in such
applications.
SANYO Semiconductor assumes no responsibility for equipment failures that result from using products
at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition
ranges, or other parameters) listed in products specifications of any and all SANYO Semiconductor
products described or contained herein.
N1506 MS PC B8-9085 No.A0322-1/8
LA4917H
Electrical Characteristics at Ta = 25°C, VCC (Pin 21), Pre VCC (Pin 20) = 12V, RL = 8Ω, f = 1kHz, Rg = 600Ω,
See the specified board and circuit.
Parameter
Symbol
Ratings
Conditions
min
Quiescent current
ICCO
Standby current
Rg = 0, RL = Open
Ist
Unit
typ
35
max
60
120
mA
0
10
µA
31.2
dB
Amplifier off
Voltage gain
VG
VO = 0dBm
27.2
29.2
Output power
PO
THD = 10%
5
7
W
Total harmonic distortion
THD
PO = 1W, LPF = 30kHz
0.09
0.4
%
Output noise voltage
VNO
Rg = 0, DIN AUDIO*
0.05
0.3
mVrms
Ripple rejection
SVRR
Rg = 0, fR = 100Hz, VR = 0dBm, DIN AUDIO*
60
75
Channel separation
CHsep
Rg = 10kΩ, VO = 0dBm, DIN AUDIO*
50
60
21
30
Input resistance
Ri
Output offset voltage
VN offset
Standby OFF voltage
VST
Rg = 0
dB
dB
39
kΩ
mV
-120
+120
Amplifier on
2.5
16
V
Amplifier off
0
1.0
V
* : A DIN audio filter (20Hz to 20kHz) is used during measurement.
Package Dimensions
unit : mm (typ)
3233B
HEAT SPREADER
15.2
(6.2)
0.65
7.9
10.5
15
(4.9)
28
1
14
0.8
2.45max
0.3
(2.25)
2.0
Pd max -- Ta
Four-layer circuit board
(with components mounted on the back side)
6.20
6.0
5.0
Four-layer circuit board
(with no components mounted
on the back side)
4.35
Two-layer circuit board
4.0 (with components mounted
on the back side)
3.72
3.55
3.05
3.0 Two-layer circuit board
2.61
(with no components mounted
on the back side)
2.13
1.83
2.0
0
--25
0
25
50
75
100
Ambient temperature, Ta – ˚C
2.7
0.1
(0.8)
0.25
Allowable power dissipation, Pd max – W
7.0
SANYO : HSOP28H(375mil)
No.A0322-2/8
LA4917H
Block Diagram
Power supply/ground
shorting protection
circuit
PRO OUT
NC
Thermal
protection circuit
1
Output
amplifier
28
PWR GND
27
OUT 2 -
26
OUT 2 +
25
SW GND
24
SW B
23
SW E
22
SW OUT
21
V CC
20
PRE VCC
19
PH C1
18
PH C2
17
OUT 1 +
16
OUT 1 -
15
PWR GND
D
2
C
3
Ripple
filter
STB
4
Standby
switch
NC
5
NC
6
ON TIME
7
RF
Non linear
amplifier
NC
Switching
drive
H.L.S
A BCD
Switching
Regulator Block
Muting circuit
used at power on
IN 2
Output
amplifier
Amplifier
output stage
Switching
regulator block
ch2
8
9
PRE GND 10
Input
amplifier
Ref
amplifier
IN VREF 11
Output
amplifier
B
IN 1 12
NC 13
A
Input
amplifier
Non linear
amplifier
TJ MONI 14
Output
amplifier
No.A0322-3/8
LA4917H
Measurement Circuit
5V
1
PRO OUT
2
NC
PWR GND
28
OUT 2 -
27
R5
2.2 Ω
*C10
0.1µF
RL
C1
47µF
/25V
3
RF
OUT 2 +
26
VStandby
4
STB
SW GND
25
5
NC
SW B
24
NC
SW E
6
*C9
0.1µF
R4
2.2Ω
Tr1
Switching
Transistor
*R B
10Ω
23
D1
Flywheel
Di
L1
180µH
C2
22µF
/6.3V
7
ON TIME
8
IN2
SW OUT
22
V CC
21
C6
2.2µF
/25V
R1
2.2Ω
SG2
C3
2.2µF
/6.3V
9
NC
10 PRE GND
PRE V CC
20
PH C1
19
C12
1000µF
/25V
VCC
C11
1000pF
SG1
C4
2.2µF
/6.3V
11 IN VREF
12 IN1
PH C2
18
OUT 1+
17
C5
2.2µF
/6.3V
R3
2.2 Ω
*C8
0.1µF
RL
13 NC
14 TJ MONI
OUT 1-
16
PWR GND
15
*C7
0.1µF
R2
2.2 Ω
No.A0322-4/8
LA4917H
External Component Descriptions
C1 :
C2 :
This capacitor functions as a ripple filter. A value of 47µF is recommended.
This capacitor sets the amplifier startup wait time. A value of 22µF is recommended. (With this
value, the startup wait time will be about 0.7 seconds.) Although the startup wait time can be made
shorter by reducing the value of this capacitor, this can result in impulse noise appearing in the
output. We recommend always using a value larger than 10µF.
C3 and C5 :
Input capacitors. A value of 22µF is recommended. Note that if made variable, a value of 3.3µF or
lower should be used due to impulse noise considerations.
C4 :
This capacitor is the input reference amplifier capacitor, and the value must be the same as that of
C3 and C5.
C6 and R1 :
Smoothing capacitor for the switching regulator output. The LA4917H adopts a self-excited
oscillation switching regulator design. Since this capacitor influences the stability of the
self-excited oscillation, we recommend keeping the equivalent series resistance at high
frequencies low (roughly 3Ω or lower) and using a capacitor with good thermal characteristics.
For similar reasons, a value of 2.2Ω should be used for R1.
C7, C8, C9, and C10 : Oscillation prevention capacitors. We recommend using polyester film capacitors (Mylar
capacitor) with good thermal characteristics for these capacitors. These are used together with R2,
R3, R4, and R5.
C11 :
Switching regulator oscillation prevention capacitor. We recommend a value of 1000pF.
C12 :
Power supply capacitor
Tr1 and *RB :
This is an external switching transistor. Since the collector current has a peak of about 1.5A, we
recommend using a transistor in the fT = 30 to 50MHz range according to the current capacity
required. Note that if a transistor with an fT of 100MHz or higher is used, oscillation may be
induced in the switching waveform. Therefore in this case a base resistor, *RB, with a resistance of
about 10Ω must be added and the circuit adjusted so that oscillation does not occur.
L1 :
We recommend a coil inductance in the range 150 to 220µH.
D1 :
This is a flywheel diode that absorbs the coil energy. We recommend the use of a Schottky barrier
diode with a low VF.
Notes on the Switching Regulator (Pins 22 to 24)
• The LA4917H includes a signal-following self-excitation switching regulator to hold power consumption to a
minimum. The self-excitation oscillation frequency when no signal is input will be in the range from about 130 to
170kHz.
• Transistor Tr1 is an external switching transistor.
We recommend using a device with IC = 2.5A and fT = 30
to 50MHz
If a transistor with an fT of 100MHz or higher is used,
oscillation may be induced in the switching waveform.
Therefore in this case a base resistor (RB, about 10Ω) must
be added and the circuit adjusted so that oscillation does not
occur.
• C6 is used to smooth the output of the switching regulator.
Since this capacitor influences the stability of the
self-excited oscillation, we recommend keeping the
equivalent series resistance at high frequencies low and
using a capacitor with good thermal characteristics. The
recommended value for this capacitor is 2.2µF.
Note that for similar reasons, a resistor with a value of 2.2Ω
should be used for R1.
24
SW B
*RB
10Ω
Tr1
Switching
Transistor
I C =2.5A
f T = 30 to 50MHz
23
SW E
22
SW OUT
D1
Flywheel
Diode
L1
180µH
C6
2.2µF
/25V
R1
2.2 Ω
• D1 is a flywheel diode that absorbs the coil energy. We
recommend the use of a Schottky barrier diode with a low
VF.
No.A0322-5/8
LA4917H
Notes on the Standby Function (STB, pin 4)
The amplifier is turned on by applying a level of 2.5V
(minimum) or higher to pin 4.
Pin 4 control voltage
Voltage applied to pin 4 (V)
Amplifier
Standby
0 to 1.0
Off
On
2.5 to 16
On
Off
2VBE
VST
RSTB
4
The limit resistor RSTB may be inserted if the VST applied
voltage is comparatively high and there is a need to suppress
the pin 4 sink current.
10k Ω
10kΩ
30kΩ
Example : When it is necessary to limit the pin 4 sink current
to under 500µA.
RSTB =
VST-2VBE (about 1.4V)
-10kΩ
500µA
Notes on the Self Diagnostics Function (PRO OUT, pin 1)
The self diagnostics function detects when a power amplifier
output pin has been shorted to VCC or ground and reports that
state to external circuits.
In the example shown at the right, during normal operation
this output will be at the high level, but if the protection
circuit operates, an internal transistor will be turned on and
the pin will go to the low level (about 0.2 to 0.3V).
Note that this circuit has an npn transistor open-collector
output.
* : This pin is left open when this function is not used.
+5V
RPRO
1
1k Ω
Output short
protection circuit
Notes on the TJ MONI Function (pin 14)
The pin 14 internal circuit has diodes (three diodes connected in series) connected to ground as shown in the circuit
diagram figure. These diodes' forward voltage has the temperature dependence shown in the figure at the lower left.
The IC's internal junction temperature can be inferred using these characteristics.
V14 -- Tj (Reference value)
Pin 14 voltage, V14 – V
2.5
2
1.5
Tj Monitor
14
1k Ω
1
0.5
0
0
50
100
150
200
Junction temperature, Tj – ˚C
No.A0322-6/8
LA4917H
Circuit Board Specifications (LA4917H recommended circuit boards)
1) Four-layer circuit board (2S2P)
Board size : 90×90×1.6mm (glass epoxy)
Copper wiring densities : L1 = 60%, L2 = 90%, L3 = 90%, and L4 = 90% (LA4917H mounting surface)
2) Two-layer board (2SOP)
Board size : 90×90×1.6mm (glass epoxy)
Copper wiring densities : L1 = 60% and L2 = 90% (LA4917H mounting surface)
L1 : Copper wiring pattern diagram
L4 (four-layer circuit board),
L2 (two-layer circuit board) :
Copper wiring pattern diagram
Notes
1. The data for the back surface solder mounting case applies when 80% or more of the heat sink surface is wetted.
2. End products must be designed with enough derating to provide adequate margins.
The stresses for which derating must be applied are as follows : voltage, current, junction temperature, power loss and
mechanical stresses such as vibration and shock. Therefore end products must also be designed to keep these stresses as
low or as small as possible.
We present some common derating standards below.
(1) For voltage ratings, 80% or less of the maximum value
(2) For current ratings, 80% or less of the maximum value
(3) For temperature ratings, 80% or less of the maximum value
3. In product design, full testing must be performed in an actual end product.
Furthermore, not only must the solder joint states of heat sinks and heat dissipation fins be checked carefully, but
thorough reliability testing of all solder joints must also be performed. If voids or degradation of the solder joints in
these areas are found, the thermal conductivity with the circuit board will be degraded and this can lead to thermal
destruction of the IC. In such cases, reanalyze the usage conditions, look into optimizing circuit board land dimensions,
masks, and printing conditions, and use a solder with superlative thermal stress resistance.
No.A0322-7/8
LA4917H
Usage Notes
1. This IC includes power supply shorting (shorting between the power supply and the outputs) and ground shorting
(shorting between ground and the outputs) protection circuits. These circuits operate to protect the IC against abnormal
connections.
These circuits will continue to operate as long as the corresponding abnormal condition continues and recover
automatically when the abnormal condition is cleared.
2. This IC includes a thermal protection circuit that operates when the junction temperature (Tj) exceeds about 160°C.
This circuit gradually lowers (attenuates) the outputs.
3. If this IC is operated in the vicinity of its maximum ratings, small fluctuations in the operating conditions may cause
the maximum ratings to be exceeded and may lead to destruction of the IC. Therefore, designs must provide adequate
margins in the supply voltage and other parameters so that this IC will only be used within ranges such that the
maximum ratings are never exceeded.
Specifications of any and all SANYO Semiconductor products described or contained herein stipulate the
performance, characteristics, and functions of the described products in the independent state, and are
not guarantees of the performance, characteristics, and functions of the described products as mounted
in the customer's products or equipment. To verify symptoms and states that cannot be evaluated in an
independent device, the customer should always evaluate and test devices mounted in the customer's
products or equipment.
SANYO Semiconductor Co., Ltd. strives to supply high-quality high-reliability products. However, any
and all semiconductor products fail with some probability. It is possible that these probabilistic failures
could give rise to accidents or events that could endanger human lives, that could give rise to smoke or
fire, or that could cause damage to other property. When designing equipment, adopt safety measures
so that these kinds of accidents or events cannot occur. Such measures include but are not limited to
protective circuits and error prevention circuits for safe design, redundant design, and structural design.
In the event that any or all SANYO Semiconductor products (including technical data,services) described
or contained herein are controlled under any of applicable local export control laws and regulations, such
products must not be exported without obtaining the export license from the authorities concerned in
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mechanical, including photocopying and recording, or any information storage or retrieval system, or
otherwise, without the prior written permission of SANYO Semiconductor Co., Ltd.
Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification"
for the SANYO Semiconductor product that you intend to use.
Information (including circuit diagrams and circuit parameters) herein is for example only; it is not
guaranteed for volume production. SANYO Semiconductor believes information herein is accurate and
reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual
property rights or other rights of third parties.
This catalog provides information as of November, 2006. Specifications and information herein are subject
to change without notice.
PS No.A0322-8/8