Document
Ordering number : ENN7043
Monolithic Linear IC
LA4742
45 W Four-Channel (Bridge Circuit) Power Amplifier
Overview
The LA4742 is a 45 W 4-channel power amplifier IC for car stereo systems. It features a built-in bridge circuit and the ability to radically reduce the number of external components required.
Package Dimensions
unit: mm 3236-HZIP25
[LA4742]
29.2 25.6 4.5
Features
• Maximum output power: 45 W × 4 channels (VCC = 14.4 V, 4 Ω load, 1 kHz) • 40 W × 4 channels (VCC = 13.7 V, 4 Ω load, 1 kHz) • Requires only seven external components and does not require an oscillation prevention RC circuit, a noise filter, or a BS capacitor.
R1.7 14.4 17.4 3.3 10.2
0.4 4.0 4.0
Functions
• Output offset detection function (DDL) • Warning tone (beep) generation function • Muting function • Built-in standby switch • Full complement of built-in protection circuits, including protection from shorting to VCC, shorting to ground, load shorting, overvoltages, and overheating. • Maximum supply voltage before damage in the open ground state: 16 V
2.60 2.0
(1.0) 2.0
0.53
SANYO: HZIP25
Specifications
Maximum Ratings at Ta = 25°C
Parameter Maximum supply voltage Maximum output current Allowable power dissipation Operating temperature Storage temperature Package thermal resistance Symbol VCC max1 VCC max2 IOpeak Pd max Topr Tstg θjc With an arbitrarily large heat sink Signal present No signal (for 1 minute) Conditions Ratings 18 26 4.5/ch 50 –40 to +85 –40 to +150 1 Unit V V A W °C °C °C/W
Any and all SANYO 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 representative nearest you before using any SANYO products described or contained herein in such applications. SANYO 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 products described or contained herein.
SANYO Electric Co.,Ltd. Semiconductor Company
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN
92101TN (OT) No. 7043-1/9
LA4742 Operating Conditions at Ta = 25°C
Parameter Recommended supply voltage Recommended load resistance Operating supply voltage range Symbol VCC RL VCC op Conditions Ratings 14.4 4 9 to 18 Unit V Ω V
Operating Characteristics at Ta = 25°C, VCC = 14.4 V, f = 1 kHz, RL = 4 Ω, Rg = 600 Ω
Parameter Quiescent current Standby current Output offset voltage Voltage gain Voltage gain difference Symbol ICCO Ist VNoffset VG ∆VG PO1 Output power PO max1 PO max2 Total harmonic distortion Channel separation Ripple rejection ratio Output noise voltage Muting attenuation THD CHsep SVRR VNO Mute(att) THD = 10 % VCC = 13.7 V, VIN = 5 Vrms VIN = 5 Vrms PO = 4 W VO = 0 dBm, Rg = 10 kΩ fr = 100 Hz, VR = 0 dBm, Rg = 0 Rg = 0, B.P.F. = 20 Hz to 20 kHz VO = 20 dBm 70 55 50 RL = ∞, Rg = 0 Vst = 0 V Rg = 0 VO = 0 dBm –100 25 –1 23 28 40 45 0.05 65 60 100 80 200 0.4 26 Conditions Ratings min 100 typ 200 max 350 10 +100 27 +1 Unit mA µA mV dB dB W W W % dB dB µVrms dB
No. 7043-2/9
LA4742 Sample Application Circuit and Block Diagram
2200µF VCC1/2 6 IN 1 + 11 + 20 + 9 VCC3/4
+
0.022µF
OUT 1+
0.22µF
+5V
10kΩ
25
Clip Detect Circuit
–
–
7
OUT 1– PWR GND 1
CLIP DET Protective Circuit 8
– IN 2
+
5
OUT 2+
+
12
+
–
3
0.22µF Aux Circuit ST BY 4 +5V ST ON R.F 47µF IN 3 + 15 0.22µF AUX IN + 1 – + 17 + 10 Stand by Switch Ripple Filter Mute Circuit 2
OUT 2– PWR GND 2
Mute 22 3.3µF OUT 3+ +
10kΩ
Low Level Mute ON
+
–
19
0.22µF PRE GND 13 Protective Circuit 18
OUT 3– PWR GND 3
– IN 4 + 14 0.22µF ON TIME C 16 + 22µF Muting & ON Time Control Circuit
+
21
OUT 4+
+
–
23
OUT 4– PWR GND 4
24
Top view
A13765
No. 7043-3/9
LA4742 Pin Functions and Equivalent Circuits at VCC = 14.4 V, ST-BY = 5 V
Pin No. 1 2 8 18 24
VCC 130 Ω
Function AUX IN
DC voltage [V]
Notes
Internal equivalent circuit
POWER GND
3 5 7 9 17 19 21 23
–OUT2 +OUT2 –OUT1 +OUT1 +OUT3 –OUT3 +OUT4 –OUT4
130 Ω Lowsaturation voltage circuit 3 5 7 9 17 19 21 23
A13766
2.7
10 kΩ 4
4
ST-BY
• The amplifier will be on when the applied voltage is between 2 V and VCC.
30 kΩ
1.5 kΩ
A13767
6 20
VCC1/2 VCC3/4
Bias circuit ST-BY power supply line
Input amplifier ST-BY power supply line
10
SVR
13.2
• Low ripple power supply line for all internal IC blocks
VCC
200 Ω
200 Ω 1 kΩ
10
A13768
Continued on next page.
No. 7043-4/9
LA4742
Continued from preceding page.
Pin No. Function DC voltage [V] Notes
Input amplifier ST-BY power supply line
Internal equivalent circuit
5 pF
11 12 14 15
IN1 IN2 IN4 IN3
11 12 14 15 VREF
30 kΩ
1 kΩ
3.1
.