Ordering number: EN3680C Monolithic Linear IC LA4485 5 W, Two-channel Power Amplifier with Very Few External Parts Overview Package Dimensions The LA4485 is a 5 W, two-channel power amplifier IC that requires a minimum of external parts, making it ideal for radio cassette players and car stereo equipment. unit : mm 3107-SIP13H [LA4485] The LA4485 eliminates the need for bootstrap capacitors, negative feedback capacitors, and oscillation prevention CR parts, all of which were necessities for power ICs previously. All of these functions are now on chip, keeping the number of external parts to an absolute minimum. The LA4485 is part of the Power (Stylish Power) Series, and supports two modes: dual and BTL. Features . 5 W × 2 output power in dual mode, and 15 W in BTL mode . Minimum external parts for the Power Series count: or 5 parts in dual mode; 3 or 4 parts in BTL mode . 4Protection circuits . . . . SANYO : SIP13H Overvoltage protection Thermal protection DC output short-circuit protection (to VCC and to GND) Circuitry designed to handle +VCC applied to the outputs Pop noise reduction Standby switch Muting function Specifications Maximum Ratings at Ta = 25°C Parameter Maximum supply voltage Surge supply voltage Symbol VCC max VCC surge * Conditions Ratings Unit No signal 24 V Based on the JASO standard 50 V Peak output current IO peak Per channel 3.3 A Allowable power dissipation Pd max With infinite heat sink 15 W Operating temperature Topr –30 to +80 °C Storage temperature Tstg –40 to +150 °C Ratings Unit *: By the π type B check point method. Operating Conditions at Ta = 25°C Parameter Recommended supply voltage Supply voltage range Recommended load resistance range Symbol Conditions VCC VCC op RL 13.2 Must not be over package Pd V 7.5 to 18 V Dual 2 to 8 Ω BTL 4 to 8 Ω SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN 73096HA(II)/D2893TS/9041TS No.3680-1/20 LA4485 Operating Characteristics at Ta = 25°C, VCC = 13.2 V, RL = 4 Ω, Rg = 600 Ω, f = 1 kHz, Dual Parameter Standby current Quiescent supply current Symbol Ist ICCO VG1 VG2 PO1* P O2 THD CH sep VNO Voltage gain Output power Total harmonic distortion Channel separation Output noise voltage Ripple rejection ratio Conditions Pin 9 to GND, Standby switch OFF Rg = 0 Dual: VO = 0 dBm BTL: VO = 0 dBm Dual: THD = 10% BTL: THD = 10% PO = 1 W VO = 0 dBm, Rg = 0 Rg = 0, 20 Hz to 20 kHz bandpass filter Rg = 0, 20 Hz to 20 kHz bandpass filter, fR = 100 Hz, VR = 0 dBm, decoupling capacitor connected SVRR min typ 40 43 80 45 51 5 15 0.15 55 0.15 4 11 45 40 50 max 10 160 47 0.8 0.5 Unit µA mA dB dB W W % dB mV dB Allowable power dissipation, Pd max – W *: PO1 = 6 W (typ) when VCC = 14.4 V Voff ± 250 mV for BTL-mode Pd max – Ta Al heat sink mounting conditions Mounting torque 39 Nvcm. Flat washer with silicone grease applied Infinite heat sink No heat sink Ambient temperature, Ta – °C Equivalent Circuit Block Diagram FILTER Large signal VCC Small signal VCC Filter CH1 IN Input amp CH1 Pre drive amp Output-to-ground short-circuit protection Output amp CH1 OUT Output-to-supply short-circuit protection Thermal shutdown protection Small signal GND REF amp Large signal GND Overvoltage protection BTL IN CH2 IN Input amp CH2 Pre drive amp Output-to-supply short-circuit protection Output amp Standby switch BTL OUT CH2 OUT Output-to-ground short-circuit protection STANDBY Mute MUTE No.3680-2/20 LA4485 Recommended LA4485 External Parts Arrangement (Dual-mode) 95.0 × 67.0 mm2 IC Usage Notes Maximum ratings Care must be taken when operating the LA4485 close to the maximum ratings as small changes in the operating conditions can cause the maximum ratings to be exceeded, thereby breakdown will be caused. Printed circuit board connections Care must be taken when designing the circuit of printed board so as not to form feedback loops, particularly with the small-signal and large-signal ground connections. Notes on LA4485 heatsink mounting 1. 2. 3. 4. 5. 6. Mounting torque must be in the range 39 to 59 Nvcm. The spacing of the tapped holes in the heatsink must match the spacing of the holes in the IC tab. Use screws with heads equivalent to truss head machine screws and binding head machine screws stipulated by JIS for the mounting screws. Furthermore, washers must be used to protect the surface of the IC tab. Make sure that there is no foreign matter, such as cutting debris, between the IC tab and the heatsink. If a heat conducting compound is applied between the contact surfaces, make sure that it is spread uniformly over the entire surface. Because the heatsink mounting tab and the heatsink are at the same electric potential as the chip’s GND (large signal GND), care must be taken when mounting the heatsink on more than one device. The heatsink must be mounted before soldering the pins to the PCB. Comparison of External Parts Required Existing device LA4485 Output coupling capacitors External parts Yes Yes Input coupling capacitors Yes Yes Bootstrap capacitors Yes No Feedback capacitors Yes No Filter capacitor Yes Optional Phase compensating capacitor Yes No Oscillation-quenching mylar capacitors Yes No Oscillation-quenching resistors Yes No Others No Optional 15 to 16 parts 4 to 6 parts Total (for dual-mode) Note: Supply capacitors, contained within the power IC, are not counted in both existing and new devices. No.3680-3/20 LA4485 Operating Pin Voltages at VCC = 13.2 V Pin No. Name Function Pin voltage (Reference value) 1 CH1 IN Channel 1 input. 1.4 V (2 VBE) 2 CH2 IN Channel 2 input. 1.4 V (2 VBE) 3 SS GND Small-signal ground 0V 4 BTL IN BTL-mode feedback input. 45 mV 5 BTL OUT BTL-mode feedback output. 3.1 V (61/4 VCC) 6 FILTER Filter capacitor connection. 6.6 V (61/2 VCC) 7 LS VCC Large-signal supply 13.2 V (VCC) 8 SS VCC Small-signal supply 13.2 V (VCC) 9 STANDBY Standby control input. 5V 10 MUTE Mute control input. 0V 11 CH2 OUT Channel 2 output. 6.3 V 12 LS GND Large-signal ground 0V 13 CH1 OUT Channel 1 output. 6.3 V Note: Each pin is so arranged lest the IC should be broken even if inserted reversely. LA4485 Sample Application Circuit No.3680-4/20 LA4485 VN – VCC ICCO – VCC Output pin voltage, VN – V Rg = 0 standby + 5 V Overvoltage cutoff VCC = 7.5 V Cutoff for waveform carrying signal Muting on Supply voltage, VCC – V lst – VCC ICCO Muting on Supply voltage, VCC – V PO – VIN CVCC = 0.15 µF (mylar) Rg = 0 Standby to GND Output power, PO – W Standby current, Ist – µA RL = 4 Ω Rg = 0 Quiescent supply current, ICCO – mA RL = 4 Ω (dual) Input voltage, VIN – mV THD – f Total harmonic distortion, THD – % Total harmonic distortion, THD – % Supply voltage, VCC – V THD – PO VCC = 13.2 V RL = 4 Ω f = 1 kHz Rg = 600 Ω Frequency, f – Hz THD – VCC Response – dB Total harmonic distortion, THD – % Output power, PO – W f Response Frequency, f – Hz Supply voltage, VCC – V No.3680-5/20 LA4485 PO – VCC ICC – PO Current drain, ICC (2CH) – A Output power, PO – W Supply voltage, VCC – V Output power, PO (1CH) – W Pd – PO Dual RL = 2 Ω Dual RL = 3 Ω Power dissipation, Pd (2CH) – W Power dissipation, Pd (2CH) – W Pd – PO Output power, PO (1CH) – W Pd – PO Dual RL = 8 Ω Output power, PO (1CH) – W Allowable power dissipation, Pd max (2CH) –W Power dissipation, Pd (2CH) – W Dual RL = 4 Ω Output power, PO (1CH) – W Pd – PO Dual RL = 6 Ω Power dissipation, Pd (2CH) – W Output power, PO (1CH) – W Pd – PO Power dissipation, Pd (2CH) – W Dual Rg = 600 Ω f = 1 kHz Output power, PO (1CH) – W Pd max – VCC Dual Ta = 25°C Supply voltage, VCC – V No.3680-6/20 LA4485 Leakage from CH1 to CH2 SVRR – VR Ripple rejection ratio, SVRR – dB Leakage from CH2 to CH1 Supply ripple voltage, VR – mV SVRR – VCC SVRR – fR Ripple rejection ratio, SVRR – dB Frequency, f – Hz Ripple rejection ratio, SVRR – dB Channel separation, CH sep – dB CH sep – f Ripple frequency, fR – Hz ICCO – Ta VN – Ta Output pin voltage, VN – V Quiescent current, ICCO – mA Supply voltage, VCC – V Temperature characteristic due to output capacitor CO = 1000 µF Ambient temperature, Ta – °C Ambient temperature, Ta – °C VNO – Rg Output noise voltage, VNO – mV Output power, PO – W Ambient temperature, Ta – °C PO – Ta VCC = 13.2 V RL = 4 Ω BPF = 20 Hz to 20 kHz Rg = 0 → 0.12 mV Source resistance, Rg – Ω No.3680-7/20 LA4485 Output DC trace Speaker terminal VCC = 13.2 V, standby supply +5 V, RL = 4 Ω, Rg = 0 Main switch ON/OFF test Output DC trace Speaker terminal VCC = 13.2 V, standby supply +5 V, RL = 4 Ω, Rg = 0 Standby switch ON/OFF text VCC = 13.2 V, RL = 4 Ω, Rg = 0, Mute ON/OFF → Switching noise decreases as CIN = 0.22 µF (Input) is increased. (ex. 2.2 µF) VCC = 13.2 V, RL = 4 Ω, Rg = 600 Ω, THD = 10%, f = 1 kHz, Output DC waveform No.3680-8/20 LA4485 Dual-mode Operation Notes . Use the input capacitor C IN in the range of 0.22 µF to 1.0 µF. Parameter CIN = 0.22 µF CIN = 1.0 µF 0.15 s 0.25 s Somewhat noticeable Good Start-up time (ts) Attack noise when using the muting function Speaker turn-ON transient noise increased significantly when CIN is 2.2 µF or greater. . The DC (filter) capacitor should be 100 µF or greater. Parameter 100 µF or less 100 µF or more Standby-off output capacitor discharge circuit *1. Does not operate. Repeated on/off: poor *2. Operates normally. On/off: good Ripple rejection ratio (SVRR) Somewhat worse 40 dB Good 50 dB Fast Slow VN rise rate when main or standby is turned ‘‘on’’ Note: *1. Slow as a result of natural discharge. *2. Approximately 0.3 seconds as a result of forced discharge. . Use the standby supply capacitor in the range of 0.22 µF to 0.47 µF. The VN trace for standby OFF changes and speaker turn-ON transient noise is increased significantly when the capacitor is 1 µF or greater. If the standby function is not used, this capacitor must be removed and pin 9 must be pulled up to the power supply. . The output capacitor’s recommended value for C O is 1,000 µF. Smaller capacitance will worsen the roll-off frequency fL and PO in a low range. . The recommended power supply capacitor is approximately 2,200 µF, but other capacitors than 2,200 µF can be used according to the application’s design. Using a capacitor with this value, the load on the supply can be as high as 56 Ω while still providing good supply stability during momentary supply glitches. Note that using a 0.15 µF capacitor can cause oscillations if the supply impedance increases. (Example: Mild oscillation results if the power supply capacitor is open.) . STANDBY pin 9 IC internal circuit . MUTE pin 10 IC internal circuit No.3680-9/20 LA4485 . Input pin 1/2 IC internal circuit . Output pin 11/13 IC internal circuit LS VCC SS VCC Bias Standby line Driver Power transistor Driver Power transistor Upward/Downward PNP Driver Format LS GND . The minimum configuration for dual-mode operation No standby function SVRR 6 40 dB CO = 1000 µF CIN = 2.2 µF (Four-point method) No.3680-10/20 LA4485 . Insert capacitors of 1000 pF between each input and ground to prevent external noise. . When the load (R ) or the supply voltage (V ) is increased, turning the standby switch or the main switch on under strong L CC input conditions will activate the IC’s internal pseudo ASO protection circuit for the upper power transistor (VCE × ICP). This causes output oscillations or intermittent operation (The reference area is shown in Figure 1 below). However, strong input tests after the bias has stabilized have no problems. They also protect the upper power transistors close to the limits of ASO when all signal switches are on. Therefore, when using this IC under these conditions, the circuit design should obey the following condition: Signal generation time > Start-up time of the power amplifier IC or some other method of attaining the zero-volume condition should be adopted. . An undervoltage protection circuit operates when the voltage is 7.5 V or lower. Input voltage, VIN – mV rms This figure shows the pseudo ASO protection area when strong signal is input, and switch is ON: the upper power transistors have an area where VCE × ICP load is caused. PHOTO-2 VCC = 15 V RL = 3 Ω PHOTO-1 VCC = 13.2 V RL = 2 Ω RL = 4 Ω Design center Dual-mode operation f = 1 kHz Dual channel drive Non-inductive load Ta = 25°C Standby switch ON in a typical application Supply voltage, VCC – V Strong signal input after switch-ON is OK. In BTL-mode operation, the load is RL × 2 Figure 1 No.3680-11/20 LA4485 The operating condiations for the PHOTO-1 series in dual mode are VCC = 13.2 V, RL = 2 Ω, f = 1 kHz, VIN = 50 mV and standby switch ON. i) ‘‘X-Y path observed within the normal area’’: checking each channel Stabilization VCE – V Transition icp – A icp – A Output waveforms Current and voltage waveforms Power transistor ↓ CE voltage – V Power transistor CE voltage – V VCE – V * Plot each point on the power transistor ASO curve. Refer to Figure 2. icp – A ICP (Y) VCE (X) Transition Stabilization IE – VCB Emitter current, IE – A ‘‘VCC – VCE’’ added, heavy load Upper power transistor The load line becomes more closely aligned with the vertical axis because of the load. Shifting load line at start-up under large-signal conditions Collector-base voltage, VCB – V Figure 2 No.3680-12/20 LA4485 ii) The operating conditions for the PHOTO-2 in dual mode are VCC = 15 V, RL = 3 Ω, f = 1 kHz, VIN = 100 mV and standby switch ON. ‘‘X-Y path observed within the normal area’’ Output waveforms Stabilization icp – A icp – A Transition Current and voltage waveforms ↓ Power transistor CE voltage – V Power transistor CE voltage – V icp – A VCE – V * Plot each point on the power transistor ASO curve. Refer to Figure 3. Transition Stabilization Emitter current, IE – A IE – VCB Shifting load line at start-up under large-signal conditions Collector-base voltage, VCB – V Figure 3 No.3680-13/20 LA4485 LA4485, BTL Sample Application Circuit Noninverting Inverting THD – PO Output power, PO – W Total harmonic distortion, THD – % PO – VIN Input voltage, VIN – mV Output power, PO – W No.3680-14/20 LA4485 f Response Response – dB Output power, PO – W PO – VCC Frequency, f – Hz ICC – PO Current drain, ICC – A Total harmonic distortion, THD – % Supply voltage, VCC – V THD – f Frequency, f – Hz Pd – PO Power dissipation, Pd – W Power dissipation, Pd – W Allowable power dissipation, Pd max – W Output power, PO – W Pd – PO Output power, PO – W Pd max – VCC Output power, PO – W Supply voltage, VCC – V No.3680-15/20 LA4485 BTL Speaker terminal VCC = 13.2 V, standby +5 V, RL = 4 Ω, Rg = 0 Main switch ON/OFF test BTL Speaker terminal VCC = 13.2 V, standby +5 V, RL = 4 Ω, Rg = 0 Standby switch ON/OFF test Noninverting BTL Inverting VCC = 13.2 V RL = 4 Ω Rg = 0 Mute ON/OFF Measurement Noninverting Inverting BTL → Note: Switching noise decreases as CIN = 0.22 µF (input) is increased. (ex. 2.2 µF) VCC = 13.2 V, RL = 4 Ω, Rg = 600 Ω, THD = 10%, f = 1 kHz Output DC waveform No.3680-16/20 LA4485 BTL-mode Operation Notes In BTL mode, channel 1 should be non-inverted and channel 2 should be inverted. Use the input capacitor CIN in the range 0.22 µF to 2.2 µF. Use the standby supply capacitor in the range 0.22 µF to 1.0 µF. When the capacitor is 2.2 µF or more, the VN trace for standby-off changes, and the switching noise increases significantly. The recommended DC (filter) capacitor is 100 µF or greater. The BTL-mode coupling capacitor should be 2.2 µF. When this capacitor is decreased, the output power is decreased. However, when this capacitor is increased, speaker turn-ON transient noise is increased significantly. In BTL mode, the ripple rejection ratio (SVRR) is approximately 40 dB. This is because the output ripple portion of the noninverted side penetrates the BTL coupling end, so that ripple on the inverted side is large. The following method is described as one external measure: . . . . . LS VCC SS VCC This measure yields an SVRR of approximately 50 dB. Note that the Rx loss voltage is approximately 1 V, and the PO loss is about 1.0 to 1.5 W (to the 15 W level). . Example of minimum parts for BTL operation Noninverting No standby function SVRR 6 40 dB CIN = 2.2 µF CBTL = 2.2 µF (Three point method) Inverting Dual-mode short-circuit test circuit 1 Load short-circuit (to ground) 2 Output-to-supply short-circuit 3Output-to-ground short-ciruit No.3680-17/20 LA4485 . Taking BTL coupling into consideration, the output-to-supply/output-to-ground protector is two-sided in order to protect both the IC and the speaker. Short-circuit to GND protection Self-holding positive feedback circuit Current × voltage detector Reset circuit CH1/CH2 Upper/lower power transistor control When using this method (simultaneously shorting the outputs to supply and to ground) In BTL mode, the IC protection function works even in noninverted output → output-to-supply mode, inverted output → output-to-ground mode. (The reverse is also OK.) Reference Value (a) Short-circuit test for dual-mode operation after the main and standby switches are turned ON. Conditions: 1 VCC = 10 to 16 V, RL = 4 Ω and PO = 1 to 5 W (variable) for load short-circuit 2 VCC = 10 to 16 V, RL = 4 Ω, Rg = 0 (no signal) for output-to-supply short-circuit 3 VCC = 10 to 16 V, RL = 4 Ω, Rg = 0 (no signal) for output-to-ground short-circuit. Z: impedance j: no device breakdown 1 Load short-circuit 2 Output-to-supply short-circuit One-time test 3 Output-to-ground short-circuit Repeated switching test One-time test Repeated switching test Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω j j j j j j j j j (b) Short-circuit test for dual-mode operation (opposite flow of (a)) after the main and standby switches are turned ON. Conditions: same as (a) j: No device breakdown 1 Load short-circuit 2 Output-to-supply short-circuit One-time test j 3 Output-to-ground short-circuit Repeated switching test One-time test Repeated switching test Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω j j j j j j j j (Note) Shorting the outputs to ground when muting is active can result in device breakdown. . BTL-mode short-circuit test circuit Noninverting Inverting 1 Load short-circuit 2 Output-to-supply short-circuit 3 Output-to-ground short-circuit No.3680-18/20 LA4485 Reference Value (a) Short-circuit test for BTL-mode operation after the main and standby switches are turned ON. Conditions: 1 VCC = 10 to 16 V, RL = 4 Ω and PO = 1 to 15 W (variable) for load short-circuit 2 VCC = 10 to 16 V, RL = 4 Ω, Rg = 0 (no signal) for output-to-supply short-circuit 3 VCC = 10 to 16 V, RL = 4 Ω, Rg = 0 (no signal) for output-to-ground short-circuit. Z: impedance j: no device breakdown 1 Load short-circuit 2 Output-to-supply short-circuit One-time test 3 Output-to-ground short-circuit Repeated switching test One-time test Repeated switching test Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω j j j j j j j j j (b) Short-circuit test for BTL-mode operation (opposite flow of (a)) after the main and standby switches are turned ON. Conditions: same as (a) j: No device breakdown 1 Load short-circuit 2 Output-to-supply short-circuit One-time test j 3 Output-to-ground short-circuit Repeated switching test One-time test Repeated switching test Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω Z=0 Z = 0.5 Ω j j j j j j j j (Note) Shorting the outputs to ground when muting is active can result in device breakdown. . Power supply positive surge JASO test The power supply line positive surge breakdown margin has been increased by using the built-in overvoltage protection circuits (VCCX = 28 V) to cut off all bias circuits/change the base-emitter reverse of the output stage. In other words, the breakdown margin is being raised by changing output stage groups that operate as the VCEO (VCER) type to the VCES (VCBO) type. No.3680-19/20 LA4485 . Test of application of +V CC to output pins If the power supply pin is floating under the power supply capacitor insertion conditions, and +VCC comes into contact with output lines (a) and (b) as shown in the diagram above, the IC’s internal upper power transistor will generally be damaged. The LA4485 has a protective bypass circuit on chip. However, it is dangerous if the power supply capacitor is greater than 2200 µF. Floating No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or indirectly cause injury, death or property loss. Anyone purchasing any products described or contained herein for an above-mentioned use shall: 1 Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated with such use: 2 Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. SANYO 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 July, 1996. Specifications and information herein are subject to change without notice. No.3680-20/20