ST TDA7492P User Manual

TDA7492P

25-watt + 25-watt dual BTL class-D audio amplifier

Features

■25 W + 25 W continuous output power at THD = 10% with VCC = 20 V and RL = 8 Ω

■Wide-range single-supply operation (8 - 26 V)

■High efficiency (η = 90%)

■Four selectable, fixed gain settings of nominally 21.6 dB, 27.6 dB, 31.1 dB and 33.6 dB

■Differential inputs minimize common-mode noise

PowerSSO-36

with exposed pad down

■Standby and mute features

■Short-circuit protection

■Thermal overload protection

■Externally synchronizable

■ECOPACK®, environmentally-friendly package

Table 1. Device summary

Description

The TDA7492P is a dual BTL class-D audio amplifier with single power supply, designed for LCD TVs and monitors.

Thanks to the high efficiency and exposed-pad- down (EPD) package no heatsink is required.

Order code	Operating temp. range	Package	Packaging
TDA7492P	-40 to 85 °C	PowerSSO-36 EPD	Tube
TDA7492P13TR	-40 to 85 °C	PowerSSO-36 EPD	Tape and reel

September 2011

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www.st.com

Contents	TDA7492P

Contents

1	Device block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. 5
2	Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		6
	2.1	Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	6
	2.2	Pin list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	7
3	Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		8
	3.1	Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
	3.2	Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
	3.3	Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
4	Characterization curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		10
	4.1	Characterizations for 6 Ω loads with 18 V . . . . . . . . . . . . . . . . . . . . . . . .	10
	4.2	Characterizations for 8 Ω loads with 20 V . . . . . . . . . . . . . . . . . . . . . . . .	13
5	Applications circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		17
6	Applications information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		18
	6.1	Mode selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	18
	6.2	Gain setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	19
	6.3	Input resistance and capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	19
	6.4	Internal and external clocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	20

6.4.1 Master mode (internal clock) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 6.4.2 Slave mode (external clock) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

6.5 Output low-pass filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 6.6 Protection functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.7 Diagnostic output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

7	Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	23
8	Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	25

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TDA7492P	List of tables

List of tables

Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table 2. Pin description list. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Table 3. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 4. Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 5. Electrical specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 6. Mode settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 7. Gain settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 8. How to set up SYNCLK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Table 9. PowerSSO-36 EPD dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Table 10. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

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List of figures	TDA7492P

List of figures

Figure 1.	Internal block diagram (showing one channel only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. 5
Figure 2.	Pin connections (top view, PCB view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. 6
Figure 3.	Output power vs. supply voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	10
Figure 4.	THD at 1 kHz vs. output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	10
Figure 5.	THD at 100 Hz vs. output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	11
Figure 6.	THD at 1 W vs. frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	11
Figure 7.	Frequency response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	11
Figure 8.	Crosstalk vs frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	12
Figure 9.	FFT 0 dB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	12
Figure 10.	FFT -60 dB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	12
Figure 11.	Output power vs supply voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	13
Figure 12.	THD at 1 kHz vs output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	13
Figure 13.	THD at 100 Hz vs output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	14
Figure 14.	THD at 1 W vs frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	14
Figure 15.	Frequency response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	14
Figure 16.	Crosstalk vs frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	15
Figure 17.	FFT 0 dB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	15
Figure 18.	FFT -60 dB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	15
Figure 19.	Test board (SZ-LAB-TDA7492P) layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	16
Figure 20.	Applications circuit for class-D amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	17
Figure 21.	Standby and mute circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	18
Figure 22.	Turn-on/off sequence for minimizing speaker “pop” . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	18
Figure 23.	Device input circuit and frequency response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	19
Figure 24.	Master and slave connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	20
Figure 25. Typical LC filter for a 8-Ω speaker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		21
Figure 26. Typical LC filter for a 4-Ω speaker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		21
Figure 27.	Behavior of pin DIAG for various protection conditions . . . . . . . . . . . . . . . . . . . . . . . . . . .	22
Figure 28.	PowerSSO-36 EPD outline drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	24

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TDA7492P	Device block diagram

1 Device block diagram

Figure 1 shows the block diagram of one of the two identical channels of the TDA7492P.

Figure 1. Internal block diagram (showing one channel only)

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Pin description	TDA7492P

2 Pin description

2.1Pinout

Figure 2. Pin connections (top view, PCB view)

SUB_GND																				VSS
																	36
			1
OUTPB																	35			SVCC
			2
OUTPB			3														34			VREF
PGNDB			4														33			INNB
PGNDB			5														32			INPB
PVCCB			6														31			GAIN1
PVCCB			7														30			GAIN0
OUTNB			8														29			SVR
OUTNB			9														28			DIAG
OUTNA			10														27			SGND
OUTNA			11														26			VDDS
PVCCA			12														25			SYNCLK
PVCCA			13		Exposed pad down												24			ROSC
PGNDA			14														23			INNA
PGNDA			15		(Connect to ground)												22			INPA
OUTPA			16														21			MUTE
OUTPA			17														20			STBY
PGND			18														19			VDDPW

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TDA7492P	Pin description

2.2Pin list

	Table 2.	Pin description list
	Number	Name	Type	Description
	1	SUB_GND	PWR	Connect to the frame
	2,3	OUTPB	O	Positive PWM for right channel
	4,5	PGNDB	PWR	Power stage ground for right channel
	6,7	PVCCB	PWR	Power supply for right channel
	8,9	OUTNB	O	Negative PWM output for right channel
	10,11	OUTNA	O	Negative PWM output for left channel
	12,13	PVCCA	PWR	Power supply for left channel
	14,15	PGNDA	PWR	Power stage ground for left channel
	16,17	OUTPA	O	Positive PWM output for left channel
	18	PGND	PWR	Power stage ground
	19	VDDPW	O	3.3-V (nominal) regulator output referred to ground for power stage
	20	STBY	I	Standby mode control
	21	MUTE	I	Mute mode control
	22	INPA	I	Positive differential input of left channel
	23	INNA	I	Negative differential input of left channel
	24	ROSC	O	Master oscillator frequency-setting pin
	25	SYNCLK	I/O	Clock in/out for external oscillator
	26	VDDS	O	3.3-V (nominal) regulator output referred to ground for signal
				blocks
	27	SGND	PWR	Signal ground
	28	DIAG	O	Open-drain diagnostic output
	29	SVR	O	Supply voltage rejection
	30	GAIN0	I	Gain setting input 1
	31	GAIN1	I	Gain setting input 2
	32	INPB	I	Positive differential input of right channel
	33	INNB	I	Negative differential input of right channel
	34	VREF	O	Half VDDS (nominal) referred to ground
	35	SVCC	PWR	Signal power supply
	36	VSS	O	3.3-V (nominal) regulator output referred to power supply
	-	EP	PWR	Exposed pad for connection to ground plane as heatsink

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Electrical specifications	TDA7492P

3 Electrical specifications

3.1Absolute maximum ratings

	Table 3.	Absolute maximum ratings
	Symbol	Parameter	Value	Unit
	VCCMAX	DC supply voltage for pins PVCCA, PVCCB, SVCC	30	V
	VI	Voltage limits for input pins STANDBY, MUTE, INNA, INPA,	-0.3 to 3.6	V
		INNB, INPB, GAIN0, GAIN1
	Top	Operating temperature	-40 to 85	°C
	Tj	Junction temperature	-40 to 150	°C
	Tstg	Storage temperature	-40 to 150	°C

3.2Thermal data

Table 4.	Thermal data
Symbol	Parameter	Min	Typ	Max	Unit
Rth j-case	Thermal resistance, junction to case	-	2	3	°C/W
R	Thermal resistance, junction to ambient	-	24 (1)	-	°C/W
th j-amb

1. FR4 with vias to copper area of 9 cm2

3.3Electrical specifications

Unless otherwise stated, the results in Table 5 below are given for the conditions:

VCC = 20 V, RL (load) = 8 Ω, ROSC = R3 = 39 kΩ, C8 = 100 nF, f = 1 kHz, GV = 21.6 dB, and Tamb = 25 °C.

	Table 5.	Electrical specifications
	Symbol	Parameter	Condition	Min	Typ	Max	Unit
	VCC	Supply voltage for	-	8	-	26	V
		pins PVCCA, PVCCB, SVCC
	Iq	Total quiescent	-	-	26	35	mA
	IqSTBY	Quiescent current in standby	-	-	2.5	5.0	µA
	VOS	Output offset voltage	Play mode	-	-	±100	mV
			Mute mode	-	-	±60	mV
	IOCP	Overcurrent protection threshold	RL = 0 Ω	3.8	4.2	-	A
	TjSD	Junction temperature at thermal	-	-	150	-	°C
		shutdown
	Ri	Input resistance	Differential input	48	60	-	kΩ

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