ST TDA7718N User Manual

TDA7718N

3 band car audio processor

Features

■Input multiplexer

–QD1: quasi-differential stereo inputs

–SE1: stereo single-ended input

–SE2: stereo single-ended input

–SE3: stereo single-ended input

–FD1 / SE4+SE5: 1 full-differential input or 2 stereo single-ended inputs

■Loudness

–2nd order frequency response

–Programmable center frequency (400 Hz / 800 Hz / 2400 Hz)

–15 dB with 1 dB steps

–Selectable high frequency boost

–Selectable flat-mode (constant attenuation)

■Volume

–+23 dB to -31 dB with 1 dB step resolution

–Soft-step control with programmable blend times

■Bass

–2nd order frequency response

–Center frequency programmable in 4 steps (60 Hz / 80 Hz / 100 Hz / 200 Hz)

–Q programmable 1.0/1.25/1.5/2.0

–DC gain programmable

–-15 dB to 15 dB range with 1 dB resolution

■Middle

–2nd order frequency response

–Center frequency programmable in 4 steps (500 Hz / 1 kHz / 1.5 kHz / 2.5 kHz)

–Q programmable 0.75/1.0/1.25

–-15 dB to 15 dB range with 1 dB resolution

■Treble

–2nd order frequency response

(10 kHz / 12.5 kHz / 15 kHz / 17.5 kHz)

–Center frequency programmable in 4 steps (10 kHz / 12.5 kHz / 15 kHz / 17.5 kHz)

–-15 dB to 15 dB with 1 dB resolution

TSSOP28

■Speaker

–4 independent soft step speaker controls

–+15 dB to -79 dB with 1 dB steps

–Direct mute

■Subwoofer

–2nd order low pass filter with programmable cut off frequency

(55 Hz / 85 Hz / 120 Hz / 160 Hz)

–2 independent soft step level control,

+15 dB to –79 dB with 1 dB steps

■Mute functions

–Direct mute

–Digitally controlled SoftMute with 4 programmable mute-times

(0.48 ms/0.96 ms/8 ms/16 ms)

■Offset detection

–Offset voltage detection circuit for on-board power amplifier failure diagnosis

Description

The TDA7718N is a high performance signal processor specifically designed for car radio applications. The device includes a high performance audioprocessor with fully integrated audio filters and new Soft Step architecture. The digital control allows programming in a wide range of filter characteristics.

Table 1.	Device summary
Order code		Package	Packing
TDA7718N		TSSOP28	Tube
TDA7718NTR		TSSOP28	Tape and reel

October 2009

Doc ID 16502 Rev 1

1/40

www.st.com

Contents	TDA7718N

Contents

1	Block circuit diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		6
2	Pin connection and pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . .		7
	2.1	Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	7
	2.2	Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	7
3	Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		9

3.1 Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.2 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4	Description of the audioprocessor . . . . . . . . . . . . . . . . . . . . . . . . . . . .		13
	4.1	Input stages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	13

4.1.1 Quasi-differential stereo input (QD1) . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.1.2 Single-ended stereo input (SE1, SE2, SE3) . . . . . . . . . . . . . . . . . . . . . 13

4.1.3Full-differential stereo input or single-ended input (FD1/QD2/SE4+SE5) 13

4.2	Loudness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		15
	4.2.1	Loudness attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	15
	4.2.2	Peak frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	15
	4.2.3	High frequency boost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	16
	4.2.4	Flat mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	16

4.3 SoftMute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.4 SoftStep volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.5 Bass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

4.5.1 Bass attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.5.2 Bass center frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.5.3 Quality factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.5.4 DC mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

4.6 Middle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

	4.6.1	Middle attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	20
	4.6.2	Middle center frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	20
	4.6.3	Quality factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	21
4.7	Treble .	. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	21

2/40	Doc ID 16502 Rev 1

TDA7718N				Contents
		4.7.1	Treble attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . 21
		4.7.2	Center frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . 22
	4.8	Subwoofer filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . . 22
	4.9	Softstep control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . . 23
	4.10	DC offset detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . . 23
	4.11	Audioprocessor testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . . 25
5	I2C bus specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .			. . . . 26

5.1 Interface protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.2 I2C bus electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

5.2.1 Receive mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 5.2.2 Transmission mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 5.2.3 Reset condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

5.3 Data byte specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6	Package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	38
7	Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	39

Doc ID 16502 Rev 1

3/40

List of tables	TDA7718N

List of tables

Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table 2. Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Table 3. Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 4. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Table 5. Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 6. I2C bus electrical characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Table 7. Subaddress (receive mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 8. Main selector (0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 9. Soft mute / others (4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 10. SoftStep I (5). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 11. SoftStep II / DC detector (6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Table 12. Loudness (7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 13. Volume / output gain (8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 14. Treble filter (9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 15. Middle filter (10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 16. Bass filter (11). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Table 17. Subwoofer / middle / bass (12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Table 18. Speaker attenuation (FL/FR/RL/RR/SWL/SWR) (13-18) . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 19. Testing audio processor 1 (19) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 20. Testing audio processor 2 (20) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Table 21. Testing audio processor 3 (21) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Table 22. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

4/40	Doc ID 16502 Rev 1

TDA7718N	List of figures

List of figures

Figure 1. Block circuit diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Figure 2. Pin connection (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 3. FD / QD / SE block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 4. Loudness attenuation @ fP = 400 Hz. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Figure 5. Loudness center frequencies @ attn. = 15 dB.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 6. Loudness attenuation, fc = 2.4 kHz. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 7. SoftMute timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 8. Bass control @ fC = 80 Hz, Q = 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 9. Bass center frequencies @ gain = 14 dB, Q = 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Figure 10. Bass quality factors @ gain = 14 dB, fC = 80 Hz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 11. Bass normal and DC mode @ gain = 14 dB, fC = 80 Hz . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 12. Middle control @ fC = 1 kHz, Q = 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 13. Middle center frequencies @ gain = 14 dB, Q = 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 14. Middle quality factors @ gain = 14 dB, fC = 1 kHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 15. Treble control @ fC = 17.5 kHz. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Figure 16. Treble center frequencies @ gain = 14 dB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 17. Subwoofer cut frequencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 18. DC offset detection circuit (simplified) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 19. Test circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Figure 20. I2C bus interface protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Figure 21. I2C bus data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 22. TSSOP28 mechanical data and package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Doc ID 16502 Rev 1

5/40

6/40

1

Block

1Rev16502IDDoc

MULTIPLEXERINPUT

.1 Figure

Block

diagram circuit

MUTE

diagramcircuitBlock

diagramcircuit

SOFT

MONO FADER

OUTLF

LOUDNESS

VOLUME

TREBLE

MIDDLE

BASS

MUTE

MONO FADER

OUTRF

SE1L

SE1R

MONO FADER

OUTLR

SE2L

SE2R

MONO FADER

OUTRR

SE3L

SE3R

MONO FADER

OUTSWL

QD1L

QD1G

SUBWOOFER

MONO FADER

OUTSWR

QD1R

MAIN

FD1L+/QD2L/SE4L

FD1L-/QD2G/SE4R

FD1R-/QD2G/SE5L

FD1R+/QD2R/SE5R

DIGITAL

DC-Offset

SUPPLY

I2C BUS

Detector

CONTROL

VCC

GND

CREF

SCL SDA

WIN_IN

WIN_TC

DC_ERR

TDA7718N

TDA7718N	Pin connection and pin description

2 Pin connection and pin description

2.1Pin connection

Figure 2. Pin connection (top view)

SE1L	1	28	Winin
SE1R	2	27	DCErr
SE2L	3	26	SDA
SE2R	4	25	SCL
SE3L	5	24	VCC
SE3R	6	23	MUTE
QD1L	7	22	WINTC
QD1G	8	21	OUTLF
QD1R	9	20	OUTLR
FD1L+/QD2L/SE4L	10	19	OUTRR
FD1L-/QD2G/SE4R	11	18	OUTRF
FD1R-/QD2G/SE5L	12	17	OUTSWL
FD1R+/QD2R/SE5R	13	16	OUTSWR
CREF	14	15	GND

2.2Pin description

Table 2.		Pin description
No.		Pin name	Description	I/O
1		SE1L	Single-end input left	I
2		SE1R	Single-end input right	I
3		SE2L	Single-end input left	I
4		SE2R	Single-end input right	I
5		SE3L	Single-end input left	I
6		SE3R	Single-end input right	I
7		QD1L	quasi-differential stereo inputs left	I
8		QD1G	quasi-differential stereo inputs common	I
9		QD1R	quasi-differential stereo inputs right	I
10	FD1L+/QD2L/SE4L		Full differential + input left or quasi-differential left or single-end input left	I

Doc ID 16502 Rev 1

7/40

Pin connection and pin description				TDA7718N
Table 2.		Pin description (continued)
No.		Pin name		Description	I/O
11	FD1L-/QD2G/SE4R		Full differential - input left or quasi-differential ground or single-end input right		I
12	FD1R-/QD2G/SE5L		Full differential - input right or quasi-differential ground or single-end input left		I
13	FD1R+/QD2R/SE5R		Full differential + input right or quasi-differential right or single-end input right		I
14		CREF	Reference capacitor		O
15		GND	Ground		S
16		OUTSWR	Subwoofer right output		O
17		OUTSWL	Subwoofer left output		O
18		OUTRF	Front right output		O
19		OUTRR	Rear right output		O
20		OUTLR	Rear left output		O
21		OUTLF	Front left output		O
22		WinTC	DC offset detector filter output		O
23		MUTE	External mute pin		I
24		VCC	Supply		S
25		SCL	I2C bus clock		I
26		SDA	I2C bus data		I/O
27		DC_ERR	DC offset detector output		O
28		WIN_IN	DC offset detector input		I

8/40	Doc ID 16502 Rev 1

TDA7718N	Electrical specifications

3 Electrical specifications

3.1Thermal data

Table 3.	Thermal data
Symbol		Description	Value	Unit
Rth-j amb		Thermal resistance junction-to-ambient	114	°C/W

3.2Absolute maximum ratings

Table 4.	Absolute maximum ratings
Symbol		Parameter	Value	Unit
VS		Operating supply voltage	10.5	V
Vin_max		Maximum voltage for signal input pins	7	V
Tamb		Operating ambient temperature	-40 to 85	°C
Tstg		Storage temperature range	-55 to 150	°C

3.3Electrical characteristics

VS = 8.5 V; Tamb= 25 °C; RL= 10 kΩ; all gains = 0 dB; f = 1 kHz; unless otherwise specified

	Table 5.	Electrical characteristics
	Symbol	Parameter	Test condition	Min.	Typ.	Max.	Unit
	Supply
	Vs	Supply voltage	-	7.5	8.5	10	V
	Is	Supply current	-	23	29	35	mA
	Input selector
	Rin	Input resistance	All single ended inputs	70	100	130	kΩ
	VCL	Clipping level	Input gain = 0 dB	2	-	-	VRMS
	SIN	Input separation	-	-	95	-	dB
	Differential stereo inputs
	Rin	Input resistance	Differential	70	100	-	kΩ
	CMRR	Common mode rejection ratio for	VCM = 1 VRMS @ 1 kHz	44	60	-	dB
		main source	VCM = 1 VRMS @ 10 kHz	44	60	-	dB
	eNo	Output noise @ speaker outputs	20 Hz - 20 kHz, A-weighted;	-	12	22	µV
			all stages 0 dB

Doc ID 16502 Rev 1

9/40

Electrical specifications						TDA7718N
Table 5.		Electrical characteristics (continued)
Symbol		Parameter	Test condition	Min.	Typ.	Max.	Unit
Loudness control
AMAX		Max attenuation	-	14	15	16	dB
ASTEP		Step resolution	-	0.5	1	1.5	dB
			fP1	-	400	-	Hz
fPeak		Peak frequency	fP2	-	800	-	Hz
			fP3	-	2400	-	Hz
Volume control
GMAX		Max gain	-	22	23	24	dB
AMAX		Max attenuation	-	-	-31	-30	dB
ASTEP		Step resolution	-	0.5	1	1.5	dB
EA		Attenuation set error	-	-0.75	0	+0.75	dB
ET		Tracking error	-	-	-	2	dB
VDC		DC steps	Adjacent attenuation steps	-3	0.1	3	mV
			From 0 dB to GMIN	-5	0.5	5	mV
Soft mute
AMUTE		Mute attenuation	-	80	100	-	dB
			T1	0.35	0.48	0.65	ms
TD		Delay time	T2	0.7	0.96	1.3	ms
			T3	5.6	7.6	9.6	ms
			T4	12.3	15.3	18.3	ms
VTH Low		Low threshold for SM pin	-	-	-	1	V
VTH High		High threshold for SM pin	-	2.5	-	-	V
RPU		Internal pull-up resistor	-	32	45	58	kΩ
VPU		Internal pull-up voltage	-	3	3.3	3.6	V
Bass control
			fC1	-	60	-	Hz
Fc		Center frequency	fC2	-	80	-	Hz
			fC3	-	100	-	Hz
			fC4	-	200	-	Hz
			Q1	-	1	-	-
QBASS		Quality factor	Q2	-	1.25	-	-
			Q3	-	1.5	-	-
			Q4	-	2	-	-
CRANGE		Control range	-	±14	±15	±16	dB
ASTEP		Step resolution	-	0.5	1	1.5	dB
DCGAIN		Bass-DC-gain	DC = off	-1	0	+1	dB
			DC = on, gain = ±15 dB	±4.3	±4.7	±5.1	dB

10/40

Doc ID 16502 Rev 1

	TDA7718N			Electrical specifications
	Table 5.	Electrical characteristics (continued)
	Symbol	Parameter	Test condition	Min.	Typ.	Max.	Unit
	Middle control
	CRANGE	Control range	-	±14	±15	±16	dB
	ASTEP	Step resolution	-	0.5	1	1.5	dB
			fC1	-	500	-	Hz
	fc	Center frequency	fC2	-	1	-	kHz
			fC3	-	1.5	-	kHz
			fC4	-	2.5	-	kHz
			Q1	-	0.75	-	-
	QMIDDLE	Quality factor	Q2	-	1	-	-
			Q3	-	1.25	-	-
	Treble control
	CRANGE	Clipping level	-	±14	±15	±16	dB
	ASTEP	Step resolution	-	0.5	1	1.5	dB
			fC1	-	10	-	kHz
	fc	Center frequency	fC2	-	12.5	-	kHz
			fC3	-	15	-	kHz
			fC4	-	17.5	-	kHz
	Speaker attenuators
	GMAX	Max gain	-	14	15	16	dB
	AMAX	Max attenuation	-	-	-79	-74	dB
	ASTEP	Step resolution	-	0.5	1	1.5	dB
	AMUTE	Mute attenuation	-	80	90	-	dB
	EE	Attenuation set error	-	-	-	2	dB
	VDC	DC steps	Adjacent attenuation steps	-	0.1	5	mV
	Audio outputs
	VCL	Clipping level	d = 0.3 %; byte8_D6=1	2	-	-	VRMS
			d = 1 %; byte8_D6=0	2.2	-	-	VRMS
	ROUT	Output impedance	-	-	30	100	Ω
	RL	Output load resistance	-	2	-	-	kΩ
	CL	Output load capacitor	-	-	-	10	nF
	VDC	DC voltage level	-	3.8	4.0	4.2	V
	Subwoofer lowpass
			fLP1	-	55	-	Hz
	fLP	Lowpass corner frequency	fLP2	-	85	-	Hz
			fLP3	-	120	-	Hz
			fLP4	-	160	-	Hz

Doc ID 16502 Rev 1

11/40

	Electrical specifications					TDA7718N
	Table 5.	Electrical characteristics (continued)
	Symbol	Parameter	Test condition	Min.	Typ.	Max.	Unit
	DC offset detection circuit
			V1	±10	±25	±40	mV
	Vth	Zero comp. window size	V2	±30	±50	±70	mV
			V3	±50	±75	±100	mV
			V4	±70	±100	±130	mV
			-	2	11	30	µs
	tsp	Max rejected spike length	-	5	22	50	µs
			-	10	33	70	µs
			-	15	44	90	µs
	ICHDCErr	DCErr charge current	-	2	5	8	µA
	IDISDCErr	DCErr discharge current	-	4	5	9	mA
	VOutH	DCErr high voltage	-	3	3.3	3.6	V
	VOutH	DCErr low voltage	-	-	100	300	mV
	General
			BW=20 Hz to 20 kHz A-	-	12	22	µV
			Weighted, all gain = 0 dB
	eNO	Output noise
			BW=20 Hz - 20 kHz A-	-	7	12	µV
			Weighted, Output muted
	S/N	Signal to noise ratio	all gain = 0 dB, A-weighted;	98	104	-	dB
			Vo = 2 VRMS
	D	Distortion	VIN =1 VRMS; all stages 0 dB	-	0.01	0.1	%
	SC	Channel separation left/right	-	-	90	-	dB

12/40

Doc ID 16502 Rev 1