MAXIM MAX13325, MAX13326 User Manual

19-5136; Rev 3; 6/10

EVALUATION KIT

AVAILABLE

Dual Automotive, Audio Line Drivers

with I2C Control and Diagnostic

General Description

The MAX13325/MAX13326 dual audio line drivers provide
a reliable differential interface between automotive audio
components. The devices feature differential inputs and
outputs, integrated output diagnostics, and are controlled
using an I2C interface or operate in stand-alone mode.
The outputs can deliver up to 4V

The MAX13325 buffers analog audio signals for trans­mission over long cable distances with a fixed gain of
12dB, whereas the MAX13326 provides a 0dB fixed
gain. The diagnostics on the outputs report conditions
on a per channel basis, including short to GND, short
to battery, overcurrent, overtemperature, and excessive
offset. The output amplifiers can drive capacitive loads
up to 4nF to ground and 3nF differentially.

The outputs are protected according to IEC 61000-4-2
Q8kV Contact Discharge, and Q15kV Air Gap. The

MAX13325/MAX13326 are specified from -40NC to

+105NC and are available in a 28-pin TSSOP package
with an exposed pad.

Applications

Automotive Radio and Rear Seat Entertainment

Professional Remote Audio Amplifiers

into 100I loads.

RMS

Features

S Comprehensive Programmability and Diagnostics

Using I2C Interface

S Autoretry Function in Stand-Alone Mode
S Drive Capacitive Loads ≤ 3nF Differentially, ≤ 4nF

to Ground

S 112dB Signal-to-Noise Ratio
S Low 0.002% THD at 4V
S High PSRR (70dB at 1kHz)
S High CMRR (80dB at 1kHz)
S Low Output Noise (3µV
S Excellent Channel-to-Channel Matching
S Load-Dump Transient Protection
S Protected Output Against Various Short-Circuit

Conditions

S ESD Protection for ±8kV Contact Discharge,

±15kV Air Gap

S Long-Distance Drive Capability Typically Up to

15m or Greater

S Noise-Rejecting Differential Inputs and Outputs
S Low-Power Shutdown Mode < 10µA
S Hardware or Software MUTE Function
S 28-Pin TSSOP Package with Exposed Pad

into 2.7kI Loads

RMS

), MAX13326

RMS

MAX13325/MAX13326

Typical Operating Circuit

V

C6

100nF

MICROPROCESSOR

FROM AUDIO

SOURCE

FROM AUDIO

SOURCE

C1

DIAGNOSTIC

MAX13325
MAX13326

OUTPUT

470nF

CHARGE

PUMP

BIAS

CHOLDCMCP

PROTECTION

+5V

V

L

ADD1

ADD0

SDA

2

C INTERFACE

I

SCL

AND

DIGITAL CONTROL

TO

FLAG

SHDN

MUTE

C7

2.2µF
INLP

INLM

C8

2.2µF

C9

2.2µF
INRP

INRM

C10

2.2µF

*OPTIONAL : NEEDED FOR AUTOMOTIVE LOAD DUMP PROTECTION ONLY
**USE D2 WHEN CHARGE PUMP IS OFF AND EXTERNAL SUPPLY IS PROVIDED TO C HOLD

LEFT

RIGHT

SUP

D2**

V

DD

PGND

BIAS

CSS

GND

OUTLP

OUTLM

OUTRP

OUTRM

* OPTIONAL

C2

µF

1

ESD

+12V

C4
10µF

C5
220nF

Q1

1nF

1nF

R1

1kI

D1

1nF

1nF

1nF

1nF

Ordering Information

PART

MAX13325GUI/V+ 28 TSSOP-EP*

C3
1µF

MAX13326GUI/V+ 28 TSSOP-EP*

/V Denotes an automotive qualified part.
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.

PIN­PACKAGE

TEMP RANGE

-40NC to
+105NC

-40NC to
+105NC

GAIN

(dB)

12

0

_______________________________________________________________ Maxim Integrated Products 1

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.

Dual Automotive, Audio Line Drivers
with I2C Control and Diagnostic

ABSOLUTE MAXIMUM RATINGS

VDD to PGND ........................................................-0.3V to +28V

CHOLD .................................................................-0.3V to +28V

VL to GND ...............................................................-0.3V to +6V

GND, PGND ........................................................-0.3V to +0.3V

OUT_ to PGND ........................................................ -0.3V to 28V

IN_, BIAS to AGND ..................................-0.3V to (VDD + 0.3V)

SCL, SDA, ADD0, ADD1, MUTE, SHDN,

FLAG to GND ..........................................................-0.3V to +6V

OUT_ Short Circuit to PGND or VDD .........................Continuous

Short Circuits Between Any OUT_ ............................ Continuous

Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-

layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

MAX13325/MAX13326

(VDD = 14.4V, VL = 5V, RL = J, load impedance from OUT_+ to OUT_-, TA = TJ = -40NC to +105NC, typical values are TA = +25NC,
unless otherwise noted.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

AMPLIFIER DC CHARACTERISTICS

Transient Supply Voltage
(Load Dump)

Operating Supply Voltage Range

VDD OVLO Threshold V
VDD UVLO Threshold V
VL UVLO Threshold V

Supply Current I

Logic Supply Current I

Shutdown Supply Current I

Turn-On Time (from Shutdown)
Turn-On Time (from Mute)
Differential Input Resistance R

Single-Ended Input Impedance R

Signal-Path Gain (Note 3) A

Channel-to-Channel Gain
Tracking

V

DDMAX

V

DDOV

DDUV

SHDN

DD

V

LUV

DD

INDIF

Using external nMOS-RTR020N05, 300ms
duration

L

Rising edge 18.5 19.2 V
Falling edge 3.3 3.5 V
Falling edge 2.2 2.4 V
TA = +25NC, no load
TA = -40NC to +105NC, no load
VL = 5V 1.7 mA

L

I

DD

I

L

MUTE = VL
SHDN = VL, C

Measure across input 18 24 30

Each input to ground (MAX13325) 15 20 25

IN

Each input to ground (MAX13326) 12 16 20

MAX13325 11.8 12 12.2

V

MAX13326 -0.2 0 +0.2

Continuous Power Dissipation (TA = +70NC) (multilayer board)

28-Pin TSSOP (derate 27mW/NC above +70NC) ..... 2162.2mW

Junction-to-Ambient Thermal Resistance (BJA)

(Note 1) ........................................................................ 37NC/W

Operating Temperature Range ........................ -40NC to +105NC

Storage Temperature Range ............................ -65NC to +150NC

Junction Temperature .....................................................+150NC

Lead Temperature (soldering, 10s) ................................+300NC

Soldering Temperature (reflow) ......................................+260NC

50 V

4.5 18

2.7 5.5

39 mA

50 mA

TA = +25NC
TA = -40NC to +105NC

= 220nF

CSS

0.5 10

0.5

< 0.1 2

220 ms

6 ms

Q0.4

V

FA

FA

kI

kI

dB

dB

2 ______________________________________________________________________________________

Dual Automotive, Audio Line Drivers

with I2C Control and Diagnostic

ELECTRICAL CHARACTERISTICS (continued)

(VDD = 14.4V, VL = 5V, RL = J, load impedance from OUT_+ to OUT_-, TA = TJ = -40NC to +105NC, typical values are TA = +25NC,
unless otherwise noted.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Differential Mode Output Balance
OUT_+ to OUT_- (Note 4)

Output Offset Voltage
(OUT_+ to OUT_-)

BIAS Voltage V
BIAS Impedance Z

Output-Voltage Swing Differential

Power-Supply Rejection Ratio PSRR

Common-Mode Rejection Ratio CMRR VIN = 1V

AMPLIFIER AC CHARACTERISTICS

Total Harmonic Distortion Plus
Noise (Note 5)

Total Harmonic Distortion Plus
Noise at VDD = 5V (Note 5)

Capacitive-Load Stability 3 nF

Capacitive-Load Drive Capability

Signal-to-Noise Ratio (Note 5) SNR

Unity-Gain Bandwidth 3 MHz
Output Slew Rate 2.5

Output-Voltage Noise

Crosstalk VIN = 1V
Mute Time To achieve soft mute, C
Mute Attenuation VIN = 1V
Click-and-Pop Level (Note 6) K
Click-and-Pop Level (Note 6) K

V

OOS

BIAS

BIAS

THD+N

THD+N

CP

CP

MUTE = GND, TA = +25NC
MUTE = VL, TA = +25NC

Relative to V
I

BIAS

VDD = 14.4V, VIN = Q14.4V, RL = 1kI Q12.5
VDD = 5.0V, VIN = Q5V, RL = 1kI Q4.2
VDD = 4.5V to 18V -80 -96

VDD = 14.5V, +500mV

V

OUT

V

OUT

V

OUT

V

OUT

V

OUT

V

OUT

V

OUT

No sustained
oscillation

MAX13325, gain = 12dB, V
A-weighted

MAX13326, gain = 0dB, V
A-weighted

A-weighted, MAX13325 10

A-weighted, MAX13326 3

Into and out of mute -70 dBV
Into and out of shutdown, 1kI

= Q10FA

RMS

= 4V

RMS

= 4V

RMS

= 4V

RMS

= 7V

RMS

= 1V

RMS

= 1V

RMS

= 2V

RMS

RMS

RMS

DD

69 92 115

ripple at 1kHz -95

P-P

ripple at 10kHz -80

P-P

, 100Hz to 10kHz -48 -80 dB

, RL = 2.7kI
, RL = 1kI
, RL = 100I, VDD = 8V
, RL = 1kI
, RL = 2.7kI
, RL = 1kI
, RL = 1kI

C

to GND 4

LOAD

C

differential 3

LOAD

= 4V

OUT

= 4V

OUT

, 1kHz -110 dB

= 220nF 4 ms

CSS

, 1kHz -75 dB

RMS

RMS

,

,

-40 dB

Q0.5 Q10
Q0.2 Q3

50 52.5 %

0.002

0.004

0.03

0.2

0.01

0.02

0.8

112

122

-45 dBV

mV

kI

V

dBVDD = 14.5V, +500mV

%

%

nF

dB

V/Fs

FV

MAX13325/MAX13326

_______________________________________________________________________________________ 3

Dual Automotive, Audio Line Drivers
with I2C Control and Diagnostic

ELECTRICAL CHARACTERISTICS (continued)

(VDD = 14.4V, VL = 5V, RL = J, load impedance from OUT_+ to OUT_-, TA = TJ = -40NC to +105NC, typical values are TA = +25NC,
unless otherwise noted.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

CHARGE PUMP

Charge-Pump Overdrive Voltage,
V

V

Charge-Pump Frequency f

DIAGNOSTICS

Output Current Limit Short to GND or battery 580 mA
Current-Limit Warning Threshold 230 mA

MAX13325/MAX13326

Open-Load Detection 10
Output Offset Detection Valid when muted
Thermal Warning Threshold 135
Thermal Shutdown Threshold 165
Thermal Shutdown Hysteresis 15

ESD PROTECTION

Air Gap IEC 61000-4-2 OUT_ pins
Contact Discharge IEC 61000-4-2 OUT_ pins
HBM All pins

CHOLD

CHOLD

– V

(Hard Mode)

DD

- V

(Soft Mode) V

DD

V

CPH

CPS

CP

VDD = 4.5V, I
VDD = 18V, I

VDD unconnected, I
VL = 3.3V

VL = 5V 3.9

CPOFF = 0

SOURCE

SOURCE

= 6.6mA 3.2 4.0

= 6.6mA 4.5 5.5

SOURCE

= 40FA,

CPF[1:0] = 00 333
CPF[1:0] = 01 190
CPF[1:0] = 10 426
CPF[1:0] = 11 260

2.1

Q250

Q15

Q8
Q2

V

V

kHz

kI

mV

NC
NC
NC

kV
kV
kV

4 ______________________________________________________________________________________

Dual Automotive, Audio Line Drivers

_

−

 

_

OUT_ OUT_

OUT_ OUT

( | V ) ( V )

20 log .

( V ) ( V ) 2

−

+ −

+

 

−

 

×

 

+ ×

 
 

with I2C Control and Diagnostic

DIGITAL CHARACTERISTICS

(VDD = 14.4V, VL = 3.3V, TA = TJ = -40NC to +105NC, typical values are TA = +25NC, unless otherwise noted.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

DIGITAL INTERFACE

Input-Voltage High V

INH

Input-Voltage Low V
Input-Voltage Hysteresis 50 mV
Input Leakage Current Q100 FA
Output Low Voltage FLAG, SDA, I
Output Leakage Current FLAG, SDA = 5.5V 2 FA
Stand-Alone FLAG Pulse Width ADD0, ADD1 = GND 100 ms
Stand-Alone Fault Retry Time ADD0, ADD1 = GND 500 ms

I2C TIMING

Serial-Clock Frequency f
Bus Free Time t
Hold Time t
SCL Low Time t
SCL High Time t
Data Hold Time t
Data Setup Time t

SCL

BUF

HD:STA

LOW

HIGH

HD:DAT

SU:DAT

Bus Capacitance C
Receiving Rise Time t
Receiving Fall Time t
Transmitting Fall Time t
STOP Condition Setup Time t

SU:STO

Pulse Width of Suppressed Spike t

Note 2: All devices are 100% tested at TA = +25NC. Limits over temperature are guaranteed by design.

VL = 2.7V to 5.5V 0.75 x V
VL = 2.7V to 5.5V 0.25 x V

INL

= 3mA 0.4 V

SINK

L

0 400 kHz
Between START and STOP conditions 1.3 Fs
Repeated START condition 0.6 Fs

1.3 Fs

0.6 Fs
0 900 ns

100 ns

Per bus line 400 pF

B

SCL, SDA 20 + 0.1C

R

SCL, SDA 20 + 0.1C

F

SDA, VL = 3.6V 20 + 0.05C

F

B

B

B

0.6 Fs

SP

0 50 ns

L

300 ns
300 ns
250 ns

MAX13325/MAX13326

V
V

Note 3: Signal path gain is defined as:

Note 3: Signal Path Gain is defined as

Note 4: Measured in differential output mode, differential input voltage 4V

Common-mode output balance is defined as:

Common-Mode Output Balance is defined as

Note 5: 22Hz to 22kHz measurement bandwidth.
Note 6: KCP level is calculated as 20log[(peak voltage during mode transition, no input signal)/1V

dBV.

20 log .

 
 

(V ) (V )

 

×

−

OUT_ OUT_

+ −

−

(V ) (V )

IN_ IN

+

(for 0dB gain), 1V

P-P

(for 12dB gain) 1kHz.

P-P

]. Units are expressed in

RMS

_______________________________________________________________________________________ 5

Dual Automotive, Audio Line Drivers
with I2C Control and Diagnostic

Typical Operating Characteristics

(V

= 14.4V, VL = 5V, RL = 1kI, gain = 12dB, TA = +25NC, unless otherwise noted.)

DD

SHUTDOWN CURRENT

COMMON-MODE REJECTION RATIO

vs. TEMPERATURE

0.40

0.35

0.30

0.25

0.20

0.15

SHUTDOWN CURRENT (µA)

0.10

0.05

0

-40

MAX13325/MAX13326

TEMPERATURE (°C)

NO LOAD
INPUTS SHORTED
V

= 0V

SHDN

9580-25 -10 5 35 5020 65

TOTAL HARMONIC DISTORTION PLUS

MAX13325 toc01

0

-10

-20

-30

-40

-50

CMRR (dB)

-60

-70

-80

-90

-100
10 100k

POWER-SUPPLY REJECTION RATIO

NOISE vs. OUTPUT VOLTAGE

MAX13325 toc04

PSRR (dB)

0

500mV

-10

-20

-30

-40

-50

-60

-70

-80

-90

-100

-110

-120
10 100k

0.020

0.018

0.016

0.014

0.012

0.010

THD+N (%)

0.008

0.006

0.004

0.002

0

0 10

OUTPUT VOLTAGE (V

RMS

fIN = 1kHz

986 72 3 4 51

)

vs. FREQUENCY

FREQUENCY (Hz)

vs. FREQUENCY

RIPPLE

P-P

FREQUENCY (Hz)

1V

INPUT

RMS

20kHz AES17 FILTER

10k1k100

10k1k100

MAX13325 toc02

MAX13325 toc05

TOTAL HARMONIC DISTORTION

PLUS NOISE vs. FREQUENCY

0.010

0.009

0.008

0.007

0.006

0.005

THDN (%)

0.004

0.003

0.002

0.001

0

LEFT CHANNEL

RIGHT CHANNEL

10 100k

FREQUENCY (Hz)

CROSSTALK vs. FREQUENCY

0

-10

1V

INPUT

RMS

20kHz AES17 FILTER

-20

-30

-40

-50

-60

-70

-80

CROSSTALK (dB)

-90

-100

-110

-120

-130

-140
10 100k

RIGHT TO LEFT

LEFT TO RIGHT

FREQUENCY (Hz)

1V

OUTPUT

RMS

MAX13325 toc03

10k1k100

MAX13325 toc06

10k1k100

MUTE ATTENUATION vs. FREQUENCY

-60
2V

INPUT

RMS

A-WEIGHTED

-64

-68

-72

MUTE ATTENUATION (dB)

-76

-80

10 100k

LEFT CHANNEL

RIGHT CHANNEL

FREQUENCY (Hz)

OUTPUT-NOISE VOLTAGE vs. FREQUENCY

0

-10

-20

MAX13325 toc07

-30

-40

-50

-60

-70

-80
90

-100

-110

OUTPUT-NOISE VOLTAGE (dBV)

-120

-130

-140

10k1k100

-150
0 20

FREQUENCY (kHz)

MAX13325 toc08

181612 144 6 8 102

0

-15

-30

-45

-60

-75

FFT (dBV)

-90

-105

-120

-135

-150
10 100k

FFT vs. FREQUENCY

V

= 1V

OUT

RMS

1kHz

FREQUENCY (Hz)

6 ______________________________________________________________________________________

MAX13325 toc09

10k1k100

Dual Automotive, Audio Line Drivers

GAIN ERROR (dB)

with I2C Control and Diagnostic

Typical Operating Characteristics (continued)

(V

= 14.4V, VL = 5V, RL = 1kI, gain = 12dB, TA = +25NC, unless otherwise noted.)

DD

MAX13325/MAX13326

0.020

0.015

0.010

0.005

LEFT CHANNEL

0

-0.005

-0.010

-0.015
RIGHT CHANNEL

-0.020

-40
TEMPERATURE (°C)

OUTPUT-NOISE VOLTAGE vs. FREQUENCY

0

MAX13326 (0dB)

-10

-20

-30

-40

-50

-60

-70

-80

-90

-100

-110

OUTPUT NOISE VOLTAGE (dBV)

-120

-130

-140

-150
0 20

FREQUENCY (kHz)

GAIN ERROR vs. TEMPERATURE

OUTPUT VOLTAGE vs. CHARGE-PUMP

OVERDRIVE VOLTAGE

MAX13325 toc12

GAIN ERROR (dB)

0.050

0.045

0.040

0.035

0.030

0.025

0.020

0.015

0.010

0.005

-0.005

-0.010

-0.015

-0.020

-0.025

-0.030

-0.035

-0.040

-0.045

-0.050

10.5

10.0

MAX13325 toc10

9.5

9.0

8.5

- VDD) (V)

THDN = 1%

= 1kHz

f

IN

V

= 14.4

DD

= 1kI

R

L

CPOFF = 1

4.0 4.53.52.5 3.00.5 1.0 1.5 2.0

OUTPUT VOLTAGE (V)

8.0

7.5

9580-25 -10 5 35 5020 65

7.0
0 5.0

(V

CHOLD

GAIN vs. TEMPERATURE

0.20
MAX13326 (0dB)

0.15

VOUT = 1V

MAX13325 toc13

0.10

0.05

0

GAIN (dB)

-0.05

-0.10

-0.15

-0.20

181612 144 6 8 102

-40

RMS

TEMPERATURE (°C)

LEFT CHANNEL

RIGHT CHANNEL

9580-25 -10 5 35 5020 65

MAX13325 toc14

-0.005

-0.010

GAIN ERROR (dB)

-0.015

-0.020

-0.025

-0.030

-0.035

-0.040

-0.045

-0.050

0.050

0.045

0.040

0.035

0.030

0.025

0.020

0.015

0.010

0.005

GAIN ERROR vs. FREQUENCY

1V

OUTPUT

RMS

0

10 100k

FREQUENCY (Hz)

10k1k100

GAIN ERROR vs. FREQUENCY

MAX13326 (0dB)

OUTPUT

1V

RMS

0

10 100k

FREQUENCY (Hz)

10k1k100

MAX13325 toc12

MAX13325 toc15

_______________________________________________________________________________________ 7