19-1461; Rev 0; 4/99
Serially Controlled, Clickless
Audio/Video Switches
The MAX4562/MAX4563 serial-interface controlled
switches are ideal for multimedia applications. Each
device features 30Ω max on-resistance (RON), 5Ω RON
match, and 5Ω RON flatness. Audio off-isolation and
crosstalk at 20kHz is -85dB, and video off-isolation and
crosstalk at 10MHz is -55dB. Both devices feature
“clickless” mode operation for audio applications.
The MAX4562/MAX4563 contain two normally open single-pole/double-throw (SPDT) switches and two normally open single-pole/single-throw (SPST) switches. The
MAX4562 features a 2-wire I 2 C™-compatible serial
interface. The MAX4563 features a 3-wire SPI™/QSPI™/
MICROWIRE™-compatible serial interface. Both parts
are available in 16-pin QSOP packages and operate
over the commercial and extended temperature
ranges.
Applications
Features
♦ Selectable Soft-Switching Mode for “Clickless”
Audio Operation
♦ 30Ω max On-Resistance
♦ Audio Performance
-85dB Off-Isolation at 20kHz
-85dB Crosstalk at 20kHz
-0.007% THD
♦ Video Performance
-55dB Off-Isolation at 10MHz
-55dB Crosstalk at 10MHz
♦ T-Switch Configurable for Improved Off-Isolation
♦ Serial Interface
2-Wire I2C-Compatible (MAX4562)
3-Wire SPI/QSPI/MICROWIRE-Compatible
(MAX4563)
♦ Single-Supply Operation from +2.7V to +5.5V
Set-Top Boxes
PC Multimedia Boards
Audio Systems
Ordering Information
Video Conferencing Systems
PART
Pin Configuration
TEMP. RANGE
PIN-PACKAGE
MAX4562CEE
0°C to +70°C
16 QSOP
MAX4562EEE
MAX4563CEE
MAX4563EEE
-40°C to +85°C
0°C to +70°C
-40°C to +85°C
16 QSOP
16 QSOP
16 QSOP
TOP VIEW
V+ 1
NO1A 2
16 SCL (SCLK)
Typical Operating Circuit
MAX4562 15 SDA (DIN)
MAX4563
COM1 3
14 A0 (CS)
NO1B 4
13 A1 (DOUT)
12 NO4
GND 5
SIGNAL IN
NO2A 6
11 COM4
COM2 7
10 NO3
NO2B 8
9
NO2A
COM2
NO2B
SIGNAL OUT
COM3
COM3
QSOP
NO3
( ) ARE FOR MAX4563
I2C is a trademark of Philips Corp.
SPI/QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
MAX4562/MAX4563
General Description
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
ABSOLUTE MAXIMUM RATINGS
V+ to GND ................................................................-0.3V to +6V
NO_ _, COM_, DOUT to GND (Note 1) ........-0.3V to (V+ + 0.3V)
SCL, SDA, CS, SCLK, DIN, A0, A1 to GND..............-0.3V to +6V
Continuous Current into Any Terminal..............................±20mA
Peak Current (NO_ _, COM_ pulsed at 1ms,
10% duty cycle max) .....................................................±50mA
Continuous Power Dissipation (TA = +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C)............667mW
Operating Temperature Ranges
MAX456_CEE....................................................0°C to +70°C
MAX456_EEE .................................................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
Note 1: Signals on NO_ _ or COM_ exceeding V+ or ground are clamped by internal diodes. Limit forward-diode current to maximum current rating.
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—Single +5V Supply
(V+ = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V+
V
ANALOG SWITCHES
Analog Signal Range (Note 3)
On-Resistance
VNO_ _,
VCOM_
RON
On-Resistance Match
Between Channels (Note 4)
∆RON
On-Resistance
Flatness (Note 5)
RFLAT
NO_ _ Off-Leakage
Current (Note 6)
INO_ _(OFF)
COM_ Off-Leakage
Current (Note 6)
ICOM_(OFF)
COM_ On-Leakage
Current (Note 6)
ICOM_(ON)
0
ICOM_ = 4mA,
VNO_ _ = 3V,
V+ = 4.75V
TA = +25°C
ICOM_ = 4mA,
VNO_ _ = 3V,
V+ = 4.75V
TA = +25°C
20
TA = TMIN to TMAX
30
Ω
40
3
5
Ω
7
TA = TMIN to TMAX
ICOM_ = 4mA;
TA = +25°C
VNO_ _ = 1V, 2V, 3V;
TA = TMIN to TMAX
V+ = 4.75V
2
5
Ω
7
VNO_ _ = 4.5V, 1V;
VCOM_ = 1V, 4.5V;
V+ = 5.25V
TA = +25°C
-1
TA = TMIN to TMAX
-10
VCOM_ = 1V, 4.5V;
VNO_ _ = 4.5V, 1V;
V+ = 5.25V
TA = +25°C
-1
TA = TMIN to TMAX
-10
VCOM_ = 4.5V, 1V;
VNO_ _ = 4.5V, 1V, or
floating; V+ = 5.25V
TA = +25°C
-1
TA = TMIN to TMAX
-10
0.001
1
nA
10
0.001
1
nA
10
0.002
1
nA
10
AUDIO PERFORMANCE
Total Harmonic Distortion
plus Noise
THD+N
Off-Isolation (Note 7)
VISO(A)
fIN = 1kHz, VNO_ _ = RL = 600Ω
1VRMS, VNO_ _ = 2.5V RL =10kΩ
VNO_ _ = 1VRMS, fIN = 20kHz, RL = 600Ω,
Figure 1
Channel-to-Channel Crosstalk
VCT(A)
VNO_ _ = 1VRMS, fIN = 20kHz, RS = 600Ω,
Figure 1
2
0.07
0.006
%
-85
dB
-85
dB
_______________________________________________________________________________________
Serially Controlled, Clickless
Audio/Video Switches
(V+ = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
VIDEO PERFORMANCE
Off-Isolation (Note 7)
VISO(V)
VNO_ _ = 1VRMS, fIN = 10MHz, RL = 50Ω,
Figure 1
-55
dB
Channel-to-Channel Crosstalk
VCT(V)
VNO_ _ = 1VRMS, fIN = 10MHz, RS = 50Ω,
Figure 1
-55
dB
RSOURCE = 50Ω, RL = 50Ω
300
MHz
fIN = 1MHz
10
pF
-3dB Bandwidth
BW
Off-Capacitance
COFF(NO)
DYNAMIC TIMING WITH CLICKLESS MODE DISABLED (Note 8, Figure 2)
Turn-On Time
tONSD
Turn-Off Time
tOFFSD
Break-Before-Make Time
tBBM
VNO_ _ = 2.5V,
RL = 5kΩ,
CL = 35pF
TA = +25°C
VNO_ _ = 2.5V,
RL = 300Ω,
CL = 35pF
TA = +25°C
200
400
ns
TA = TMIN to TMAX
500
100
160
ns
TA = TMIN to TMAX
VNO_ _ = 2.5V, TA = TMIN to TMAX
200
10
50
ns
DYNAMIC TIMING WITH CLICKLESS MODE ENABLED (Note 8, Figure 2)
Turn-On Time
tONSE
VNO_ _ = 2.5V, RL = 5kΩ, CL = 35pF
12
ms
Turn-Off Time
tOFFSE
VNO_ _ = 2.5V, RL = 300Ω, CL = 35pF
3
ms
POWER SUPPLY
Supply Voltage Range
V+
TA = TMIN to TMAX
Supply Current (Note 9)
I+
All logic inputs = 0 or V+, TA = TMIN to TMAX
2.7
5.5
V
6
10
µA
TYP
MAX
UNITS
V+
V
ELECTRICAL CHARACTERISTICS—Single +3V Supply
(V+ = +3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
ANALOG SWITCHES
Analog Signal Range (Note 3)
On-Resistance
VNO_ _,
VCOM_
RON
On-Resistance Match
Between Channels (Note 4)
∆RON
0
ICOM_ = 4mA,
VNO_ _ = 1V,
V+ = 2.7V
TA = +25°C
ICOM_ = 4mA,
VNO_ _ = 1V,
V+ = 2.7V
TA = +25°C
30
TA = TMIN to TMAX
TA = TMIN to TMAX
60
Ω
80
3
5
Ω
7
_______________________________________________________________________________________
3
MAX4562/MAX4563
ELECTRICAL CHARACTERISTICS—Single +5V Supply (continued)
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
ELECTRICAL CHARACTERISTICS—Single +3V Supply (continued)
(V+ = +3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
On-Resistance
Flatness (Note 5)
SYMBOL
RFLAT
NO_ _ Off-Leakage
Current (Notes 6, 10)
INO_ _(OFF)
COM_ Off-Leakage
Current (Notes 6, 10)
ICOM_(OFF)
COM _ On-Leakage
Current (Notes 6, 10)
ICOM_(ON)
CONDITIONS
MIN
ICOM_ = 4mA;
VNO_ _ = 1V, 1.5V, 2V;
V+ = 2.7V
TA = +25°C
VCOM_ = 0.5V, 3V;
VNO_ _ = 3V, 0.5V;
V+ = 3.6V
TA = +25°C
-1
TA = TMIN to TMAX
-10
VCOM_ = 0.5V, 3V;
VNO_ _ = 3V, 0.5V;
V+ = 3.6V
TA = +25°C
-1
TA = TMIN to TMAX
-10
VCOM_ = 3V, 0.5V;
VNO_ _ = 3V, 0.5V,
or floating;
V+ = 3.6V
TA = +25°C
-1
TA = TMIN to TMAX
-10
TYP
MAX
3
6
TA = TMIN to TMAX
UNITS
Ω
8
0.001
1
nA
10
0.001
1
nA
10
0.002
1
nA
10
AUDIO PERFORMANCE
RL = 600Ω
0.1
RL = 10kΩ
0.01
Total Harmonic Distortion
plus Noise
THD+N
fIN = 1kHz, VNO_ _ =
0.5VRMS, VNO_ _ = 1.5V
Off-Isolation (Note 7)
VISO(A)
VNO_ _ = 0.5VRMS, fIN = 20kHz, RL = 600Ω,
Figure 1
80
dB
Channel-to-Channel Crosstalk
VCT(A)
VNO_ _ = 0.5VRMS, fIN = 20kHz, RS = 600Ω,
Figure 1
85
dB
Off-Isolation (Note 7)
VISO(V)
VNO_ _ = 0.5VRMS, fIN = 10MHz, RL = 50Ω,
Figure 1
-50
dB
Channel-to-Channel Crosstalk
VCT(V)
VNO_ _ = 0.5VRMS, fIN = 10MHz, RS = 50Ω,
Figure 1
-55
dB
RSOURCE = 50Ω, RL = 50Ω
200
MHz
fIN = 1MHz
10
pF
%
VIDEO PERFORMANCE
-3dB Bandwidth
BW
Off-Capacitance
COFF(NO)
DYNAMIC TIMING WITH CLICKLESS MODE DISABLED (Notes 8, 12, and Figure 2)
Turn-On Time
tONSD
Turn-Off Time
tOFFSD
Break-Before-Make Time
tBBM
VNO_ _ = 1.5V,
RL = 5kΩ, CL = 35pF
TA = +25°C
400
TA = TMIN to TMAX
TA = +25°C
VNO_ _ = 1.5V,
RL = 300Ω, CL = 35pF TA = TMIN to TMAX
VNO_ _ = 1.5V, TA = TMIN to TMAX
800
1000
200
350
500
10
ns
ns
100
ns
DYNAMIC TIMING WITH CLICKLESS MODE ENABLED (Notes 8, 12, and Figure 2)
Turn-On Time
tONSE
VNO_ _ = 1.5V, RL = 5kΩ, CL = 35pF
12
ms
Turn-Off Time
tOFFSE
VNO_ _ = 1.5V, RL = 300Ω, CL = 35pF
3
ms
4
_______________________________________________________________________________________
Serially Controlled, Clickless
Audio/Video Switches
(V+ = +2.7V to +5.25V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
DIGITAL INPUTS (SCLK, DIN, CS, SCL, SDA, A0, A1)
V+ = 5V
Input Low Voltage
VIL
V+ = 3V
Input High Voltage
VIH
Input Hysteresis
VHYST
Input Leakage Current
ILEAK
Input Capacitance
MAX
UNITS
0.8
V
0.6
V+ = 5V
3
V+ = 3V
2
Digital inputs = 0 or V+
-1
V
0.2
CIN
f = 1MHz
Output Low Voltage
VOL
ISINK = 6mA
DOUT Output High Voltage
VOH
ISOURCE = 0.5mA
0.001
V
1
5
µA
pF
DIGITAL OUTPUTS (DOUT, SDA)
0.4
V
V+ - 0.5
V
2-WIRE TIMING CHARACTERISTICS
(Figure 3, V+ = +2.7V to +5.25V, fSCL = 100kHz, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
SYMBOL
SCL Clock Frequency
fSCL
Bus Free Time between Stop
and Start Conditions
tBUF
CONDITIONS
V+ = 2.7V to 5.25V
MIN
0
V+ = 4.75V to 5.25V
MAX
100
400
UNITS
kHz
4.7
µs
Hold Time After Start Condition
tHD:STA
4.0
µs
Stop Condition Setup Time
tSU:STO
4.0
µs
Data Hold Time
tHD:DAT
0
µs
Data Setup Time
tSU:DAT
250
ns
Clock Low Period
tLOW
4.7
µs
Clock High Period
tHIGH
4.0
µs
SCL/SDA Rise Time
tR
20 +
0.1Cb
300
ns
SCL/SDA Fall Time
tF
20 +
0.1Cb
300
ns
0
50
ns
Pulse Width of Suppressed Spike
The first clock is generated after this period
TYP
_______________________________________________________________________________________
5
MAX4562/MAX4563
I/O INTERFACE CHARACTERISTICS
3-WIRE TIMING CHARACTERISTICS
(Figure 5, V+ = +2.7V to +5.25V, fOP = 2.1MHz, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
SYMBOL
Operating Frequency
CONDITIONS
MIN
V+ = 2.7V to 5.25V
V+ = 4.75V to 5.25V
fOP
TYP
0
MAX
UNITS
2.1
10
MHz
DIN to SCLK Setup
tDS
100
ns
DIN to SCLK Hold
tDH
0
ns
CS Fall to SCLK Rise Setup
tCSS
100
ns
CS Fall to SCLK Rise Hold
tCSH
0
ns
SCLK Pulse Width Low
tCL
200
ns
SCLK Pulse Width High
tCH
200
ns
Rise Time (SCLK, DIN, CS)
tR
2
µs
Fall Time (SCLK, DIN, CS)
tF
2
µs
200
ns
SCLK Fall to Output Data Valid
tDO
CS Pulse Width High
CLOAD = 50pF
tCSW
40
ns
The algebraic convention is used in this data sheet; the most negative value is shown in the minimum column.
Guaranteed by design. Not subject to production testing.
∆RON = RON(MAX) - RON(MIN).
Resistance flatness is defined as the difference between the maximum and minimum on-resistance values, as measured
over the specified analog signal range.
Note 6: Leakage parameters are 100% tested at maximum rated temperature and guaranteed by correlation at TA = +25°C.
Note 7: Off-isolation = 20 log (VCOM_ / VNO_ _ ), VCOM_ = output, VNO_ _ = input to off switch.
Note 8: All timing is measured from the clock’s falling edge preceding the ACK signal for 2-wire and from the rising edge of CS for
3-wire. Turn-off time is defined at the output of the switch for a 0.5V change, tested with a 300Ω load to ground. Turn-on
time is defined at the output of the switch for a 0.5V change and measured with a 5kΩ load resistor to GND. All timing is
shown with respect to 20% V+ and 70% V+, unless otherwise noted.
Note 9: Supply current can be as high as 2mA per switch during switch transitions in the clickless mode, corresponding to a 12mA
total supply transient current requirement.
Note 10: Leakage testing is guaranteed by testing with a +5.25V supply.
Note 11: Cb = capacitance of one bus line in pF. Tested with Cb = 400pF.
Note 12: Typical values are for MAX4563 devices.
Note 2:
Note 3:
Note 4:
Note 5:
Typical Operating Characteristics
(V+ = +5V, TA = +25°C, unless otherwise noted.)
ON-RESISTANCE vs. COM_ VOLTAGE
AND TEMPERATURE
25
23
V+ = 3.3V
21
19
100
TA = +70°C
18
17
TA = +25°C
16
2
3
VCOM_ (V)
COM_ON
NO_ _OFF
1
TA = -40°C
12
1
10
13
15
0
COM_OFF
15
14
V+ = 5.0V
17
6
TA = +85°C
19
ON-RESISTANCE (Ω)
27
20
CURRENT (pA)
V+ = 2.7V
1000
MAX4562 TOC02
29
LEAKAGE CURRENT vs. TEMPERATURE
21
MAX4562 otc01
31
MAX4562/3toc03
ON-RESISTANCE vs. COM_ VOLTAGE
ON-RESISTANCE (Ω)
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
4
5
0.1
0
1
2
3
VCOM_ (V)
4
5
-40
-15
10
35
TEMPERATURE (°C)
_______________________________________________________________________________________
60
85
Serially Controlled, Clickless
Audio/Video Switches
250
TIME (ns)
Q (pC)
0
-1
100
5.2
-2
50
10
35
60
85
0
1
TEMPERATURE (°C)
2
3
4
tOFF, V+ = +5V
-40
5
-15
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
600Ω IN AND OUT
SIGNAL = 1VRMS
35
60
85
VIDEO FREQUENCY RESPONSE
AUDIO FREQUENCY RESPONSE
0
MAX4562 toc07
1
10
TEMPERATURE (°C)
VCOM_ (V)
0
MAX4526 toc08
-15
tOFF, V+ = +3V
0
-3
-40
tON, V+ = +5V
150
5.3
5.1
tON, V+ = +3V
200
1
5.4
MAX4562/3toc06
2
5.5
300
MAX4562 toc05
5.6
SUPPLY CURRENT (µA)
3
MAX4562/3toc04
5.7
TURN-ON AND TURN-OFF TIMES
vs. TEMPERATURE (HARD MODE)
CHARGE INJECTION vs. COM_ VOLTAGE
600Ω IN AND OUT
-20
MAX4562 toc09
SUPPLY CURRENT vs. TEMPERATURE
INSERTION LOSS
-20
0.1
LOSS (dB)
LOSS (dB)
-60
OFF-ISOLATION
-40
OFF-ISOLATION
-60
-80
CROSSTALK
CROSSTALK
-80
-100
50Ω IN AND OUT
0.01
-100
-120
100
1000
10,000
100,000
10
100
1k
10k
100k
0.1
TURN-ON AND TURN-OFF TIMES
(SOFT MODE)
CS
(5V/div)
tON
(1V/div)
1
10
100
FREQUENCY (MHz)
FREQUENCY (Hz)
FREQUENCY (Hz)
TURN-ON AND TURN-OFF TIMES
(HARD MODE)
MAX4562 toc13
10
MAX4562 toc10
THD+N (%)
-40
CS
(5V/div)
tON
(1V/div)
tOFF
(1V/div)
tOFF
(1V/div)
5ms/div
100ns/div
_______________________________________________________________________________________
7
MAX4562/MAX4563
Typical Operating Characteristics (continued)
(V+ = +5V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(V+ = +5V, TA = +25°C, unless otherwise noted.)
SOFT-MODE RISE TIME
AMPLITUDE (500mV/div)
MAX4562 toc12
MAX4562 toc11
SOFT-MODE FALL TIME
AMPLITUDE (500mV/div)
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
500µs/div
500µs/div
Pin Description
PIN
8
NAME
FUNCTION
MAX4562
MAX4563
1
1
V+
2, 4, 6, 8,
10, 12
2, 4, 6, 8,
10, 12
NO1A, NO1B,
NO2A, NO2B,
NO3, NO4
Normally Open Terminals
3, 7, 9, 11
3, 7, 9, 11
COM1–COM4
Common Terminals
5
5
GND
13
–
A1
–
13
DOUT
14
–
A0
LSB + 1 of 2-Wire Serial Interface Address Field
Positive Supply Voltage
Ground
LSB + 2 of 2-Wire Serial Interface Address Field
Data Input of 3-Wire Serial Interface
–
14
CS
Chip-Select of 3-Wire Serial Interface
15
–
SDA
Data Input of 2-Wire Serial Interface
–
15
DIN
Data Input of 3-Wire Serial Interface
16
–
SCL
Clock Input of 2-Wire Serial Interface
–
16
SCLK
Clock Input of 3-Wire Serial Interface
_______________________________________________________________________________________
Serially Controlled, Clickless
Audio/Video Switches
V+
2/3
RL
RL
50Ω
COM2
NO2A
GND
N.C.
2/3
DECODER/
CONTROLLER
SIGNAL
GENERATOR 0dBm
NO_ _
NO1 B
COM1
ANALYZER
DECODER/
CONTROLLER
SIGNAL
GENERATOR 0dBm
V+
10nF
COM_V+
ANALYZER
MAX4562/MAX4563
MAX4562
MAX4563
V+
10nF
GND
a) OFF-ISOLATION
b) CROSSTALK
Figure 1. Off-Isolation and Crosstalk
ACKNOWLEDGE
BIT
3V
MAX4562
MAX4563
0
V+
VOUT
10nF
2-WIRE
0
V+
VNO_ _
2 OR 3
µP
tR < 20ns
tF < 20ns
50%
SCL
NO_ _
-0.5V
tON
VOUT
COM _
VOUT
RL
300Ω
0
VOUT - 0.5V
tOFF
CL
35pF
3V
DECODER/
CONTROLLER
CS
50%
0
SERIAL
INTERFACE
VOUT
0.9 • VOUT
GND
3-WIRE
0
tON
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
VOUT = VCOM [RL / (RL + RON)]
VOUT
0
0.1 • VOUT
tOFF
Figure 2. Switching Time
_______________________________________________________________________________________
9
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
Detailed Description
The MAX4562/MAX4563 are serial-interface controlled
switches with soft-mode “clickless” and hard-mode operating capability. The MAX4562/MAX4563 contain two
SPST switches and two SPDT switches. The SPDT
switches are actually 2-to-1 multiplexers, in that each
SPDT is really two independent SPST switches with a
common node, as shown in the Pin Configuration. Each
switch is controlled independently by either the 2-wire
I2C-compatible or 3-wire SPI/QSPI/MICROWIRE-compatible serial interface.
Audio off-isolation and crosstalk is -85dB at 20kHz.
Video off-isolation and crosstalk is at least -55dB at
10MHz.
Each switch of either device may be set to operate in
either soft or hard mode. In soft mode, the switching
70%
SDA
transition is slowed to avoid the audible “clicking” that
can occur when switches are used to route audio signals. In hard mode, the switches are not slowed down,
making this mode useful when a faster response is
required. If a new command is issued while any softmode switch is transitioning, the switch transition time is
decreased so it reaches its final state before the new
command is executed. Soft mode and open are the
power-up default states for all switches. Switches in the
same mode are guaranteed to be break-before-make
relative to each other. Break-before-make does not apply
between switches operating in different modes.
These devices operate from a +2.7V to +5.5V single
supply. The MAX4562 features a 2-wire I2C-compatible
serial interface, and the MAX4563 features a 3-wire
SPI/QSPI/MICROWIRE-compatible serial interface.
70%
20%
20%
70%
20%
tSU, DAT
70%
20%
70%
20%
tBUF
tSU, STA
tHD, STA
tLOW
70%
20%
SCL
tSU, STO
tHD, DAT
70%
20%
tHIGH
tHD, STA
tR
70%
20%
70%
70%
70%
tF
START CONDITION
REPEATED START CONDITION
STOP CONDITION
Figure 3. 2-Wire Serial-Interface Timing Diagram
COMMAND BYTE
SLAVE ADDRESS BYTE
SDA
MSB
LSB
ACK
MSB
LSB
ACK
SCL
START CONDITION
STOP CONDITION
Figure 4. A Complete 2-Wire Serial-Interface Transmission
10
______________________________________________________________________________________
START CONDITION
Serially Controlled, Clickless
Audio/Video Switches
C1
C0
COMMAND
0
0
NO_OP
No Operation
0
1
NO_OP
No Operation
1
0
SWITCHSET
1
1
MODESET
Table 2. Control-Bit Mapping
CONTROL BIT
SWITCH
SWITCH TERMINAL
D5
SW1A
2, 3
D4
SW1B
3, 4
D3
SW2A
6, 7
D2
SW2B
7, 8
D1
SW3
9, 10
D0 (LSB)
SW4
11, 12
Applications Information
Switch Control
The MAX4562/MAX4563 have a common commandand control-bit structure; the only difference is the interface type (2-wire or 3-wire).
The SWITCHSET command controls the open/closed
states of the various switches. MODESET controls
soft/hard-mode switch states. The NO_OP command is
useful for daisy-chaining multiple 3-wire parts.
Table 1 shows the command bits’ configuration and their
related commands. Table 2 shows the configuration of
the data bits and their related switches. After a SWITCHSET command is issued, a logic “1” in any data-bit location closes the associated switch, while a logic “0”
opens it. After a MODESET command, a logic “1” in any
data-bit location sets the associated switch into soft
mode, while a logic “0” sets it into hard mode.
2-Wire Serial Interface
The MAX4562 uses a 2-wire I2C-compatible serial interface, requiring only two I/O lines of a standard microprocessor port for communication. These devices use
a SendByte™ protocol. The SendByte protocol consists
of one byte of address field followed by one byte of
command field.
The first byte of any 2-wire serial-interface transaction is
always the address byte. To address a given chip, the
DESCRIPTION
Sets specified switches open or closed.
Sets specified switches to soft or hard mode.
A0 and A1 bits in the address byte (Table 3) must duplicate the values present at the A0 and A1 pins of that
chip, and the rest of the address bits must be configured
as shown in Table 3. Connect the A0 and A1 pins to V+
or GND or drive them with CMOS logic levels.
The second byte is the command byte, which sets the
command being written to the device. The possible
commands are MODESET and SWITCHSET. Figures 3
and 4 and the I/O Interface Characteristics detail the timing of the 2-wire serial-interface protocol. All bytes of the
transmission, whether address or command, are sent
MSB first.
The MAX4562/MAX4563 are receive-only devices and
must be controlled by a bus master device. A bus master signals the beginning of a transmission with a start
condition by transitioning SDA from high to low while
SCL is high. The slave devices monitor the serial bus
continuously, waiting for the start condition followed by
an address byte. When a device recognizes its address
byte, it acknowledges by pulling the SDA line low for one
clock period; it is then ready to accept the command
byte. The device also issues a similar acknowledgment
after the command byte. When the master has finished
communicating with the slave, it issues a stop condition
by transitioning SDA from low to high while SCL is high.
The bus is then free for another transmission.
3-Wire Serial Interface
The MAX4563 uses a 3-wire SPI/QSPI/MICROWIRE-compatible serial interface. An active-low chip select (CS) pin
enables the device to receive data from the serial input
pin, DIN. Command and data information are clocked in
on the rising edge of the serial clock signal (SCLK) MSB
first. A total of eight bits is needed in each write cycle.
The command code is contained in the two MSBs of the
8-bit word. The remaining bits control the switches as
shown in Table 4. While shifting in the serial data, the
device remains in its original configuration. A rising edge
on CS latches the data into the MAX4563’s internal register, initiating the device’s change of state. Table 4 shows
the details of the 3-wire interface structure.
SendByte is a trademark of Philips Corp.
______________________________________________________________________________________
11
MAX4562/MAX4563
Table 1. Command-Bit Mapping
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
Table 3. MAX4562 2-Wire Serial-Interface Data Format
ADDRESS BYTE
MSB
SRT
1
0
COMMAND BYTE
LSB
0
1
1
A1
A0
MSB
0
ACK
C1
LSB
C0
SW2A SW1B SW2A SW2B
SW3
SW4
ACK
STP
STP = Stop Condition
Logic “0” in any data bit location places the associated switch open or in hard switching mode.
Logic “1” in any data bit location places the associated switch closed or in soft (clickless) switching mode.
See Table 1 for command-bit configuration.
Table 4. MAX4563 3-Wire Serial-Interface
Data Format
COMMAND
SWITCH CONTROL
MSB
LSB
D7
D6
C1
C0
D5
D4
D3
D2
SW1A SW1B SW2A SW3B
D1
D0
SW3
SW4
Figures 5 and 6 and the I/O Interface Characteristics
show the timing details of the 3-wire interface. If the two
command bits initiate a SWITCHSET command, a logic
“1” in a switch control location closes the associated
switch, while a logic “0” opens it. If the command bits initiate a MODESET command, a logic “1” in a switch control location sets the associated switch into soft
“clickless” mode, while a logic “0” sets it into hard mode.
For command-bit configurations, see Table 1.
Using Multiple Devices
There are two ways to connect multiple devices to the
same 3-wire serial interface. The first involves using the
DOUT pin. DOUT presents a copy of the last bit of the
internal shift register, useful for daisy-chaining multiple
devices. Data at DOUT are simply the input data
delayed by eight clock cycles, appearing synchronous
with SCLK’s falling edge. After CS goes high, DOUT
holds the last bit in the shift register until new data are
shifted into DIN. For a simple interface using several
MAX4563 devices, daisy-chain the shift registers by
connecting DOUT of the first device to DIN of the second, etc. Connect the CS pins of all devices together.
12
Data are shifted through the MAX4563 in series. When
CS is brought high, all devices are updated simultaneously. If any of the devices in the chain are to be left
unchanged, use a NO_OP command for that device, as
shown in Table 1.
An alternate way of connecting multiple devices is to
decode the CS line. In this case, do not use the DOUT
pin and connect the DIN pins of all devices together.
Address decode logic individually controls the CS line
of each device. When a device is to be selected, its CS
line is brought low, data are shifted in, and its CS line is
then brought high to execute the command.
For command bit configuration see Table 1.
T-Switches
Configure the MAX4562/MAX4563 as a T-switch to
improve off-isolation. As the signal frequency is increased, parasitic capacitance significantly degrades
the off-isolation. Figure 7 shows a typical T-switch configuration using the MAX4562/MAX4563 to improve offisolation. COM2 and COM3 are tied together to create
a single common node. NO2A and NO2B act as the
input and output of the T-switch, while NO3 is tied to
ground. When both SW2A and SW2B are closed, SW3
should be open to allow the signal to pass into NO2A
and out of NO2B. However, when SW2A and SW2B are
open, energy that is coupled through the open switches is shunted to ground through SW3, which should
now be closed. This increases the off-isolation to typically -68dB at 10MHz (Figure 8).
______________________________________________________________________________________
Serially Controlled, Clickless
Audio/Video Switches
20%
70%
tCSW
tCSH
SCLK
20%
tDH
20%
tCSO
tCH
tCL
tCSS
MAX4562/MAX4563
20%
CS
20% 20%
70%
70%
70%
20%
tDS
D6
D7
DIN
D1
D0
tDO
DOUT
Figure 5. 3-Wire Serial-Interface Timing Diagram
SWITCHES UPDATED
CS
-20
SCLK
-40
OFF-ISOLATION (dB)
DATA CLOCKED IN
DIN
D7
D6 D5 D4 D3 D2 D1 D0
LSB
MSB
SPST
SWITCH
-60
-80
T-SWITCH
-100
INPUT DATA BITS
DATA CLOCKED OUT
-120
DOUT
0.1
D7
D6 D5 D4 D3 D2 D1 D0
D7
1
10
100
FREQUENCY (MHz)
DATA BITS FROM PREVIOUS DATA INPUT
DOUT POWER-UP DEFAULT: D7–D0 = 0
Figure 8. Off-Isolation vs. Frequency
Figure 6. A Complete 3-Wire Serial-Interface Transmission
___________________Chip Information
SIGNAL IN
NO2A
COM2
NO2B
TRANSISTOR COUNT: 3518
SIGNAL OUT
COM3
NO3
Figure 7. T-Switch Configuration
______________________________________________________________________________________
13
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
QSOP.EPS
Package Information
14
______________________________________________________________________________________
Serially Controlled, Clickless
Audio/Video Switches
______________________________________________________________________________________
MAX4562/MAX4563
NOTES
15
MAX4562/MAX4563
Serially Controlled, Clickless
Audio/Video Switches
NOTES
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1999 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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