19-5929; Rev 1; 6/12
EVALUATION KIT AVAILABLE
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
General Description
The MAX14778 dual 4:1 analog multiplexer supports
analog signals up to Q25V with a single 3.0 to 5.5V
supply. Each multiplexer has separate control inputs to
allow independent switching, making the device ideal for
multiplexing different communications signals with the
same connector pins. Extended ESD protection of Q6kV
(Human Body Model) enable direct interfacing to cables
and connectors.
The MAX14778 features a low 1.5I (max) on-resistance
and 3mI (typ) flatness to maximize signal integrity over
the entire common-mode voltage range. Each multiplexer can carry up to 300mA of continuous current through
the multiplexer in either direction.
The MAX14778 supports switching of full-speed USB 1.1
signals (12Mbps) and RS-485 data rates of up to 20Mbps.
The MAX14778 is available in a 20-pin (5mm x 5mm)
TQFN package and is specified over the -40NC to +85NC
extended temperature range.
Features
S ±25V Signal Range
S Single 3.0V to 5.5V Supply
S Two Independent Multiplexers
S 1.5I RON (max)
S 3mI RON Flatness (typ)
S 300mA Maximum Current Through Multiplexer
S 78pF Input Capacitance
S 75MHz Large-Signal Bandwidth
S Break-Before-Make Operation
S Extended ESD Protection on A_ and B_ Pins
 Q6kV Human Body Model (HBM)
Ordering Information appears at end of data sheet.
For related parts and recommended products to use with this part,
refer to www.maxim-ic.com/MAX14778.related.
Functional Diagram
Applications
RS-485/RS-232/USB 1.1 Multiplexing
POS Peripherals
ENA
SA0
SA1
VDD
Handheld Industrial Devices
Communication Systems
CONTROL A
BIAS
GENERATION
VP
VN
Audio/Data Multiplexing
Connector Sharing
A0
Gaming Machines
A1
MAX14778
ACOM
A2
A3
B0
B1
BCOM
B2
B3
CONTROL B
ENB
SB0
SB1
GND
����������������������������������������������������������������� 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.
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND.)
VDD...........................................................................-0.3V to +6V
VP............................ -0.3V to the lesser of +52V and (VN + 70V)
VN................. The lesser of (VDD - 40V) and (VP - 70V) to +0.3V
VP to VN..................................................................-0.3V to +70V
ENA, ENB, SA_, SB_................................. -0.3V to (VDD + 0.3V)
A_, ACOM, B_,
BCOM... (VN - 0.3V) to the lesser of (VP + 0.3V) and (VN + 52V)
Continuous Current Through Switch.............................. ±500mA
Continuous Power Dissipation (TA = +70NC)
TQFN (derate 33.3mW/NC above +70NC)...............2666.7mW
Operating Temperature Range........................... -40NC to +85NC
Junction Temperature......................................................+150NC
Storage Temperature Range............................. -65NC to +150NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow).......................................+260NC
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.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
TQFN
Junction-to-Ambient Thermal Resistance (BJA)...........30NC/W
Junction-to-Case Thermal Resistance (BJC)..................2NC/W
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(VDD = 3.0V to 5.5V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VDD = 5V, TA = +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
5.5
V
DC CHARACTERISTICS
Supply Voltage Range
VDD
3.0
ENA = ENB = high
Supply Current
IDD
VENA = VENB = VDD/2
Charge-Pump Threshold
Analog Signal Range
VDDTH
VIN
Continuous Current
Through Switch
ICOM
On-Resistance
RON
On-Resistance Flatness
RFLAT(ON)
VDD P VDDTH
4.27
10
VDD > VDDTH
2.54
6
VDD P VDDTH
4.31
10
VDD > VDDTH
2.59
6
(Note 3)
Figure 1, switch open or closed
4.64
mA
V
-25
+25
V
-300
+300
mA
1.5
Ω
0.84
Figure 1, ICOM = Q300mA, VIN = Q25V
Figure 1, -25V P VIN P +25V,
ICOM = Q300mA
3
mΩ
A_, B_ Off-Leakage
Current
IA(OFF),
IB(OFF)
Figure 2, VIN = 25V, VOUT = 0V
-200
+200
nA
ACOM, BCOM
Off-Leakage Current
IACOM(OFF),
IBCOM(OFF)
Figure 2, VOUT = 15V, VIN = 0V
-1
+1
FA
A_, B_ On-Leakage
Current
IA(ON),
IB(ON)
Figure 2, VIN = Q25V, ACOM or BCOM
is unconnected
-1
+1
FA
����������������������������������������������������������������� Maxim Integrated Products 2
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 3.0V to 5.5V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VDD = 5V, TA = +25NC.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
LOGIC INPUTS (ENA, ENB, SA_, SB_)
Input Logic-Low Voltage
VIL
VDD = 5.5V
0.8
VDD = 4.5V
0.8
VDD = 3.6V
0.7
VDD = 3.0V
Input Logic-High Voltage
VIH
V
0.7
VDD = 5.5V
2.1
VDD = 4.5V
2.0
VDD = 3.6V
1.9
VDD = 3.0V
1.7
V
AC CHARACTERISTICS
Power-Up Time
tPOR
404
ms
Enable Turn-On Time
tON
Figure 3, VIN = Q10V, RL = 10kI,
CL = 15pF
Enable Turn-Off Time
tOFF
Figure 3, VIN = Q10V, RL = 10kI,
CL = 15pF
Break-Before-Make
Interval
tBBM
Figure 4, VIN = Q10V, RL = 10kI,
CL = 15pF
840
Fs
Figure 5, VA_ = 0V, CL = 1nF
Charge Injection
Q
Off-Isolation
VISO
Figure 6, VA_ = 1VRMS, f = 100kHz,
RL = 50I, CL = 15pF
Crosstalk
VCT
Figure 6, f = 100kHz, RS = RL = 50I
-3dB Bandwidth
BW
Figure 6, RS = 50I, RL = 50I
Total Harmonic Distortion
Plus Noise
Input Capacitance
THD+N
CIN
RS = RL = 1kI, f = 20Hz to 20kHz
A_, B_ pins
2
ms
1.5
ms
1720
pC
-80
dB
-103
dB
75
MHz
0.003
%
78
pF
THERMAL PROTECTION
Thermal-Shutdown
Threshold
TSHUT
145
NC
Thermal-Shutdown
Hysteresis
THYST
25
NC
ESD PROTECTION
A_, B_ Pins (Note 4)
Human Body Model
Q6
kV
All Other Pins
Human Body Model
Q2
kV
Note 2: All units are production tested at TA = +25NC. Specifications over temperature are guaranteed by design.
Note 3: When VDD is higher than the charge-pump threshold, the internal 5V regulated charge pump is turned off and the input to
the high-voltage charge pumps is provided by VDD.
Note 4: The MAX14778 requires a 100nF capacitor on both VP and VN to GND to guarantee full ESD protection. See the
Applications Information section for details on ESD test conditions.
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MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Test Circuits/Timing Diagrams
V
+5V
1µF
VDD
MAX14778
A_
B_
VIN
ACOM
BCOM
ICOM
GND
Figure 1. On-Resistance Measurement
+5V
+5V
1µF
1µF
VDD
IA(OFF)
IB(OFF)
A
VIN
VDD
MAX14778
A_
B_
ACOM
BCOM
GND
IACOM(OFF)
IBCOM(OFF)
IA(ON)
IB(ON)
A
A
VOUT
VIN
MAX14778
A_
B_
ACOM
BCOM
GND
Figure 2. Leakage Current Measurement
����������������������������������������������������������������� Maxim Integrated Products 4
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Test Circuits/Timing Diagrams (continued)
LOGIC
INPUT
MAX14778
VIN
A_
B_
ACOM
BCOM
t R < 20ns
t F < 20ns
VIH
VIL
50%
VOUT
RL
t OFF
CL
ENA
VOUT
ENB
SWITCH
OUTPUT
LOGIC
INPUT
0.9 x V0UT
0.1 x VOUT
0V
t ON
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
RL
VOUT = VIN R + R
L
ON
(
)
Figure 3. Turn-On/Turn-Off Timing
+5V
1µF
+5V
VDD
SA0
ENA
SA1
tR < 20ns
MAX14778
0V
LOGIC
INPUT
LOGIC
INPUT
VOUT
A_
ACOM
VIN
GND
VOUT
RL
80%
SWITCH
OUTPUT
CL
0V
tBBM
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
RL
VOUT = VIN R + R
L
ON
(
)
Figure 4. Break-Before-Make Timing
����������������������������������������������������������������� Maxim Integrated Products 5
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Test Circuits/Timing Diagrams (continued)
+5V
+5V
A_
B_
VDD
LOGIC
INPUT
OFF
LOGIC
INPUT
OFF
0V
MAX14778
ACOM
BCOM
ENA
ENB
ON
VOUT
C L = 1nF
GND
DVOUT
VOUT
Q = CL x DVOUT
Figure 5. Charge Injection
VDD
OFF-ISOLATION = 20log
NETWORK
ANALYZER
0V OR VDD
ENA
SA_
50I
A0
50I
VIN
V
ON-LOSS = 20log OUT
VIN
50I
MAX14778
ACOM
VOUT
MEAS
50I
VOUT
VIN
REF
V
CROSSTALK = 20log OUT
VIN
50I
MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS.
OFF-ISOLATION IS MEASURED BETWEEN ACOM AND "OFF" A_ TERMINAL ON EACH MULTIPLEXER.
-3dBW IS MEASURED BETWEEN ACOM AND "ON" A_ TERMINAL ON EACH MULTIPLEXER.
CROSSTALK IS MEASURED FROM ONE CHANNEL TO ALL OTHER CHANNELS.
SIGNAL DIRECTION THROUGH MULTIPLEXER IS REVERSED; WORST VALUES ARE RECORDED.
Figure 6. Off-Isolation, -3dB Bandwidth, and Crosstalk
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MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Typical Operating Characteristics
(VDD = 5.0V, TA = +25°C, unless otherwise noted.)
0.97
VDD = 5V
0.96
1.1
TA = +85°C
1.0
0.9
TA = +25°C
0.8
0.7
0.6
IACOM = 300mA
0.95
-5
5
15
0.5
25
-15
-5
CHARGE INJECTION
vs. ANALOG SIGNAL VOLTAGE
MAX14778 toc04
-40
1,000
35
60
600
3.0
VDD = 3.3V
2.5
2.0
VDD = 5V
0.5
CL = 1nF
0
-25
85
-15
-5
5
15
0
-40
25
-15
10
OFF-ISOLATION vs. FREQUENCY
-80
-100
A0 TO ACOM
A2 SELECTED
-2
-30
-40
-50
FREQUENCY (MHz)
100
-3
-4
-5
-6
-7
-8
A0 TO ACOM
A0 SELECTED
-9
-70
10
0
-1
-20
-60
-120
85
FREQUENCY RESPONSE
VOUT / VIN (dB)
OFF-ISOLATION (dB)
-60
60
1
MAX14778 toc08
MAX14778 toc07
0
-10
35
TA (°C)
VACOM (V)
-40
1
85
1.0
200
CROSSTALK vs. FREQUENCY
0.1
60
3.5
1.5
TA (°C)
A0 TO B0
A0 AND B0 SELECTED
35
4.0
IDD (mA)
Q (pC)
10
10
SUPPLY CURRENT vs. TEMPERATURE
1,200
VA0 = 25V
A0 SELECTED
ACOM UNCONNECTED
-15
-15
TA (°C)
400
-40
CROSSTALK (dB)
25
800
1
-20
15
ON-LEAKAGE CURRENT
vs. TEMPERATURE
10
0
5
VACOM (V)
100
VA1 = 25V
A0 SELECTED
ACOM = GND
0.1
-25
VACOM (V)
1000
1
MAX14778 toc09
-15
10
TA = -40°C
IACOM = 300mA
MAX14778 toc05
-25
ON-LEAKAGE CURRENT (nA)
1.2
MAX14778 toc06
0.98
MAX14778 toc03
1.3
100
OFF-LEAKAGE CURRENT (nA)
1.4
ON-RESISTANCE (I)
VDD = 3.3V
MAX14778 toc02
0.99
ON-RESISTANCE (I)
1.5
MAX14778 toc01
1.00
OFF-LEAKAGE CURRENT
vs. TEMPERATURE
ON-RESISTANCE
vs. COMMON-MODE VOLTAGE
ON-RESISTANCE
vs. COMMON-MODE VOLTAGE
-10
0.1
1
10
FREQUENCY (MHz)
100
0.1
1
10
100
FREQUENCY (MHz)
����������������������������������������������������������������� Maxim Integrated Products 7
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Typical Operating Characteristics (continued)
(VDD = 5.0V, TA = +25°C, unless otherwise noted.)
MAX14778 toc10
A0 TO ACOM
RS = 600I
RL = 1kI
VDD TO ACOM
-20
-40
PSRR (dB)
THD+N (%)
0.1
PSRR vs. FREQUENCY
0
MAX14778 toc11
THD+N vs. FREQUENCY
1
0.01
-60
-80
-100
0.001
-120
0.0001
-140
0.2
0.02
2
20
10
100
TURN-ON TIME
vs. ANALOG-SIGNAL VOLTAGE
TURN-OFF TIME
vs. ANALOG-SIGNAL VOLTAGE
1.16
0.45
0.40
0.35
1.12
0.30
tOFF (ms)
1.14
1.10
1.08
MAX14778 toc13
0.50
MAX14778 toc12
1.18
0.25
0.20
1.06
0.15
1.04
0.10
1.02
0.05
1.00
0
-15
-25
-5
5
15
25
15
CHARGE PUMP NOISE WITH
SWITCH DISABLED
25
MAX14778 toc14
0
MEASURED AT BCOM
ENB = GND
RBW = 5100Hz
-20
-40
MAG (dB)
-60
5
CHARGE PUMP NOISE WITH
SWITCH ENABLED
MEASURED AT BCOM
ENB = VDD
BS0 = BS1 = VDD
B2 IS CONNECTED TO GND
WITH A 50I RESISTOR
RBW = 5100Hz
-40
-5
VACOM (V)
0
-20
-15
-25
VACOM (V)
MAX14778 toc15
tON (ms)
1
FREQUENCY (kHz)
1.20
MAG (dB)
0.1
0.01
FREQUENCY (kHz)
-80
-60
-80
-100
-100
-120
-120
-140
-140
20
30
40
50 60 70
FREQ (MHz)
80
90
100
20
30
40
50 60 70
FREQ (MHz)
80
90
100
����������������������������������������������������������������� Maxim Integrated Products 8
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
SB1
VDD
SA1
SA0
TOP VIEW
SB0
Pin Configuration
15
14
13
12
11
ENB 16
10
ENA
B3 17
9
A3
8
A2
7
A1
6
A0
B2 18
MAX14778
B1 19
*EP
*CONNECT EXPOSED PAD TO VN.
2
3
4
5
VN
ACOM
BCOM
1
GND
+
VP
B0 20
TQFN
5mm x 5mm
Pin Description
PIN
NAME
1
BCOM
FUNCTION
MUX B Common Terminal
2
VP
3
GND
Positive Charge-Pump Output. Bypass VP to GND with a 100nF 50V ceramic capacitor.
4
VN
5
ACOM
6
A0
MUX A Bidirectional Analog Input/Output 0
7
A1
MUX A Bidirectional Analog Input/Output 1
8
A2
MUX A Bidirectional Analog Input/Output 2
9
A3
MUX A Bidirectional Analog Input/Output 3
10
ENA
MUX A Enable Input
11
SA0
MUX A Channel Select Input 0
12
SA1
MUX A Channel Select Input 1
13
VDD
Power-Supply Input. Bypass VDD to GND with a 1FF ceramic capacitor.
14
SB1
MUX B Channel Select Input 1
15
SB0
MUX B Channel Select Input 0
16
ENB
MUX B Enable Input
17
B3
MUX B Bidirectional Analog Input/Output 3
18
B2
MUX B Bidirectional Analog Input/Output 2
19
B1
MUX B Bidirectional Analog Input/Output 1
20
B0
MUX B Bidirectional Analog Input/Output 0
—
EP
Exposed Pad. Connect EP to VN. EP is not intended as an electrical connection point.
Ground
Negative Charge-Pump Output. Bypass VN to GND with a 100nF 50V ceramic capacitor.
MUX A Common Terminal
����������������������������������������������������������������� Maxim Integrated Products 9
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Truth Tables
Table 1. MUX A Channel Selection
Table 2. MUX B Channel Selection
ENA
SA1
SA0
ACOM
CONNECTED TO
ENB
SB1
SB0
BCOM
CONNECTED TO
0
X
X
Open
0
X
X
Open
1
0
0
A0
1
0
0
B0
1
0
1
A1
1
0
1
B1
1
1
0
A2
1
1
0
B2
1
1
1
A3
1
1
1
B3
X = Don’t care
X = Don’t care
Detailed Description
The MAX14778 dual 4:1 analog multiplexer integrates
bias circuitry to provide a Q25V analog voltage range
with a single 3.0 to 5.5V supply. This extended input
range allows multiplexing different communications
signals such as RS-232, RS-485, audio and USB 1.1 onto
the same connector.
Integrated Bias Generation
The MAX14778 contains a total of three charge pumps to
generate bias voltages for the internal switches: a 5V regulated charge pump, a positive high-voltage (+35V) charge
pump, and a negative high-voltage (-27V) charge pump.
When VDD is above 4.7V (typ), the 5V regulated charge
pump is bypassed and VDD provides the input for the highvoltage charge pumps, reducing overall supply current.
An external 100nF capacitor is required for each highvoltage charge pump between VP/VN and GND.
Analog Signal Levels
The MAX14778 transmits signals of up to Q25V with a
single 3.0 to 5.5V supply due to integrated bias circuitry.
The device features 1.5Ω (max) on-resistance and 3mI
(typ) flatness for analog signals between -25V and +25V
(see the Typical Operating Characteristics). The current
flow through the multiplexers can be bidirectional, allowing operation either as a multiplexer or demultiplexer.
Digital Interface
The MAX14778 has two digital select inputs for each
MUX: SA1 and SA0 control MUX A; SB1 and SB0 control
MUX B. Drive the digital select inputs high or low to select
which input (A_, B_) is connected to the common terminal (ACOM, BCOM) for each MUX. See the Truth Tables
for more information.
Each MUX features an independent enable input (ENA
and ENB). Drive ENA or ENB low to disconnect all inputs
from the common terminal for that MUX, regardless of the
status of the select inputs or the other enable input.
Applications Information
Connector Sharing
The MAX14778 supports a Q25V analog signal range
independently for each input/output, allowing physical
connector sharing between interface types that have
differing signal ranges.
The multiprotocol connector-sharing application in the
Typical Operating Circuits shows an application with
RS-232, half-duplex RS-485, full-speed USB 1.1, and
audio signals sharing the same connector. The device
allows signals to pass over the entire signal range specified by each standard while safely isolating the unused
transceivers.
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MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Non-Powered Condition
The MAX14778 can tolerate input voltages on the A_, B_,
ACOM, and BCOM pins in the ±25V range when it is not
powered.
When VDD = 0V, the DC input leakage current into the
A_, B_, ACOM or BCOM pins will typically be below 1µA.
Some devices can have a larger leakage current up to
mA range due to technology spread.
With VDD not powered, internal diodes between the analog pins and the VP and VN will charge up the external
capacitors on VP and VN when positive and/or negative
voltages are applied to these pins. This causes transient
input current flow.
Large dv/dt on the inputs causes large capacitive charging currents, which have to be limited to the 300mA
Absolute Maximum Ratings in order to not destroy the
internal diodes. With 100nF capacitors on VP and VN, the
dv/dt must be limited to 3V/µs once the capacitors reach
their final voltage; the input current decays to the leakage
current levels mentioned above.
RC
1MI
CHARGE CURRENTLIMIT RESISTOR
RD
1.5kI
High-ESD Protection
Electrostatic discharge (ESD)-protection structures are
incorporated on all pins to protect against electrostatic
discharges up to Q2kV Human Body Model (HBM)
encountered during handling and assembly. A_ and B_
are further protected against ESD up to Q6kV (HBM)
without damage. The ESD structures withstand high ESD
both in normal operation and when the device is powered
down. After an ESD event, the MAX14778 continues to
function without latchup.
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents test
setup, test methodology, and test results.
The MAX14778 requires a 100nF capacitor on both VP
and VN to GND to guarantee full ESD protection.
Human Body Model
Figure 7 shows the Human Body Model. Figure 8 shows
the current waveform it generates when discharged
into a low impedance. This model consists of a 100pF
capacitor charged to the ESD voltage of interest that is
then discharged into the device through a 1.5kI resistor.
IP 100%
90%
DISCHARGE
RESISTANCE
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPERES
HIGHVOLTAGE
DC
SOURCE
CS
100pF
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
36.8%
10%
0
0
tRL
TIME
tDL
CURRENT WAVEFORM
Figure 7. Human Body ESD Test Model
Figure 8. Human Body Current Waveform
���������������������������������������������������������������� Maxim Integrated Products 11
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Typical Operating Circuits
+5V
1µF
VDD
VP
RS-232
TRANSCEIVER
TX
A0
RX
B0
A
A1
B
B1
D+
A2
D-
B2
L
A3
R
B3
MAX14778
VN
100nF
100nF
SHARED
CONNECTOR
+5V
ACOM
RS-485
TRANSCEIVER
USB 1.1
TRANSCEIVER
AUDIO
SOURCE
BCOM
CONTROL
ENA
MULTIPROTOCOL CONNECTOR
SHARING APPLICATION
SA1
SA0
SB1
SB0
ENB
GND
CONTROL
INPUTS
���������������������������������������������������������������� Maxim Integrated Products 12
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Typical Operating Circuits (continued)
+5V
1µF
VDD
VP
RS-232
TRANSCEIVER
TX
A0
RX
B0
A
A1
B
B1
D+
A2
D-
B2
CLOCK
A3
DATA
B3
MAX14778
VN
100nF
100nF
SHARED
CONNECTOR
+5V
ACOM
RS-485
TRANSCEIVER
USB 1.1
TRANSCEIVER
KEYBOARD
WEDGE
BCOM
CONTROL
ENA
SCANNER CONNECTOR
SHARING APPLICATION
SA1
SA0
SB1
SB0
ENB
GND
CONTROL
INPUTS
���������������������������������������������������������������� Maxim Integrated Products 13
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX14778ETP+
-40NC to +85NC
20 TQFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Chip Information
PROCESS: BiCMOS
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
20 TQFN-EP
T2055+4
21-0140
90-0009
���������������������������������������������������������������� Maxim Integrated Products 14
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Revision History
REVISION
NUMBER
REVISION
DATE
0
6/11
Initial release
1
6/12
Added new TOCs 14 and 15, updated Non-Powered Condition section, updated
Note 4, Pin Description, ESD Test Conditions, Typical Operating Circuits, updated
capacitor values
DESCRIPTION
PAGES
CHANGED
—
3, 8, 9, 10, 11,
12, 13
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. The parametric values (min and max limits) shown in the Electrical
Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
©
2012 Maxim Integrated Products
15
Maxim is a registered trademark of Maxim Integrated Products, Inc.