EVALUATION KIT AVAILABLE
19-5929; Rev 1; 6/12
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.
Applications
RS-485/RS-232/USB 1.1 Multiplexing
POS Peripherals
Handheld Industrial Devices
Communication Systems
Audio/Data Multiplexing
Connector Sharing
Gaming Machines
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
SA0ENA
SA1 V
CONTROL A
A0
A1
A2
DD
BIAS
GENERATION
MAX14778
V
P
V
N
ACOM
A3
B0
B1
B2
B3
CONTROL B
SB0ENB SB1
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GND
BCOM
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)
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 four-
layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
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
ELECTRICAL CHARACTERISTICS
(VDD = 3.0V to 5.5V, T
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
DC CHARACTERISTICS
Supply Voltage Range V
Supply Current I
Charge-Pump Threshold V
Analog Signal Range V
Continuous Current
Through Switch
On-Resistance R
On-Resistance Flatness R
A_, B_ Off-Leakage
Current
ACOM, BCOM
Off-Leakage Current
A_, B_ On-Leakage
Current
= -40NC to +85NC, unless otherwise noted. Typical values are at VDD = 5V, T
A
DD
DD
DDTH
IN
I
COM
ON
FLAT(ON)
I
A(OFF)
I
B(OFF)
I
ACOM(OFF)
I
BCOM(OFF)
I
A(ON)
I
B(ON)
ENA = ENB = high
V
= V
ENA
(Note 3) 4.64 V
Figure 1, switch open or closed -25 +25 V
Figure 1, I
Figure 1, -25V P VIN P +25V,
I
= Q300mA
COM
,
Figure 2, VIN = 25V, V
,
Figure 2, V
,
Figure 2, VIN = Q25V, ACOM or BCOM
is unconnected
= VDD/2
ENB
= Q300mA, VIN = Q25V
COM
= 15V, VIN = 0V -1 +1
OUT
VDD P V
VDD > V
VDD P V
VDD > V
OUT
DDTH
DDTH
DDTH
DDTH
= 0V -200 +200 nA
3.0 5.5 V
-300 +300 mA
-1 +1
= +25NC.) (Note 2)
A
4.27 10
2.54 6
4.31 10
2.59 6
0.84 1.5 Ω
3 mΩ
mA
FA
FA
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MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 3.0V to 5.5V, T
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
LOGIC INPUTS (ENA, ENB, SA�, SB�)
Input Logic-Low Voltage V
Input Logic-High Voltage V
AC CHARACTERISTICS
Power-Up Time t
Enable Turn-On Time t
Enable Turn-Off Time t
Break-Before-Make
Interval
Charge Injection Q Figure 5, VA_ = 0V, CL = 1nF 1720 pC
Off-Isolation V
Crosstalk V
= -40NC to +85NC, unless otherwise noted. Typical values are at VDD = 5V, T
A
VDD = 5.5V 0.8
VDD = 4.5V 0.8
VDD = 3.6V 0.7
VDD = 3.0V 0.7
VDD = 5.5V 2.1
VDD = 4.5V 2.0
VDD = 3.6V 1.9
VDD = 3.0V 1.7
Figure 3, VIN = Q10V, RL = 10kI,
CL = 15pF
Figure 3, VIN = Q10V, RL = 10kI,
CL = 15pF
Figure 4, VIN = Q10V, RL = 10kI,
CL = 15pF
Figure 6, VA_ = 1V
RL = 50I, CL = 15pF
Figure 6, f = 100kHz, RS = RL = 50I
, f = 100kHz,
RMS
POR
ON
OFF
t
BBM
ISO
IL
IH
CT
= +25NC.) (Note 2)
A
404 ms
2 ms
1.5 ms
840
-80 dB
-103 dB
V
V
Fs
-3dB Bandwidth BW
Total Harmonic Distortion
Plus Noise
Input Capacitance C
THERMAL PROTECTION
Thermal-Shutdown
Threshold
Thermal-Shutdown
Hysteresis
ESD PROTECTION
A_, B_ Pins (Note 4) Human Body Model
All Other Pins Human Body Model
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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THD+N
IN
T
SHUT
T
HYST
Figure 6, RS = 50I, RL = 50I
RS = RL = 1kI, f = 20Hz to 20kHz
A_, B_ pins 78 pF
75 MHz
0.003 %
145
25
Q6
Q2
NC
NC
kV
kV
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Test Circuits/Timing Diagrams
V
+5V
1µF
V
DD
MAX14778
A_
B_
ACOM
BCOM
Figure 1. On-Resistance Measurement
I
A(OFF)
I
B(OFF)
A
V
IN
MAX14778
A_
B_
+5V
V
GND
V
IN
1µF
DD
I
ACOM(OFF)
I
BCOM(OFF)
ACOM
BCOM
A
GND
V
OUT
I
COM
+5V
1µF
V
DD
I
A(ON)
I
B(ON)
A
V
IN
MAX14778
A_
B_
ACOM
BCOM
GND
Figure 2. Leakage Current Measurement
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MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Test Circuits/Timing Diagrams (continued)
MAX14778
A_
V
IN
B_
ENA
LOGIC
INPUT
ENB
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
V
= V
(
OUT
IN
RL + R
Figure 3. Turn-On/Turn-Off Timing
SA0
ENA
MAX14778
SA1
LOGIC
INPUT
A_
V
IN
RL
+5V
V
DD
GND
ON
ACOM
BCOM
)
1µF
ACOM
t
OFF
80%
tR < 20ns
tF < 20ns
0.1 x V
t
BBM
OUT
V
IH
LOGIC
INPUT
V
V
OUT
R
C
L
R
L
SWITCH
OUTPUT
LOGIC
INPUT
V
C
L
L
OUT
SWITCH
OUTPUT
IL
0V
+5V
0V
V
OUT
0V
V
t
50%
OUT
ON
0.9 x V
tR < 20ns
0UT
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
V
OUT
= V
RL
(
IN
RL + R
Figure 4. Break-Before-Make Timing
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ON
)
LOGIC
INPUT
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Test Circuits/Timing Diagrams (continued)
+5V
A_
B_
ENA
ENB
V
DD
MAX14778
GND
ACOM
BCOM
V
OUT
C
= 1nF
L
LOGIC
INPUT
+5V
ON OFFOFF
0V
DV
V
OUT
OUT
Figure 5. Charge Injection
0V OR V
DD
ENA
SA_
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.
V
DD
MAX14778
ACOM
Q = CL x DV
NETWORK
ANALYZER
50
V
A0
IN
V
OUT
I
MEAS REF
50I
I
50
50I
OFF-ISOLATION = 20log
ON-LOSS = 20log
CROSSTALK = 20log
OUT
V
OUT
V
IN
V
OUT
V
IN
V
OUT
V
IN
Figure 6. Off-Isolation, -3dB Bandwidth, and Crosstalk
����������������������������������������������������������������� Maxim Integrated Products 6
Dual ±25V Above- and Below-the-Rails
(VDD = 5.0V, TA = +25°C, unless otherwise noted.)
ON-RESISTANCE
1.00
0.99
0.98
0.97
ON-RESISTANCE (I)
0.96
0.95
1000
ON-LEAKAGE CURRENT (nA)
vs. COMMON-MODE VOLTAGE
VDD = 3.3V
VDD = 5V
I
= 300mA
ACOM
-25 25
V
(V)
ACOM
155-5-15
ON-LEAKAGE CURRENT
vs. TEMPERATURE
100
10
VA0 = 25V
A0 SELECTED
1
-40 85
ACOM UNCONNECTED
603510-15
TA (°C)
MAX14778 toc01
MAX14778 toc04
ON-RESISTANCE (I)
1,200
1,000
Q (pC)
4:1 Analog Multiplexer
Typical Operating Characteristics
ON-RESISTANCE
vs. COMMON-MODE VOLTAGE
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
I
ACOM
0.5
-25 25
vs. ANALOG SIGNAL VOLTAGE
800
600
400
200
0
-25 25
TA = +85°C
TA = +25°C
= 300mA
V
ACOM
CHARGE INJECTION
V
ACOM
TA = -40°C
(V)
(V)
155-5-15
CL = 1nF
155-5-15
100
MAX14778 toc02
10
1
OFF-LEAKAGE CURRENT (nA)
0.1
-40 85
SUPPLY CURRENT vs. TEMPERATURE
4.0
3.5
MAX14778 toc05
3.0
2.5
(mA)
2.0
DD
I
1.5
1.0
0.5
0
-40 85
MAX14778
OFF-LEAKAGE CURRENT
vs. TEMPERATURE
MAX14778 toc03
VA1 = 25V
A0 SELECTED
ACOM = GND
603510-15
TA (°C)
MAX14778 toc06
VDD = 3.3V
VDD = 5V
6035-15 10
TA (°C)
CROSSTALK vs. FREQUENCY
0
A0 TO B0
A0 AND B0 SELECTED
-20
-40
-60
CROSSTALK (dB)
-80
-100
-120
0.1 100
FREQUENCY (MHz)
101
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MAX14778 toc07
OFF-ISOLATION (dB)
OFF-ISOLATION vs. FREQUENCY
0
A0 TO ACOM
A2 SELECTED
-10
-20
-30
-40
-50
-60
-70
0.1 100
FREQUENCY (MHz)
101
MAX14778 toc08
1
FREQUENCY RESPONSE
0
-1
-2
-3
(dB)
IN
-4
/V
-5
OUT
V
-6
-7
-8
A0 TO ACOM
-9
A0 SELECTED
-10
0.1 100
FREQUENCY (MHz)
101
MAX14778 toc09
Dual ±25V Above- and Below-the-Rails
(VDD = 5.0V, TA = +25°C, unless otherwise noted.)
MAX14778
4:1 Analog Multiplexer
Typical Operating Characteristics (continued)
1
A0 TO ACOM
R
= 600I
S
= 1kI
R
L
0.1
0.01
THD+N (%)
0.001
0.0001
0.02 20
FREQUENCY (kHz)
20.2
TURN-ON TIME
vs. ANALOG-SIGNAL VOLTAGE
THD+N vs. FREQUENCY
1.20
1.18
1.16
1.14
1.12
(ms)
1.10
ON
t
1.08
1.06
1.04
1.02
1.00
-25 25
V
(V)
ACOM
CHARGE PUMP NOISE WITH
SWITCH ENABLED
0
MEASURED AT BCOM
ENB = VDD
-20
BS0 = BS1 = VDD
B2 IS CONNECTED TO GND
-40
WITH A 50I RESISTOR
RBW = 5100Hz
-60
MAG (dB)
-80
0
VDD TO ACOM
MAX14778 toc10
-20
-40
-60
PSRR (dB)
-80
-100
-120
-140
0.01 100
FREQUENCY (kHz)
MAX14778 toc11
1010.1
TURN-OFF TIME
vs. ANALOG-SIGNAL VOLTAGE
PSRR vs. FREQUENCY
0.50
0.45
MAX14778 toc12
155-5-15
0.40
0.35
0.30
(ms)
0.25
OFF
t
0.20
0.15
0.10
0.05
0
-25 25
V
(V)
ACOM
155-5-15
MAX14778 toc13
CHARGE PUMP NOISE WITH
SWITCH DISABLED
0
MEASURED AT BCOM
ENB = GND
MAX14778 toc14
-20
-40
-60
MAG (dB)
-80
RBW = 5100Hz
MAX14778 toc15
-100
-120
-140
20 100
FREQ (MHz)
90807060504030
-100
-120
-140
20 100
FREQ (MHz)
90807060504030
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MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Pin Configuration
TOP VIEW
ENB
SB0
15 14 12 11
16
B3
17
18
B1
19
20
B0
+
12B245
BCOM
DD
SB1
V
13
MAX14778
3
P
V
GND
SA1
V
SA0
ENA
10
A3
9
8
A2
A1
7
A0
*EP
N
6
ACOM
TQFN
5mm x 5mm
*CONNECT EXPOSED PAD TO V
.
N
Pin Description
PIN NAME FUNCTION
1 BCOM MUX B Common Terminal
2 V
P
3 GND Ground
4 V
N
5 ACOM MUX A Common Terminal
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 V
DD
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.
Positive Charge-Pump Output. Bypass VP to GND with a 100nF 50V ceramic capacitor.
Negative Charge-Pump Output. Bypass VN to GND with a 100nF 50V ceramic capacitor.
Power-Supply Input. Bypass VDD to GND with a 1FF ceramic capacitor.
����������������������������������������������������������������� 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
0 X X Open
1 0 0 A0
1 0 1 A1
1 1 0 A2
1 1 1 A3
X = Don’t care
ACOM
CONNECTED TO
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.
ENB SB1 SB0
0 X X Open
1 0 0 B0
1 0 1 B1
1 1 0 B2
1 1 1 B3
X = Don’t care
BCOM
CONNECTED TO
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.
���������������������������������������������������������������� Maxim Integrated Products 10
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.
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 V
P
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.
R
C
1MI
CHARGE CURRENT-
LIMIT RESISTOR
HIGH-
VOLTAGE
DC
SOURCE
Figure 7. Human Body ESD Test Model Figure 8. Human Body Current Waveform
C
S
100pF
���������������������������������������������������������������� Maxim Integrated Products 11
R
D
1.5kI
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
AMPERES
IP 100%
90%
36.8%
10%
I
r
0
0
t
RL
TIME
t
DL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
RS-232
TRANSCEIVER
RS-485
TRANSCEIVER
USB 1.1
TRANSCEIVER
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Typical Operating Circuits
+5V
1µF
V
DD
V
P
A0TX
RX
B0
A
A1
B
B1
D+
A2
D-
B2
MAX14778
ACOM
V
N
100nF
100nF
SHARED
CONNECTOR
+5V
A3
L
AUDIO
SOURCE
MULTIPROTOCOL CONNECTOR
SHARING APPLICATION
B3
R
CONTROL
SA1ENA SA0 SB1 SB0 ENB
CONTROL
INPUTS
BCOM
GND
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RS-232
TRANSCEIVER
RS-485
TRANSCEIVER
USB 1.1
TRANSCEIVER
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Typical Operating Circuits (continued)
+5V
1µF
V
DD
V
P
A0TX
RX
B0
A
A1
B
B1
D+
A2
D-
B2
MAX14778
ACOM
V
N
100nF
100nF
SHARED
CONNECTOR
+5V
CLOCK
KEYBOARD
WEDGE
SCANNER CONNECTOR
SHARING APPLICATION
DATA
A3
B3
CONTROL
SA1ENA SA0 SB1 SB0 ENB
CONTROL
INPUTS
BCOM
GND
���������������������������������������������������������������� Maxim Integrated Products 13
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Ordering Information
PART TEMP RANGE PIN-PACKAGE
MAX14778ETP+
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
-40NC to +85NC
20 TQFN-EP*
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
20 TQFN-EP T2055+4
PACKAGE
CODE
OUTLINE
NO.
21-0140 90-0009
LAND
PATTERN NO.
���������������������������������������������������������������� Maxim Integrated Products 14
MAX14778
Dual ±25V Above- and Below-the-Rails
4:1 Analog Multiplexer
Revision History
REVISION
NUMBER
0 6/11 Initial release —
1 6/12
REVISION
DATE
DESCRIPTION
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
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 15
©
2012 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
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