MAX4529CSA [MAXIM]
Low-Voltage, Bidirectional RF/Video Switch; 低电压，双向RF /视频开关
| 型号： | MAX4529CSA |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Low-Voltage, Bidirectional RF/Video Switch |
| 文件： | 总12页 (文件大小：125K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-1262; Rev 0; 3/98
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
MAX4529
Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
♦ High 50Ω Off Isolation: -80dB at 10MHz
♦ DC to 300MHz -3dB Signal Bandwidth
♦ 70Ω Signal Paths with ±5V Supplies
The MAX4529 is a low-voltage T-switch designed for
switching RF and video signals from DC to 300MHz in
50Ω and 75Ω systems. This switch is constructed in a
“T” configuration, ensuring excellent high-frequency off
isolation of -80dB at 10MHz.
♦ 10Ω Signal-Path Flatness with ±5V Supplies
®
The MAX4529 can handle Rail-to-Rail analog signals
♦ ±2.7V to ±6V Dual Supplies
in either direction. On-resistance (70Ω max) is flat (0.5Ω
max) over the specified signal range, using ±5V sup-
plies. The off leakage current is less than 1nA at +25°C
and 20nA at +85°C.
+2.7V to +12V Single Supply
♦ Low Power Consumption: <1µW
♦ Rail-to-Rail Bidirectional Signal Handling
♦ >2kV ESD Protection per Method 3015.7
This CMOS switch can operate with dual power sup-
plies ranging from ±2.7V to ±6V or a single supply
b e twe e n + 2.7V a nd + 12V. All d ig ita l inp uts ha ve
0.8V/2.4V logic thresholds, ensuring both TTL- and
CMOS-logic compatibility when using ±5V or a single
+5V supply.
♦ TTL/CMOS-Compatible Inputs with
Single +5V or ±5V
Ord e rin g In fo rm a t io n
PIN-
PACKAGE
SOT
TOP MARK
PART
TEMP. RANGE
________________________Ap p lic a t io n s
MAX4529CPA
MAX4529CSA
MAX4529CUA
MAX4529CUT-T
MAX4529C/D
MAX4529EPA
MAX4529ESA
MAX4529EUA
0°C to +70°C 8 Plastic DIP
0°C to +70°C 8 Narrow SO
0°C to +70°C 8 µMAX
—
—
RF Switching
Video Signal Routing
High-Speed Data Acquisition
Test Equipment
—
0°C to +70°C 6 SOT23-6
0°C to +70°C Dice*
AAAQ
—
-40°C to +85°C 8 Plastic DIP
-40°C to +85°C 8 Narrow SO
-40°C to +85°C 8 µMAX
—
ATE Equipment
—
Networking
—
MAX4529EUT-T -40°C to +85°C 6 SOT23-6
*Contact factory for dice specifications.
AAAQ
_______________________P in Co n fig u ra t io n s /Fu n c t io n a l Dia g ra m s /Tru t h Ta b le
MAX4529
MAX4529
1
2
3
4
8
7
6
5
1
2
3
6
5
4
N.C.
NC
V+
NC
V+
V-
COM
GND
IN
LOGIC
SWITCH
COM
N.C.
V-
0
1
ON
OFF
GND
IN
SOT23-6
DIP/SO/µMAX
N.C. = NOT INTERNALLY CONNECTED
Rail-to-Rail is a registered trademark of Nippon Motorola Ltd.
________________________________________________________________ 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 408-737-7600 ext. 3468.
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
ABSOLUTE MAXIMUM RATINGS
(Voltages referenced to GND)
Continuous Power Dissipation (T = +70°C)
A
V+ ...........................................................................-0.3V, +13.0V
V- ............................................................................-13.0V, +0.3V
V+ to V-...................................................................-0.3V, +13.0V
All Other Pins (Note 1)..........................(V- - 0.3V) to (V+ + 0.3V)
Continuous Current into Any Terminal..............................±10mA
Peak Current into Any Terminal
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) ...727mW
8-Pin SO (derate 5.88mW/°C above +70°C)............... 471mW
8-Pin µMAX (derate 4.1mW/°C above +70°C)............. 330mW
6-Pin SOT23-6 (derate 7.1mW/°C above +70°C) ........571mW
Operating Temperature Ranges
MAX4529C_ E.....................................................0°C to +70°C
MAX4529E_ E ..................................................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
(pulsed at 1ms, 10% duty cycle)..................................±50mA
ESD per Method 3015.7 ..................................................>2000V
MAX4529
Note 1: Voltages on all other pins exceeding V+ or V- 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—Dual Supplies
(V+ = +4.5V to +5.5V, V- = -4.5V to -5.5V, V
= 0.8V, V
= 2.4V, V
= 0V, T = T
to T , unless otherwise noted. Typical
MAX
GND
INL
INH
A
MIN
values are at T = +25°C.)
A
MIN
TYP
(Note 2)
MAX
PARAMETER
SYMBOL
CONDITIONS
T
A
UNITS
ANALOG SWITCH
Analog Signal Range
V
, V
(Note 3)
V+ = 5V, V- = -5V,
= ±3V, I
C, E
V-
V+
70
V
COM NC
+25°C
C, E
45
Signal-Path On-Resistance
R
Ω
ON
V
= 1mA
COM
COM
100
Signal-Path On-Resistance
Flatness (Note 4)
V+ = 5V; V- = -5V; V
= 3V,
COM
R
+25°C
5
10
Ω
FLAT(ON)
0V, -3V; I
= 1mA
COM
+25°C
C, E
-1
-20
-1
0.02
1
20
1
NC Off Leakage Current
(Notes 5, 6)
V+ = 5.5V, V- = -5.5V,
I
±
±
nA
nA
nA
NC(OFF)
V
COM
= ±4.5V, V
=
4.5V
NC
+25°C
C, E
0.02
0.02
COM Off Leakage Current
(Notes 5, 6)
V+ = 5.5V, V- = -5.5V,
= ±4.5V, V
I
COM(OFF)
V
COM
=
NC
4.5V
-20
-2
20
2
+25°C
C, E
COM On Leakage Current
(Notes 5, 6)
V+ = 5.5V, V- = -5.5V,
I
COM(ON)
V
COM
= ±4.5V
-40
40
LOGIC INPUT
IN Input Logic Threshold High
IN Input Logic Threshold Low
V
C, E
C, E
1.5
1.5
2.4
1
V
V
INH
V
INL
0.8
-1
IN Input Current Logic High or
Low
I
, I
V
IN
= 0.8V or 2.4V
C, E
0.03
µA
INH INL
2
_______________________________________________________________________________________
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
MAX4529
ELECTRICAL CHARACTERISTICS—Dual Supplies (continued)
(V+ = +4.5V to +5.5V, V- = -4.5V to -5.5V, V
= 0.8V, V
= 2.4V, V
= 0V, T = T
to T
, unless otherwise noted. Typical
MAX
GND
INL
INH
A
MIN
values are at T = +25°C.)
A
MIN
TYP
(Note 2)
MAX
PARAMETER
SYMBOL
CONDITIONS
T
A
UNITS
SWITCH DYNAMIC CHARACTERISTICS
+25°C
C, E
45
37
75
100
75
V
= ±3V, V+ = 5V, V- = -5V,
COM
Turn-On Time
t
ns
ns
ON
Figure 2
+25°C
C, E
V
= ±3V, V+ = 5V, V- = -5V,
COM
Turn-Off Time
t
OFF
Figure 2
100
C
= 1.0nF, V = 0V, R = 0Ω,
L
NC
S
Charge Injection (Note 3)
Q
+25°C
5
10
pC
Figure 3
NC Off Capacitance
C
V
= GND, f = 1MHz, Figure 5
+25°C
+25°C
6
6
pF
pF
NC(OFF)
NC
COM_ Off Capacitance
C
V
COM
= 0V, f = 1MHz, Figure 5
COM(OFF)
V
= V = 0V, f = 1MHz,
NC
COM
COM_ On Capacitance
C
+25°C
11.5
pF
COM(ON)
Figure 5
R
= 50Ω, V
= 1V
,
L
COM
RMS
Off Isolation (Note 7)
-3dB Bandwidth
Distortion
V
+25°C
+25°C
+25°C
-80
300
dB
MHz
%
ISO
f = 10MHz, Figure 4
R = 50Ω, Figure 4
L
BW
V
= 5Vp-p, f < 20kHz,
IN
THD+N
0.004
600Ω in and out
POWER SUPPLY
Power-Supply Range
V+, V-
I+
C, E
+25°C
C, E
±2.7
-1
±6
1
V
0.05
0.05
V+ = 5.5V, V = 0V or V+,
IN
V- = -5.5V
V+ Supply Current
V - Supply Current
µA
-10
-1
10
1
+25°C
C, E
V+ = 5.5V, V = 0V or V+,
IN
V- = -5.5V
I-
µA
-10
10
_______________________________________________________________________________________
3
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
ELECTRICAL CHARACTERISTICS—Single +5V Supply
(V+ = +4.5V to +5.5V, V- = 0V, V
= 0.8V, V
= 2.4V, V
= 0V, T = T
to T
, unless otherwise noted. Typical values are
MAX
GND
INL
INH
A
MIN
at T = +25°C.)
A
MIN
TYP
(Note 2)
MAX
PARAMETER
SYMBOL
CONDITIONS
T
UNITS
A
ANALOG SWITCH
Analog Signal Range
V
, V
(Note 3)
V+ = 5V, V = 3V,
COM
+25°C
+25°C
C, E
0
V+
120
150
1
V
COM NC
70
5
Signal-Path On-Resistance
R
Ω
ON
I
= 1mA
COM
+25°C
C, E
-1
-20
-1
0.02
0.02
0.02
NC Off Leakage Current
(Notes 5, 6, 8)
V+ = 5.5V, V
= 1V,
COM
I
nA
nA
nA
NC(OFF)
V
NC
= 4.5V
20
1
+25°C
C, E
COM Off Leakage Current
(Notes 5, 6, 8)
V+ = 5.5V, V
= 1V,
COM
I
COM(OFF)
V
NC
= 4.5V
-20
-2
20
2
+25°C
C, E
COM On Leakage Current
(Notes 5, 6, 8)
I
V+ = 5.5V; V
= 1V, 4.5V
COM(ON)
COM
-40
40
LOGIC INPUT
IN Input Logic Threshold High
IN Input Logic Threshold Low
V
C, E
C, E
1.5
1.5
2.4
1
V
V
INH
V
INL
0.8
-1
IN Input Current Logic High or
Low
I
, I
V
IN
= 0.8V or 2.4V
C, E
0.03
µA
INH INL
SWITCH DYNAMIC CHARACTERISTICS
+25°C
C, E
65
43
100
120
90
V
= 3V, V+ = 5V,
COM
Turn-On Time (Note 3)
Turn-Off Time (Note 3)
Charge Injection (Note 3)
Off-Isolation (Note 7)
t
ns
ns
ON
Figure 2
+25°C
C, E
V
= 3V, V+ = 5V,
COM
t
OFF
Q
Figure 2
110
C
L
R
S
= 1.0nF, V = 2.5V,
NC
= 0Ω, Figure 3
+25°C
+25°C
1.5
-75
10
pC
dB
R
= 50Ω, V
= 1V
,
L
COM
RMS
V
ISO
f = 10MHz, Figure 4
POWER SUPPLY
Power-Supply Range
V+
I+
V- = 0V
C, E
+25°C
C, E
2.7
-1
12.0
1
V
0.05
V+ Supply Current
V+ = 5.5V, V = 0V or V+
µA
IN
-10
10
4
_______________________________________________________________________________________
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
MAX4529
ELECTRICAL CHARACTERISTICS—Single +3V Supply
(V+ = +2.7V to +3.6V, V- = 0V, V
= 0.4V, V
= 2.4V, V
= 0V, T = T
to T
, unless otherwise noted. Typical values are
MAX
GND
INL
INH
A
MIN
at T = +25°C.)
A
MIN
TYP
(Note 2)
MAX
PARAMETER
SYMBOL
CONDITIONS
T
A
UNITS
ANALOG SWITCH
Analog Signal Range
V
, V
(Note 3)
V+ = 2.7V, V
+25°C
+25°C
C, E
0
V+
V
COM NC
175
400
500
= 1.5V,
COM
Signal-Path On-Resistance
R
Ω
ON
I
= 0.1mA
COM
LOGIC INPUT
IN Input Logic Threshold High
IN Input Logic Threshold Low
IN Input Current Logic High or Low
V
(Note 3)
(Note 3)
C, E
C, E
C, E
1.0
1.0
2.4
1
V
V
INH
V
INL
0.4
-1
I
, I
V
= 0.4V or 2.4V (Note 3)
µA
INH INL
IN
SWITCH DYNAMIC CHARACTERISTICS
+25°C
C, E
150
70
300
400
150
200
V
= 1.5V, V+ = 2.7V,
COM
Turn-On Time
t
ns
ns
ON
Figure 2 (Note 3)
+25°C
C, E
V
= 1.5V, V+ = 2.7V,
COM
Turn-Off Time
t
OFF
Figure 2 (Note 3)
POWER SUPPLY
V+ Supply Current
+25°C
C, E
-1
0.05
1
I+
V+ = 3.6V, V = 0V or V+
µA
IN
-10
10
Note 2: The algebraic convention is used in this data sheet; the most negative value is shown in the minimum column.
Note 3: Guaranteed by design.
Note 4: Resistance flatness is defined as the difference between the maximum and the minimum value of on-resistance as
measured over the specified analog signal range.
Note 5: Leakage parameters are 100% tested at the maximum rated hot temperature and guaranteed by correlation at +25°C.
Note 6: Guaranteed by design, not subject to production testing in SOT package.
Note 7: Off isolation = 20log (V
/ V ), V
= output, V = input to off switch.
COM NC
10 COM
NC
Note 8: Leakage testing for single-supply operation is guaranteed by testing with dual supplies.
__________________________________________Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s
(V+ = +5V, V- = -5V, GND = 0V, T = +25°C, packages are surface mount, unless otherwise noted.)
A
ON-RESISTANCE vs. V
ON-RESISTANCE vs. V
ON-RESISTANCE vs. V
AND
COM
COM
COM
(DUAL SUPPLIES)
(SINGLE SUPPLY)
TEMPERATURE (DUAL SUPPLIES)
1000
100
1000
100
70
60
50
40
30
20
10
0
V- = 0V
V+ = 1.2V
V+ = 2.0V
+125°C
+85°C
V+ = 1.2V
V- = -1.2V
V+ = 2.0V
V- = -2.0V
V+ = 2.7V
V+ = 3.3V
V+ = 5.0V
V+ = 2.7V
V- = -2.7V
+70°C +25°C
0°C
-40°C
-55°C
V+ = 7.5V
V+ = 3.3V
V- = -3.3V
V+ = 5.0V
V- = -5.0V
V+ = 10.0V
V+ = 5V
V- = -5V
10
10
-5 -4 -3 -2 -1
0
1
2
3
4
5
0
1
2
3
4
5
6
7
8
9
10
-5 -4 -3 -2 -1
0
1
2
3
4
5
V
COM
(V)
V
COM
(V)
V
COM
(V)
_______________________________________________________________________________________
5
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
____________________________Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s (c o n t in u e d )
(V+ = +5V, V- = -5V, GND = 0V, T = +25°C, packages are surface mount, unless otherwise noted.)
A
ON-RESISTANCE vs. V
AND
SUPPLY, COM, AND NC
COM
TEMPERATURE (SINGLE SUPPLY)
LEAKAGE CURRENTS vs. TEMPERATURE
CHARGE INJECTION vs. V
COM
1,000,000
100,000
10,000
1000
100
70
60
50
40
30
20
10
0
15
12
9
V+ = 5V
V- = -5V
+125°C
+85°C
I+, I-
MAX4529
V+ = 5V
V- = -5V
+70°C
+25°C
I
ON
V+ = 5V
V- = 0V
0°C
6
10
-40°C
-55°C
1
V+ = 3V
V- = 0V
I
OFF
3
0.1
V+ = 5V
V- = -5V
0.01
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
(V)
-55 -35 -15
5
25 45 65 85 105 125
-5 -4 -3 -2 -1
0
1
2
3
4
5
V
TEMPERATURE (°C)
V
(V)
COM
COM
LOGIC-LEVEL THRESHOLD
vs. SUPPLY VOLTAGE
OFF-TIME vs. TEMPERATURE
ON-TIME vs. TEMPERATURE
80
70
60
50
40
30
20
10
0
3.0
2.5
2.0
1.5
1.0
0.5
0
180
160
140
120
100
80
V+ = 3V
V- = 0V
V+ = 3V
V- = 0V
V+ = 5V
V- = 0V
V+ = 5V
V- = 0V
V+ = 5V
V- = -5V
60
40
V+ = 5V
V- = -5V
20
0
-55 -35 -15
5
25 45 65 85 105 125
0
1
2
3
4
5
6
7 8 9 10 11 12
-55 -35 -15
5
25 45 65 85 105 125
TEMPERATURE (°C)
V+ (V)
TEMPERATURE (°C)
TOTAL HARMONIC DISTORTION
vs. FREQUENCY
FREQUENCY RESPONSE
MAX4529-10
100
0
-10
60
ON LOSS
50
-20
40
-30
30
-40
20
10
1
-50
10
-60
0
ON PHASE
-70
-10
-20
-30
-40
-50
-80
-90
-100
-110
-120
OFF ISOLATION
0.1
-60
10
100
1k
10k 30k
0.1
1
10
100
1000
FREQUENCY (Hz)
FREQUENCY (MHz)
6
_______________________________________________________________________________________
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
MAX4529
P in De s c rip t io n
PIN
DIP/SO/µMAX
NAME
FUNCTION*
SOT23-6
—
1
1, 6
2
N.C.
NC
Not Internally Connected
Analog Switch Normally Closed** Terminal
Positive Supply-Voltage Input (analog and digital). The voltage difference between
V+ and V- should never exceed 12V.
2
8
V+
3
4
5
5
4
3
V-
IN
-5V Supply Input. Connect to GND for single-supply operation.
Logic-Level Control Input. Logic-level voltages should never exceed V+ or V-.
RF and Logic Ground. Connect to ground plane.
GND
Analog Switch Common** Terminal. Analog signal voltages should never exceed
V+ or V-.
6
7
COM
*
All pins except N.C. have ESD diodes to V- and V+.
** NC and COM pins are identical and interchangeable. Either may be considered as an input or output; signals pass equally well in
either direction.
Th e o ry o f Op e ra t io n
NORMALLY CLOSED SWITCH CONSTRUCTION
Lo g ic -Le ve l Tra n s la t o rs
N1
N2
COM
IN
NC
D
S
D
S
The MAX4529 is constructed as a high-frequency “T”
switch, as shown in Figure 1. The logic-level input, IN,
is translated by amplifier A1 into a V+ to V- logic signal
that drives inverter A2. Amplifier A2 drives the gates of
N-channel MOSFETs N1 and N2 from V+ to V-, turning
them fully on or off. The same signal drives inverter A3
(which drives the P-channel MOSFETs P1 and P2) from
V+ to V-, turning them fully on or off, and drives the N-
channel MOSFET N3 off and on.
COM - NC
P1
P2
0
1
ON
OFF
S
D
S
D
V+
IN
D
A1
A2
A3
N3
S
GND
V-
V+
The log ic -le ve l thre s hold is d e te rmine d b y V+ a nd
GND. The voltage on GND is usually at ground poten-
tia l, b ut it ma y b e s e t to a ny volta g e b e twe e n
(V+ - 2V) and V-. When the voltage between V+ and
GND is less than 2V, the level translators become very
slow and unreliable. Normally, GND should be connect-
ed to the ground plane.
ESD DIODES
ON GND, IN,
COM, AND NC
V-
Figure 1. T-Switch Construction
tances are distributed evenly along the series resis-
tance, so they act as a transmission line rather than a
simple R-C filter. This helps to explain the exceptional
300MHz bandwidth when the switches are on.
S w it c h On Co n d it io n
When the switch is on, MOSFETs N1, N2, P1, and P2
are on and MOSFET N3 is off. The signal path is COM to
NC, a nd b e c a us e b oth N-c ha nne l a nd P-c ha nne l
MOSFETs act as pure resistances, it is symmetrical (i.e.,
signals may pass in either direction). The off MOSFET,
N3, has no DC conduction, but has a small amount of
capacitance to GND. The four on MOSFETs also have
capacitance to ground that, together with the series
resistance, forms a lowpass filter. All of these capaci-
Typical attenuation in 50Ω systems is -2dB and is rea-
sonably flat up to 100MHz. Higher-impedance circuits
s how e ve n lowe r a tte nua tion (a nd vic e ve rs a ), b ut
slightly lower bandwidth due to the increased effect of
the internal and external capacitance and the switch’s
internal resistance.
_______________________________________________________________________________________
7
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
The MAX4529 is a optimized for ±5V operation. Using
lower supply voltages or a single supply increases
switching time, on-resistance (and therefore on-state
attenuation), and nonlinearity.
switched V+ and V- signals to drive the gates of the
analog switches. This drive signal is the only connec-
tion between the logic supplies and the analog sup-
plies. All pins have ESD protection to V+ and to V-.
Increasing V- has no effect on the logic-level thresh-
olds, but it does increase the drive to the P-channel
switches, reducing their on-resistance. V- also sets the
negative limit of the analog signal voltage.
S w it c h Off Co n d it io n
When the switch is off, MOSFETs N1, N2, P1, and P2
a re off a nd MOSFET N3 is on. The s ig na l p a th is
through the off-capacitances of the series MOSFETs,
but it is shunted to ground by N3. This forms a high-
pass filter whose exact characteristics depend on the
source and load impedances. In 50Ω systems, and
below 10MHz, the attenuation can exceed 80dB. This
va lue d e c re a s e s with inc re a s ing fre q ue nc y a nd
increasing circuit impedances. External capacitance
and board layout have a major role in determining over-
all performance.
5
The logic-level thresholds are CMOS and TTL compati-
ble when V+ is +5V. As V+ is raised, the threshold
increases slightly; when V+ reaches +12V, the level
threshold is about 3.1V, which is above the TTL output
high-level minimum of 2.8V, but still compatible with
CMOS outputs.
Bipolar-Supply Operation
The MAX4529 operates with bipolar supplies between
±2.7V and ±6V. The V+ and V- supplies need not be
symmetrical, but their sum cannot exceed the absolute
ma ximum ra ting of 13.0V. Do not connect the
MAX4529 V+ pin to +3V and connect the logic-level
input pins to TTL logic-level signals. TTL logic-level
outputs can exceed the absolute maximum ratings,
causing damage to the part and/or external circuits.
Ap p lic a t io n s In fo rm a t io n
P o w e r-S u p p ly Co n s id e ra t io n s
Overview
The MAX4529’s construction is typical of most CMOS
analog switches. It has three supply pins: V+, V-, and
GND. V+ and V- are used to drive the internal CMOS
switches and set the limits of the analog voltage on any
switch. Reverse ESD protection diodes are internally
connected between each analog signal pin and both
V+ and V-. If the voltage on any pin exceeds V+ or V-,
one of these diodes will conduct. During normal opera-
tion these reverse-biased ESD diodes leak, forming the
only current drawn from V-.
CAUTION:
The absolute maximum V+ to V- differential
voltage is 13.0V. Typical “±6-Volt” or “12-Volt”
supplies with ±10% tolerances can be as high
as 13.2V. This voltage can damage the
MAX4529. Even ±5% tolerance supplies may
have overshoot or noise spikes that exceed
13.0V.
Virtually all the analog leakage current is through the
ESD diodes. Although the ESD diodes on a given sig-
nal pin are identical, and therefore fairly well balanced,
they are reverse biased differently. Each is biased by
either V+ or V- and the analog signal. This means their
leakages vary as the signal varies. The difference in the
two diode leakages from the signal path to the V+ and
V- pins constitutes the analog signal-path leakage cur-
rent. All analog leakage current flows to the supply ter-
minals, not to the other switch terminal. This explains
how both sides of a given switch can show leakage
currents of either the same or opposite polarity.
Single-Supply Operation
The MAX4529 operates from a single supply between
+2.7V and +12V when V- is connected to GND. All of
the bipolar precautions must be observed. Note, how-
ever, that these parts are optimized for ±5V operation,
and most AC and DC characteristics are degraded sig-
nificantly when departing from ±5V. As the overall sup-
ply voltage (V+ to V-) is lowered, switching speed,
on-resistance, off isolation, and distortion are degraded
(see Typical Operating Characteristics).
When the switch is on, there is no connection between
the analog signal paths and GND. The analog signal
paths consist of an N-channel and P-channel MOSFET
with their sources and drains paralleled and their gates
driven out of phase with V+ and V- by the logic-level
translators.
Single-supply operation also limits signal levels and
interferes with grounded signals. When V- = 0V, AC sig-
nals are limited to -0.3V. Voltages below -0.3V can be
clipped by the internal ESD-protection diodes, and the
parts can be damaged if excessive current flows.
V+ and GND power the internal logic and logic-level
translators, and set the input logic thresholds. The
log ic -le ve l tra ns la tors c onve rt the log ic le ve ls to
8
_______________________________________________________________________________________
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
MAX4529
Single-Supply Operation Above 5V
AC Ground and Bypassing
A ground plane is mandatory for satisfactory high-
frequency operation. (Prototyping using hand wiring
or wire-wrap boards is strongly discouraged.) Connect
any 0V GND pins to the ground plane with solid cop-
per. (The GND pin extends the high-frequency ground
through the package wire-frame, into the silicon itself,
thus improving isolation.) The ground plane should be
solid metal underneath the device, without interrup-
tions. There should be no traces under the device itself.
For DIP packages, this applies to both sides of a two-
sided board. Failure to observe this will have a minimal
effect on the “on” characteristics of the switch at high
frequencies, but it will degrade the off isolation and
crosstalk.
The MAX4529 is designed for operation from single
+5V or dual ±5V supplies. As V+ is increased above
5V, the logic-level threshold voltage increases and the
supply current increases. In addition, if the logic levels
are not driven rail-to-rail, the analog signal pins, COM
and NC, can conduct a significant DC current (up to
1mA) to the s up p ly p ins . This c urre nt c a n a d d a n
unwanted DC bias to the signal. Therefore, when oper-
ating V+ above 5V, always drive the IN pin rail-to-rail.
Power Off
When power to the MAX4529 is off (i.e., V+ = 0V and V-
= 0V), the Absolute Maximum Ratings still apply. This
means that neither logic-level inputs on IN nor signals
on COM or NC can exceed ±0.3V. Voltages beyond
±0.3V cause the internal ESD-protection diodes to con-
duct, and the parts can be damaged if excessive cur-
rent flows.
V+ and V- pins should be bypassed to the ground
plane with surface-mount 10nF capacitors. For DIP
packages, they should be mounted as close as possi-
ble to the pins on the same side of the board as the
device. Do not use feedthroughs or vias for bypass
capacitors. For surface-mount packages, the pins are
s o c los e to e a c h othe r tha t the b yp a s s c a p a c itors
should be mounted on the opposite side of the board
from the device. In this case, use short feedthroughs or
vias, directly under the V+ and V- pins. Any GND pin
not connected to 0V should be similarly bypassed. If V-
is 0V, connect it directly to the ground plane with solid
copper. Keep all leads short.
Gro u n d in g
DC Ground Considerations
Satisfactory high-frequency operation requires that
careful consideration be given to grounding. For most
applications, a ground plane is strongly recom-
mended, and GND should be connected to it with
solid copper.
In systems that have separate digital and analog (sig-
nal) grounds, connect these switch GND pins to analog
ground. Preserving a good signal ground is much more
important than preserving a digital ground. Ground cur-
rent is only a few nanoamps.
S ig n a l Ro u t in g
Keep all signal leads as short as possible. Separate all
signal leads from each other and other traces with the
ground plane on both sides of the board. Where possi-
ble, use coaxial cable instead of printed circuit board
traces.
The logic-level input, IN, has voltage thresholds deter-
mine d b y V+ a nd GND. (V- d oe s not influe nc e the
logic-level threshold.) With +5V and 0V applied to V+
and GND, the threshold is about 1.6V, ensuring com-
patibility with TTL- and CMOS-logic drivers.
Bo a rd La yo u t
IC sockets degrade high-frequency performance and
should not be used if signal bandwidth exceeds 5MHz.
Surfa c e -mount p a rts , ha ving s horte r inte rna l le a d
frames, provide the best high-frequency performance.
Keep all bypass capacitors close to the device, and
separate all signal leads with ground planes. Such
grounds tend to be wedge-shaped as they get closer to
the device. Use vias to connect the ground planes on
each side of the board, and place the vias in the apex of
the wedge-shaped grounds that separate signal leads.
Logic-level signal lead placement is not critical.
The GND pin can be connected to separate voltage
potentials if the logic-level input is not a normal logic
signal. (The GND voltage cannot exceed (V+ - 2V) or V-.)
Elevating GND reduces off isolation. Note, however,
that IN can be driven more negative than GND, as far
as V-. GND does not have to be removed from 0V when
IN is driven from bipolar sources, but the voltage on IN
should never exceed V-. GND should be separated
from 0V only if the log ic -le ve l thre s hold ha s to b e
changed.
If the GND pin is not connected to 0V, it should be
bypassed to the ground plane with a surface-mount
10nF capacitor to maintain good RF grounding. DC
current in the IN and GND pins is less than 1nA, but
increases with switching frequency.
_______________________________________________________________________________________
9
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
______________________________________________Te s t Circ u it s /Tim in g Dia g ra m s
+5V
10nF
V+
0V
V+
V
IN
50%
50%
NC
3V
MAX4529
MAX4529
90%
V
IN
V
OUT
IN
COM
V
OUT
90%
GND
V-
0V
R = 50Ω
L
t
t
ON
50Ω
OFF
10nF
-5V
V- IS CONNECTED TO GND (OV) FOR SINGLE-SUPPLY OPERATION.
Figure 2. Switching Time
10nF
+5V
V+
V+
0V
V
IN
NC
V
NC
= 0V
MAX4529
V
IN
V
OUT
∆V
OUT
IN
COM
V
OUT
GND
V-
C = 1000pF
L
50Ω
10nF
∆V IS THE MEASURED VOLTAGE DUE TO CHARGE TRANSFER
OUT
ERROR Q WHEN THE CHANNEL TURNS OFF.
-5V
Q = ∆V x C
OUT
L
V- IS CONNECTED TO GND (0V) FOR SINGLE-SUPPLY OPERATION.
Figure 3. Charge Injection
10 ______________________________________________________________________________________
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
MAX4529
_________________________________Te s t Circ u it s /Tim in g Dia g ra m s (c o n t in u e d )
10nF
+5V
V+
V
V
OUT
OFF ISOLATION = 20log
ON LOSS = 20log
IN
NETWORK
ANALYZER
V
50Ω
50Ω
OUT
V
IN
0V OR V+
IN
V
IN
NC
MAX4529
MEAS
REF
V
OUT
COM
GND
V-
50Ω
50Ω
-5V
10nF
MEASUREMENTS ARE STANDARDIZED AGAINST SHORT AT IC TERMINALS.
OFF ISOLATION IS MEASURED BETWEEN COM_ AND "OFF" NC TERMINAL.
ON LOSS IS MEASURED BETWEEN COM_ AND "ON" NC TERMINAL.
SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED.
V- IS CONNECTED TO GND (0V) FOR SINGLE-SUPPLY OPERATION.
Figure 4. On Loss and Off Isolation
___________________Ch ip To p o g ra p h y
V+
10nF +5V
V+
NC
COM
0V OR V+
IN
NC
MAX4529
1MHz
0.054"
COM
CAPACITANCE
ANALYZER
(1.372mm)
GND
V-
N.C.
N.C.
10nF
-5V
GND
Figure 5. NC and COM Capacitance
V-
IN
0.038"
(0.965mm)
TRANSISTOR COUNT: 78
SUBSTRATE INTERNALLY CONNECTED TO V-
N.C. = NO CONNECTION
______________________________________________________________________________________ 11
Lo w -Vo lt a g e , Bid ire c t io n a l
RF/Vid e o S w it c h
________________________________________________________P a c k a g e In fo rm a t io n
MAX4529
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.
12 ____________________Ma x im In t e g ra t e d P ro d u c t s , 1 2 0 S a n Ga b rie l Drive , S u n n yva le , CA 9 4 0 8 6 4 0 8 -7 3 7 -7 6 0 0
© 1998 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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