19-0137; Rev 1; 3/94
Improved Low-Power,
CMOS Analog Switches with Latches
_______________General Description
Maxim’s redesigned DG421/DG423/DG425 monolithic
analog switches now feature guaranteed on-resistance
matching (3Ω max) between switches and on-resistance
flatness over the signal range (4Ω max). These low on-
resistance switches (20Ω typ) conduct equally well in both
directions. They guarantee a low charge injection of 15pC
maximum and an ESD tolerance of 2000V minimum per
Method 3015.7. Off leakage current over temperature has
also been reduced (less than 5nA at +85°C).
The DG421/DG423/DG425 are precision, dual CMOS
switches with latchable logic inputs that simplify inter-
facing with microprocessors (µPs). The single-pole/single-
throw DG421 and double-pole/single-throw DG425 are
normally open dual switches. The dual, single-
pole/double-throw DG423 has two normally open and
two normally closed switches. Fast switching times
(175ns for t
ON
and 145ns for t
OFF
) and low power
consumption (35µW max) make these parts ideal for
battery-powered applications requiring µP-compatible
switches. Operation is from a single +10V to +30V supply,
or bipolar ±4.5V to ±20V supplies. Fabricated with the
same 44V silicon-gate process, these switches have
rail-to-rail signal handling capabilities.
______________________New Features
o
Plug-In Upgrades for Industry-Standard
DG421/DG423/DG425
o
Improved r
(DS)ON
Match Between Channels (3Ω max)
o
Guaranteed r
FLAT(ON)
Over Signal Range (4Ω max)
o
Improved Charge Injection (15pC max)
o
Improved Off Leakage Current Over Temperature
(<5nA at +85°C)
o
Withstands Electrostatic Discharge (2000V min)
per Method 3015.7
DG421/DG423/DG425
__________________Existing Features
o
Low r
DS(ON)
(35Ω max)
o
Single-Supply Operation +10V to +30V
Bipolar-Supply Operation ±4.5V to ±20V
o
Low Power Consumption (35µW max)
o
Rail-to-Rail Signal Handling Capability
o
TTL/CMOS-Logic Compatible
______________Ordering Information
PART
DG421CJ
DG421CY
DG421C/D
DG421DJ
DG421DY
DG421DK
DG421AK
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
PIN-PACKAGE
16 Plastic DIP
16 SO
Dice*
16 Plastic DIP
16 SO
16 CERDIP
16 CERDIP**
_______________________Applications
Sample-and-Hold Circuits
Fax Machines
Battery-Operated Systems
Guidance and Control Systems
Audio Signal Routing
Modems
Test Equipment
PBX, PABX
Military Radios
Communication Systems
Ordering Information continued at end of data sheet.
* Contact factory for dice specifications.
**Contact factory for availability and processing to MIL-STD-883B.
__Functional Diagrams/Truth Tables
S1
WR
IN1
D
IN2
D
RS
S2
CK
R
Q
D2
CK
R
Q
DG421 TRUTH TABLE
WR RS IN
SWITCH
D1
_________________Pin Configurations
TOP VIEW
D1 1
WR 2
N.C. 3
N.C. 4
N.C. 5
N.C. 6
RS 7
D2 8
16 S1
15 IN1
14 V-
DG421
13 GND
12 V
L
11 V+
10 IN2
9
S2
DG421
0
1
0
1
Off
On
LOGIC "O"
≤
0.8V
LOGIC "1"
≥
2.4V
SWITCHES SHOWN FOR
LOGIC "1" INPUT
TWO SPST SWITCHES
PER PACKAGE
Functional Diagrams/Truth Tables continued at end of data sheet.
DIP
N.C. = No Internal Connection
Pin Configurations continued at end of data sheet.
1
________________________________________________________________
Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
Improved Low-Power,
CMOS Analog Switches with Latches
DG421/DG423/DG425
ABSOLUTE MAXIMUM RATINGS
Voltage Referenced to V-
V+ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44V
GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25V
V
L
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (GND - 0.3V) to (V+ + 0.3V)
Digital Inputs, V
S
, V
D
(Note 1) . . . . . . . . . . . . . . (V- - 2V) to (V+ + 2V)
Current (any terminal, except S or D) .................................30mA
Continuous Current, S or D .................................................20mA
Peak Current, S or D (pulsed at 1ms, 10% duty cycle max)...100mA
Continuous Power Dissipation (T
A
= +70°C)
16-Pin Plastic DIP (derate 10.53mW/°C above +70°C) . . .842mW
20-Pin PLCC (derate 10.00mW/°C above +70°C) . . . . . 800mW
16-Pin CERDIP (derate 10.00mW/°C above +70°C) . . . 800mW
Operating Temperature Ranges
DG42_C_ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to +70°C
DG42_D_ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C
DG42_A_ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55°C to +125°C
Storage Temperature Ranges
DG42_C_/DG42_D_ . . . . . . . . . . . . . . . . . . . . . . . . . . . -65°C to +125°C
DG42_A_ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -65°C to +150°C
Lead Temperature (soldering, 10sec). . . . . . . . . . . . . . . . . . . . +300°C
Note 1:
Signals on S, D, or IN exceeding V+ or V- are clamped by internal diodes. Limit forward current to maximum current ratings.
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
(V+ = 15V, V- = -15V, V
L
= +5V, GND = 0V, V
INH
= +2.4V, V
INL
= +0.8V, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
SWITCH
Analog Signal Range
Drain-Source
On-Resistance
V
ANALOG
(Note 3)
V+ = 13.5V,
V- = -13.5V,
I
S
= -10mA,
V
D
= ±10V
V+ = 16.5V,
V- = -16.5V,
I
S
= -10mA,
V
D
= ±10V
V+ = 15V,
V- = -15V,
I
S
= -10mA,
V
D
= ±5V
V+ = 16.5V,
V- = -16.5V,
V
D
= ±15.5V,
V
S
=
m
15.5V
V+ = 16.5V,
V- = -16.5V,
V
D
= ±15.5V,
V
S
=
m
15.5V
V+ = 16.5V,
V- = -16.5V,
V
D
= ±15.5V,
V
S
= ±15.5V
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
-0.50 -0.01
-5
-0.50 -0.01
-5
-1.0
-10
-0.04
-15
20
15
45
45
3
4
4
5
0.50
5
0.50
5
1.0
10
-0.25 -0.01
-10
-0.25 -0.01
-10
-0.40 -0.04
-20
-15
20
15
35
Ω
45
3
Ω
4
4
Ω
5
0.25
nA
10
0.25
nA
10
0.40
nA
20
V
SYMBOL
CONDITIONS
DG42_C, DG42_D
MIN TYP MAX
(Note 2)
MIN
DG42_A
TYP MAX
(Note 2)
UNITS
r
DS(ON)
On-Resistance Match
Between Channels
(Note 4)
∆r
DS(ON)
On-Resistance
Flatness (Note 4)
r
FLAT(ON)
Source-Off
Leakage Current
(Note 5)
Drain-Off
Leakage Current
(Note 5)
Drain-On
Leakage Current
(Note 5)
2
I
S(OFF)
I
D(OFF)
I
D(ON)
_______________________________________________________________________________________
Improved Low-Power,
CMOS Analog Switches with Latches
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 15V, V- = -15V, V
L
= +5V, GND = 0V, V
INH
= +2.4V, V
INL
= +0.8V, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
INPUT
Input Current with Input Voltage High
Input Current with Input Voltage Low
SUPPLY
Power Supply Range
Positive Supply Current
SYMBOL
CONDITIONS
MIN
TYP MAX
(Note 2)
0.005
0.005
0.50
0.50
±20
0.01
1.0
µA
-5.0
-1.0
-5.0
-1.0
-5.0
-1.0
-5.0
150
-0.01
-0.01
-0.01
5.0
1.0
µA
5.0
1.0
µA
5.0
1.0
µA
5.0
250
300
200
UNITS
DG421/DG423/DG425
I
INH
I
INL
V+, V-
I+
IN = 2.4V, all others = 0.8V
IN = 0.8V, all others = 2.4V
(Note 3)
All channels on or off,
V+ = 16.5V, V- = -16.5V,
V
IN
= 0V or 5V
All channels on or off,
V+ = 16.5V, V- = -16.5V,
V
IN
= 0V or 5V
All channels on or off,
V+ = 16.5V, V- = -16.5V,
V
IN
= 0V or 5V
All channels on or off,
V+ = 16.5V, V- = -16.5V,
V
IN
= 0V or 5V
-0.50
-0.50
±4.5
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= -55°C to +125°C
T
A
= +25°C
T
A
= -55°C to +125°C
T
A
= +25°C
T
A
= -55°C to +125°C
T
A
= +25°C
T
A
= +25°C
T
A
= +25°C
T
A
= +25°C
T
A
= +25°C
T
A
= +25°C
T
A
= +25°C
T
A
= +25°C
200
200
100
100
60
100
5
-1.0
µA
µA
V
Negative Supply Current
I-
Logic Supply Current
I
L
Ground Current
DYNAMIC
Turn-On Time
Turn-Off Time
I
GND
t
ON
t
OFF
t
WW
Figure 2
Figure 2
V
S
= ±10V,
R
L
= 300Ω,
C
L
= 35pF,
Figure 3
DG423, Figure 4
C
L
= 10nF, V
G
= 0V,
R
G
= 0Ω, Figure 5
R
L
= 100Ω, C
L
= 5pF,
f = 1MHz, Figure 6
R
L
= 50Ω, C
L
= 5pF,
f = 1MHz, Figure 7
ns
ns
Latch Timing
t
DW
t
WD
ns
Break-Before-Make Interval (Note 3)
Charge Injection (Note 3)
Off-Isolation Rejection Ratio
(Note 6)
Crosstalk (Note 7)
Drain-Off Capacitance
Source-Off Capacitance
Drain-On Capacitance
Source-On Capacitance
t
D
Q
OIRR
25
10
72
90
12
12
39
39
15
ns
pC
dB
dB
pF
pF
pF
pF
C
D(OFF)
C
S(OFF)
C
D(ON)
C
S(ON)
f = 1MHz, Figure 8
f = 1MHz, Figure 8
f = 1MHz, Figure 9
f = 1MHz, Figure 9
Note 2:
Typical values are
for design aid only,
are not guaranteed, and are not subject to production testing. The algebraic convention,
where the most negative value is a minimum and the most positive value a maximum, is used in this data sheet.
Note 3:
Guaranteed by design.
Note 4:
On-resistance match between channels and flatness are guaranteed only with bipolar-supply operation. Flatness is defined as the dif-
ference between the maximum and minimum value of on-resistance as measured at the extremes of the specified analog signal range.
Note 5:
Leakage parameters I
S(OFF)
, I
D(OFF)
, and I
D(ON)
are 100% tested at the maximum rated hot temperature and guaranteed by
correlation at +25°C.
Note 6:
Off-Isolation Rejection Ratio = 20log (V
D
/V
S
), V
D
= output, V
S
= input to off switch.
Note 7:
Between any two switches.
_______________________________________________________________________________________
3
Improved Low-Power,
CMOS Analog Switches with Latches
DG421/DG423/DG425
__________________________________________Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
ON-RESISTANCE vs. V
D
(DUAL-SUPPLIES)
MAX401-1
ON-RESISTANCE vs. V
D
AND
TEMPERATURE (DUAL SUPPLIES)
MAX401-2
ON-RESISTANCE vs. V
D
(SINGLE SUPPLY)
V- = 0V
120
100
r
DS (ON)
(Ω)
80
60
V+ = 10V
40
MAX401-3
55
50
45
40
r
DS (ON)
(Ω)
35
30
25
20
15
10
5
A:
B:
C:
D:
V+ = 5V, V- = -5V
V+ = 10V, V- = -10V
V+ = 15V, V- = -15V
V+ = 20V, V- = -20V
35
30
25
r
DS (ON)
(Ω)
20
15
T
A
= -55°C
T
A
= +125°C
T
A
= +85°C
T
A
= +25°C
140
A
V+ = 5V
B
C
D
10
V+ = 15V, V- = -15V
5
-20
-10
0
V
D
(V)
10
20
-20
-10
0
V
D
(V)
10
20
V+ = 15V
0
5
10
V
D
(V)
15
V+ = 20V
20
20
ON-RESISTANCE vs. V
D
AND
TEMPERATURE (SINGLE SUPPLY)
MAX401-4
OFF LEAKAGE CURRENTS vs.
TEMPERATURE
V+ = 16.5V
V- = -16.5V
V
D
= ±15V
V
S
= ±15V
MAX401-5
ON LEAKAGE CURRENTS vs.
TEMPERATURE
V+ = 16.5V
V- = -16.5V
V
D
= ±15V
V
S
= ±15V
MAX401-6
70
60
T
A
= +125°C
100
10
OFF LEAKAGE (nA)
1
0.1
0.01
100
10
ON LEAKAGE (nA)
1
0.1
0.01
50
r
DS (ON)
(Ω)
40
30
20
V+ = 12V, V- = 0V
10
0
5
10
V
D
(V)
T
A
= +85°C
T
A
= +25°C
0.001
0.0001
15
20
-75
25
TEMPERATURE (°C)
125
0.001
0.0001
-75
25
TEMPERATURE (°C)
125
CHARGE INJECTION vs.
ANALOG VOLTAGE
MAX401-7
SUPPLY CURRENT vs.
TEMPERATURE
MAX401-8
60
40
20
Q (pC)
0
-20
-40
V+ = 15V, V- = -15V
-60
-20
-10
0
V
D
(V)
10
100
10
1
0.1
0.01
0.001
0.0001
I+, I-, I
L
(µA)
I+ at V+ = 16.5V
I- at V- = -16.5V
I
L
at V
L
= 5V
20
-75
25
TEMPERATURE (°C)
125
4
_______________________________________________________________________________________
Improved Low-Power,
CMOS Analog Switches with Latches
___________________Pin Descriptions
DG421
PIN
1, 8
2
3, 4, 5, 6
7
9, 16
10, 15
11
12
13
14
NAME
D1, D2
–––
—
–
WR
N.C.
––
—
––
RS
S1, S2
IN1, IN2
V+
V
L
GND
V-
FUNCTION
Drain Terminals
Write Select
No Internal Connection
Reset Select
Source Terminals
Input Control
Positive Supply
Logic Supply
Ground
Negative Supply
DG423/DG425
DIP
1, 8, 3, 6
2
PLCC
2, 10, 4, 8
3
NAME
D1-D4
–––
—
–
WR
S1-S4
––
—
––
RS
IN1, IN2
V+
V
L
N.C.
V-
GND
FUNCTION
Drain Terminals
Write Select
Source Terminals
Resets Select
Input Control
Positive Supply
Logic Supply
No Internal Connection
Negative Supply
Ground
V+
__________Applications Information
Operation with Supply Voltages
Other Than ±15V
The DG421/DG423/DG425 switches operate with ±4.5V
to ±20V bipolar supplies or with a +10V to +30V single
supply. In either case, analog signals ranging from V+
to V- can be switched. The
Typical Operating
Characteristics
graphs illustrate typical analog-signal
and supply-voltage on-resistance variations. The usual
on-resistance temperature coefficient is 0.5%/°C (typ).
DG421/DG423/DG425
Logic Inputs
These devices operate with a single positive supply or
with bipolar supplies. They maintain TTL compatibility
with supplies anywhere in the ±4.5V to ±20V range as
long as V
L
= +5V. If V
L
is connected to V+ or another
supply at voltages other than +5V, the devices will
operate at CMOS-logic-level inputs.
Overvoltage Protection
Proper power-supply sequencing is recommended for
all CMOS devices. Do not exceed the absolute maxi-
mum ratings because stresses beyond the listed rat-
ings may cause permanent damage to the devices.
Always sequence V+ on first, followed by V
L
, V-, and
logic inputs. If power-supply sequencing is not possi-
ble, add two small, external signal diodes in series with
supply pins for overvoltage protection (Figure 1).
Adding diodes reduces the analog signal range to 1V
below V+ and 1V above V-, without affecting low switch
resistance and low leakage characteristics. Device
operation is unchanged, and the difference between V+
and V- should not exceed +44V.
16, 9, 4, 5 20, 12, 5, 7
7
15, 10
11
12
—
14
13
9
19, 13
14
15
1, 6, 11, 16
18
17
S
D
V
g
V-
Figure 1. Overvoltage Protection Using External Blocking Diodes
_______________________________________________________________________________________
5
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