ETC DG535DJ

DG535/536
Vishay Siliconix
16-Channel Wideband Video Multiplexers
FEATURES
BENEFITS
D
D
D
D
D
D
D
D High Video Quality
D Reduced Insertion Loss
D Reduced Input Buffer
Requirements
D Minimizes Power Consumption
D Simplifies Bus Interface
Crosstalk: –100 dB @ 5 MHz
300 MHz Bandwidth
Low Input and Output Capacitance
Low Power: 75 W
Low rDS(on): 50 On-Board Address Latches
Disable Output
APPLICATIONS
D
D
D
D
D
D
Video Switching/Routing
High Speed Data Routing
RF Signal Multiplexing
Precision Data Acquisition
Crosspoint Arrays
FLIR Systems
DESCRIPTION
The DG535/536 are 16-channel multiplexers designed for
routing one of 16 wideband analog or digital input signals to a
single output. They feature low input and output capacitance, low
on-resistance, and n-channel DMOS “T” switches, resulting in
wide bandwidth, low crosstalk and high “off” isolation. In the on
state, the switches pass signals in either direction, allowing them
to be used as multiplexers or as demultiplexers.
On-chip address latches and decode logic simplify
microprocessor interface. Chip Select and Enable inputs
simplify addressing in large matrices. Single-supply operation
and a low 75-W power consumption vastly reduces power
supply requirements.
Theses devices are built on a proprietary D/CMOS process
which creates low-capacitance DMOS FETs and high-speed,
low-power CMOS logic on the same substrate.
For more information please refer to Vishay Siliconix
Application Note AN501 (FaxBack document number 70608).
FUNCTIONAL BLOCK DIAGRAM AND PIN CONFIGURATION
DG536
S6
4
25
S12
S5
5
24
S13
S4
6
23
S14
S3
7
22
S15
S2
8
21
S16
S1
9
20
D
DIS
10
19
V+
CS
11
18
ST
CS
12
17
A3
16
A2
15
A1
Top View
Dual-In-Line
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
39
S6
8
38
GND
CS
9
37
S7
EN
10
36
GND
A0
11
35
S8
34
GND
33
S9
GND
Latches/
Decoders/
Drivers
A1
12
A2
13
A3
14
32
ST
15
31
S10
V+
16
30
GND
D
17
29
S11
GND
14
7
CS
GND
S12
A0
DIS
S14
GND
S13
13
1 44 43 42 41 40
18 19 20 21 22 23 24 25 26 27 28
Latches/Decoders/Drivers
EN
6 5 4 3 2
GND
S11
GND
S5
26
GND
S4
3
S3
S7
GND
S10
S2
27
GND
2
S15
GND
S8
S1
S9
GND
28
S16
GND
1
PLCC/Cerquad
GND
GND
DG535
Top View
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5-1
DG535/536
Vishay Siliconix
TRUTH TABLES AND ORDERING INFORMATION
ORDERING INFORMATION
Temperature Range
–40 to 85_C
_
Package
DG535DJ
44-Pin PLCC
DG536DN
28-Pin Sidebraze
–55 to 125
125_C
C
Part Number
28-Pin Plastic DIP
44-Pin Cerquad
DG535AP
DG535AP/883
DG536AM/883
TRUTH TABLE
EN
CS
CS
0
X
X
X
0
X
X
X
1
1
X
1
X
0
X
STa
A3
A2
A1
A0
Channel
Selected
Disableb
1
X
X
X
X
None
High Z
0
0
0
0
S1
0
0
0
1
S2
0
0
1
0
S3
0
0
1
1
S4
0
1
0
0
S5
0
1
0
1
S6
0
1
1
0
S7
0
1
1
1
S8
1
0
0
0
S9
1
0
0
1
S10
1
0
1
0
S11
1
0
1
1
S12
1
1
0
0
S13
1
1
0
1
S14
1
1
1
0
S15
1
1
1
1
S16
X
X
X
X
Maintains previous
switch condition
1
0
Low Z
High Z
or
Low Z
Logic “0” = VAL v 4.5 V
Logic “1” = VAH w 10.5 V
X = Don’t Care
Notes:
a. Strobe input (ST) is level triggered.
b. Low Z, High Z = impedance of Disable Output to GND. Disable output
sinks current when any channel is selected.
ABSOLUTE MAXIMUM RATINGS
V+ to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +18 V
Digital Inputs . . . . . . . . . . . . . . . . . . . . . . . . (GND – 0.3 V) to (V+ plus 2 V ) or
20 mA, whichever occurs first
28-Pin Sidebrazec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1200 mW
44-Pin PLCCd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450 mW
44-Pin Cerquade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 825 mW
VS, VD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (GND – 0.3 V) to V+ plus 2 V) or
20 mA, whichever occurs first
Current (any terminal) Continuous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA
Current (S or D) Pulsed 1 ms 10% duty cycle . . . . . . . . . . . . . . . . . . . . 40 mA
Storage Temperature
(A Suffix) . . . . . . . . . . . . . . . . . . . . –65 to 150_C
(D Suffix) . . . . . . . . . . . . . . . . . . . . –65 to 125_C
Power Dissipation (Package)a
28-Pin Plastic DIPb . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625 mW
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5-2
Notes:
a. All leads soldered or welded to PC board.
b. Derate 8.6 mW/_C above 75_C.
c. Derate 16 mW/_C above 75_C.
d. Derate 6 mW/_C above 75_C.
e. Derate 11 mW/_C above 75_C.
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
DG535/536
Vishay Siliconix
SPECIFICATIONSa
Test Conditions
Unless Otherwise Specified
Parameter
Symbol
V+ = 15 V, ST, CS = 10.5 V
CS = 4.5 V, VA = 4.5 or 10.5 Vf
Tempb
Typc
A Suffix
D Suffix
–55 to 125_C
–40 to 85_C
Minc
Maxc
Minc
Maxc
Unit
0
10
0
10
V
Analog Switch
Analog Signal Rangee
VANALOG
Drain-Source
On-Resistance
Room
Full
55
90
120
90
120
9
9
Resistance Match
rDS(on)
IS = –1 mA, VD = 3 V
EN = 10.5 V
Sequence Each Switch On
Source Off
Leakage Current
IS(off)
VS = 3 V, VD = 0 V, EN = 4.5 V
Room
Full
–10
–100
10
100
–10
–100
10
100
Drain On
Leakage Current
ID(on)
VS = VD = 3 V, EN = 10.5 V
Room
Full
–10
–1000
10
1000
–10
–100
–10
–100
RDISABLE
IDISABLE = 1 mA, EN = 10.5 V
Room
Full
Disable Output
rDS(on)
Full
Room
100
200
250
200
250
nA
Digital Control
Input Voltage High
VAIH
Full
Input Voltage Low
VAIL
Full
Address Input Current
IAI
Address Input
Capacitance
CA
VA = GND or V+
10.5
10.5
4.5
Room
Full
<0.01
Full
5
–1
–100
1
100
V
4.5
–1
–100
1
100
A
pF
Dynamic Characteristics
On State Input
Capacitancee
Off State Input
Capacitancee
Off State Output
Capacitancee
Multiplexer Switching Time
Break-Before-Make
Interval
CS(on)
CS(off)
CD(off)
VD = VS = 3 V
VS = 3 V
VD = 3 V
PLCC
Room
32
Cerquad
Room
35
45
DIP
Room
40
55
55
PLCC
Room
2
8
8
Cerquad
Room
5
DIP
Room
3
PLCC
Room
8
Cerquad
Room
12
DIP
Room
9
tTRANS
tOPEN
45
pF
Full
See Figure 4
Full
20
20
300
300
25
25
ns
EN, CS, CS, ST, tON
tON
See Figure 2 and 3
Full
300
300
EN, CS, CS, ST, tOFF
tOFF
See Figure 2
Full
150
150
Q
See Figure 5
Charge Injection
Single-Channel Crosstalk
Chip Disabled Crosstalk
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
XTALK(SC)
XTALK(CD)
RIN = 75 RL = 75 f = 5 MHz
See Figure 9
RIN = RL = 75 f = 5 MHz
EN = 4.5 V
See Figure 8
Room
–35
PLCC
Room
–100
Cerquad
Room
–93
DIP
Room
–60
PLCC
Room
–85
Cerquad
Room
–84
DIP
Room
–60
pC
dB
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5-3
DG535/536
Vishay Siliconix
SPECIFICATIONSa
Test Conditions
Unless Otherwise Specified
Parameter
V+ = 15 V, ST, CS = 10.5 V
CS = 4.5 V, VA = 4.5 or 10.5 Vf
Symbol
Tempb
Typc
PLCC
Room
–92
Cerquad
Room
–87
DIP
Room
–72
PLCC
Room
–74
Cerquad
Room
–74
DIP
Room
–60
A Suffix
D Suffix
–55 to 125_C
–40 to 85_C
Minc
Maxc
Minc
Maxc
Unit
Dynamic Characteristics (Cont’d)
Adjacent Input Crosstalk
RIN = 10 RL = 10 k
f = 5 MHz
See Figure 10
XTALK(AI)
All Hostile Crosstalke
RIN = 10 RL = 10 k
f = 5 MHz
See Figure 7
XTALK(AH)
BW
RL = 50 , See Figure 6
Room
500
Positive Supply Current
I+
Any One Channgel Selected with
All Logic Inputs at GND or V+
Room
Full
5
Supply Voltage Range
V+
Bandwidth
–60
dB
–60
MHz
Power Supplies
50
100
Full
10
16.5
10
Full
200
200
Full
100
100
Full
50
50
50
100
A
16.5
V
Minimum Input Timing Requirements
Strobe Pulse Width
tSW
A0, A1, A2, A3 CS, CS, EN
Data Valid to Strobe
tDW
A0, A1, A2, A3 CS, CS, EN
Data Valid after Strobe
tWD
See Figure 1
ns
Notes:
a. Refer to PROCESS OPTION FLOWCHART.
b. Room = 25_C, Full = as determined by the operating temperature suffix.
c. Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing.
d. The algebraic convention whereby the most negative value is a minimum and the most positive a maximum, is used in this data sheet.
e. Guaranteed by design, not subject to production test.
f.
VA = input voltage to perform proper function.
TYPICAL CHARACTERISTICS (25_C UNLESS NOTED)
rDS(on) vs. VD and Temperature
V+ = +15 V
GND = 0 V
360
320
280
125_C
240
200
160
120
25_C
80
–55_C
40
0
GND = 0 V
TA = 25_C
270
240
210
8V
180
12 V
150
15 V
120
90
60
30
0
0
2
4
6
VD – Drain Voltage (V)
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5-4
rDS(on) vs. VD and Power Supply Voltage
300
r DS(on)– Drain-Source On-Resistance ( )
r DS(on)– Drain-Source On-Resistance ( )
400
8
10
0
2
4
6
8
10
VD – Drain Voltage (V)
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
DG535/536
Vishay Siliconix
TYPICAL CHARACTERISTICS (25_C UNLESS NOTED)
Logic Input Switching Threshold
vs. Supply Voltage (V+)
Supply Current vs.
Supply Voltage and Temperature
14
10
9
GND = 0 V
TA = 25_C
8
GND = 0 V
12
7
10
6
8
I+ ( A)
V th (V)
125_C
5
4
3
25_C
6
4
–55_C
2
2
1
0
0
8
10
12
14
16
18
10
11
12
V+ – Positive Supply (V)
ID(on) vs. Temperature
14
15
16
17
18
Leakage Current vs. Temperature
1 A
V+ = +15 V
GND = 0 V
VD = VS = 3 V
100 nA
V+ = +15 V
GND = 0 V
100 nA
10 nA
I S, I D – Leakage
I D(on) – Leakage
13
V+ – Positive Supply (V)
1 nA
100 pA
10 pA
ID(off)
10 nA
IS(off)
1 nA
100 pA
10 pA
1 pA
1 pA
–55
–35
–15
5
25
45
65
85
105 125
–55
–35
–15
5
Temperature (_C)
25
45
65
85
105 125
Temperature (_C)
Adjacent Input Crosstalk vs. Frequency
–3 dB Bandwidth Insertion Loss vs. Frequency
0
–120
DG536
RIN = 10 –100
–4
Insertion Loss (dB)
X TALK(AI) (dB)
DG536
–80
DG536
RIN = 75 –60
DG535
RIN = 10 –40
–8
–3 dB Points
–12
Test Circuit
See Figure 6
RL = 50 –16
–20
DG535
Test Circuit
See Figure 10
–20
0
0.1
1
10
f – Frequency (MHz)
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
100
1
10
100
1000
f – Frequency (MHz)
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5-5
DG535/536
Vishay Siliconix
TYPICAL CHARACTERISTICS (25_C UNLESS NOTED)
Chip Disable Crosstalk vs. Frequency
All Hostile Crosstalk vs. Frequency
–160
–160
Test Circuit
See Figure 8
–140
DG536
RIN = 10 RL = 10 k
–120
–100
DG536
RL = 75 –80
X TALK(AH) (dB)
–120
X TALK(CD) (dB)
Test Circuit
See Figure 7
–140
DG536
RL = 50 DG535
RL = 75 –60
–100
DG536
RIN = 75 RL = 75 –80
–60
–40
–40
–20
–20
DG535
RIN = 10 RL = 10 k
0
0
0.1
1
10
100
0.1
1
f – Frequency (MHz)
tON, tOFF and Break-Before-Make vs. Temperature
Test Circuit
See Figures 2, 3, 4
Single Channel Crosstalk vs. Frequency
tON
–120
X TALK(SC) (dB)
120
Switching Time (ns)
Test Circuit
See Figure 9
RIN = 75 RL = 75 –140
100
tBBM
80
60
tOFF
40
100
–160
160
140
10
f – Frequency (MHz)
–100
DG536
–80
–60
DG535
–40
–20
20
0
0
–55 –35
–15
5
25
45
65
85
105 125
0.1
1
10
100
f – Frequency (MHz)
Temperature (_C)
INPUT TIMING REQUIREMENTS
15 V
ST
7.5 V
0V
tSW
tDW
tWD
15 V
10.5 V
10.5 V
4.5 V
4.5 V
CS, A0, A1, A2, A3
CS, EN
0V
FIGURE 1.
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5-6
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
DG535/536
Vishay Siliconix
TEST CIRCUITS
+15 V
+15 V
V+
ST
A0
A1
A2
A3
Logic
Input
Address
Logic Input
tr <20 ns
tf <20 ns
CS
15 V
50%
EN or CS
0V
+3 V
S16
S1 – S15
90%
EN or CS
CS
GND
VO
D
1 k
Signal
Output
35 pF
tON
tOFF
FIGURE 2. EN, CS, CS, Turn On/Off Time
+15 V
+15 V
Address
Logic Input
tr <20 ns
tf <20 ns
V+
EN, CS
A1, A2, A3
S2 – S15
Address
Input
15 V
50%
0V
+3 V
S1
15 V
0V
A0
ST
Logic
Input
VO
D
GND
CS
1 k
tON(ST)
VOUT
90%
35 pF
0V
FIGURE 3. Strobe ST Turn On Time
+15 V
+15 V
+3 V
Address
Logic Input
tr <20 ns
tf <20 ns
V+
EN
CS
ST
A0
A1
A2
A3
S1
S16
S2 thru S15
15 V
50%
0V
Switch
Output
90%
S1
Turning Off
D
GND
S16
Turning On
VO
tBBM
CS
1 k
35 pF
tTRANS
FIGURE 4. Transition Time and Break-Before-Make Interval
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
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5-7
DG535/536
Vishay Siliconix
TEST CIRCUITS
+15 V
+15 V
+15 V
V+
A0, A1, A2, A3
ST
EN
S16
+3 V
Logic
Input
D
VO
+15 V
CL
1000 pF
CS
GND
+15 V
CS
EN
CS
ST
V+
S2 thru S15
S1
CS
Signal
Generator
(75 )
VOUT
VOUT
GND
D
CS
VO
A0
to
A3
RL
50 W
VOUT is the measured voltage error due to charge injection.
The charge injection in Coulombs is Q = CL x VOUT
FIGURE 5. Charge Injection
FIGURE 6. Bandwidth
Channel 1 On
All Channels Off
S1
S1
RIN
S2
S2
S3
S3
S4
S4
S5
S5
S6
S6
S7
S7
S8
S8
VO
S9
S10
S10
S11
S12
S13
S13
S14
S14
S15
S15
S16
S16
X TALK(AH) + 20 log 10
VO
V
FIGURE 7. All Hostile Crosstalk
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5-8
S11
RL
S12
V
VO
S9
V
RL
X TALK(CD) + 20 log10
VO
V
FIGURE 8. Chip Disabled Crosstalk
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
DG535/536
Vishay Siliconix
TEST CIRCUITS
Channel 1 On
S1
S2
S3
RIN
S4
RIN
10 S5
S6
VSn–1
Sn–1
S7
VSn
S8
S9
Sn
VO
S10
VSn+1
S11
V
RL
Sn+1
RIN
10 S12
RL
10 k
S13
S14
S15
X TALK(AI) + 20 log10
S16
V Sn – 1
V Sn
or 20 log10
V Sn ) 1
V Sn
Notes:
1. Any individual channel between S2 and S16 can be selected
2. X TALK(SC) + 20 log10
VO
V
is scanned sequentially from S 2 to S 16
FIGURE 9. Single Channel Crosstalk
FIGURE 10.
Adjacent
Input Crosstalk
PIN DESCRIPTION
Symbol
S1 thru S16
D
DIS
CS, CS, EN
A0 thru A3
Description
Analog inputs/outputs
Multiplexer output/demultiplexer input
Open drain low impedance to analog ground when any channel is selected
Logic inputs to selected desired multiplexer(s) when using several multiplexers in a system
Binary address inputs to determine which channel is selected
ST
Strobe input that latches A0, A1, A2, A3, CS, CS, EN
V+
Positive supply voltage input
GND
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
Analog signal ground and most negative potential
All ground pins should be connected externally to ensure dynamic performance
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5-9
DG535/536
Vishay Siliconix
DETAILED DESCRIPTION
The DG535/536 are 16-channel single-ended multiplexers
with on-chip address logic and control latches.
Signal
IN
SW1
The multiplexer connects one of sixteen inputs (S1, S2 through
S16) to a common output (D) under the control of a 4-bit binary
address (A0 to A3). The specific input channel selected for
each address is given in the Truth Table.
All four address inputs have on-chip data latches which are
controlled by the Strobe (ST) input. These latches are
transparent when Strobe is high but they maintain the chosen
address when Strobe goes low. To facilitate easy
microprocessor control in large matrices a choice of three
independent logic inputs (EN, CS and CS) are provided on
chip. These inputs are gated together (see Figure 11) and only
when EN = CS = 1 and CS = 0 can an output switch be
selected. This necessary logic condition is then latched-in
when Strobe (ST) goes low.
Signal
OUT
SW3
SW2
Signal
GND
FIGURE 12.
“T” Switch
Arrangement
The two second level series switches further improve
crosstalk and help to minimize output capacitance.
The DIS output can be used to signal external circuitry. DIS is
a high impedance to GND when no channel is selected and a
low impedance to GND when any one channel is selected.
CS
Latch
CS
A1
Latch
EN
A2
Latch
Decode Logic
A0
Latch
A3
Latch
ST
The DG535/536 have extensive applications where any high
frequency video or digital signals are switched or routed.
Exceptional crosstalk and bandwidth performance is achieved
by using n-channel DMOS FETs for the “T” and series
switches.
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
Gate
Source
n+
FIGURE 11.CS, CS, EN, ST Control Logic
Break-before-make switching prevents momentary shorting
when changing from one input to another.
The devices feature a two-level switch arrangement whereby
two banks of eight switches (first level) are connected via two
series switches (second level) to a common DRAIN output.
In order to improve crosstalk all sixteen first level switches are
configured as “T” switches (see Figure 12).
With this method SW2 operates out of phase with SW1 and
SW3. In the on condition SW1 and SW3 are closed with SW2
open whereas in the off condition SW1 and SW3 are open and
SW2 closed. In the off condition the input to SW3 is effectively
the isolation leakage of SW1 working into the on-resistance of
SW2 (typically 200 ).
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5-10
Drain
n+
p
p–
Substrate
GND
FIGURE 13.
Cross-Section of a Single
DMOS Switch
It can clearly be seen from Figure 13 that there exists a PN
junction between the substrate and the drain/source terminals.
Should a signal which is negative with respect to the substrate
(GND pin) be connected to a source or drain terminal, then the
PN junction will become forward biased and current will flow
between the signal source and GND. This effective shorting of
the signal source to GND will not necessarily cause any
damage to the device, provided that the total current flowing
is less than the maximum rating, (i.e., 20 mA).
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
DG535/536
Vishay Siliconix
DETAILED DESCRIPTION
Since no PN junctions exist between the signal path and V+,
positive overvoltages are not a problem, unless the
breakdown voltage of the DMOS drain terminal (see Figure
13) (+18 V) is exceeded. Positive overvoltage conditions must
not exceed +18 V with respect to the GND pin. If this condition
is possible (e.g. transients in the signal), then a diode or Zener
clamp may be used to prevent breakdown.
The overvoltage conditions described may exist if the supplies
are collapsed while a signal is present on the inputs. If this
condition is unavoidable, then the necessary steps outlined
above should be taken to protect the device
being coupled back to the analog signal source and C2 blocks
the dc bias from the output signal. Both C1 and C2 should be
tantalum or ceramic disc type capacitors in order to operate
efficiently at high frequencies. Active bias circuits are
recommended if rapid switching time between channels is
required.
An alternative method is to offset the supply voltages (see
Figure 15).
Decoupling would have to be applied to the negative supply to
ensure that the substrate is well referenced to signal ground.
Again the capacitors should be of a type offering good high
frequency characteristics.
DC Biasing
To avoid negative overvoltage conditions and subsequent
distortion of ac analog signals, dc biasing may be necessary.
Biasing is not required, however, in applications where signals
are always positive with respect to the GND or substrate
connection, or in applications involving multiplexing of low
level (up to "200 mV) signals, where forward biasing of the
PN substrate-source/drain terminals would not occur.
Level shifting of the logic signals may be necessary using this
offset supply arrangement.
+12 V
Analog
Signal
IN
S
V+
DG536
Biasing can be accomplished in a number of ways, the
simplest of which is a resistive potential divider and a few dc
blocking capacitors as shown in Figure 14.
D
Analog
Signal
OUT
GND
Decoupling
Capacitors
+
–3 V
+15 V
Analog
Signal
IN
C1
FIGURE 15.
DG536 with
Offset Supply
R1
+
S
100 F/16 V
Tantalum
R2
V+
C2
+
DG536
GND
D
Analog
Signal
OUT
100 F/16 V
Tantalum
TTL to CMOS level shifting is easily obtained by using a
MC14504B.
Circuit Layout
FIGURE 14.
Simp
le Bias Circuit
R1 and R2 are chosen to suit the appropriate biasing
requirements. For video applications, approximately 3 V of
bias is required for optimal differential gain and phase
performance. Capacitor C1 blocks the dc bias voltage from
Document Number: 70070
S-02315—Rev. D, 05-Oct-00
Good circuit board layout and extensive shielding is essential
for optimizing the high frequency performance of the DG536.
Stray capacitances on the PC board and/or connecting leads
will considerably degrade the ac performance. Hence, signal
paths must be kept as short as practically possible, with
extensive ground planes separating signal tracks.
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