IN 0
SIG GND
IN 1
SIG GND
IN 2
SIG GND
IN 3
V
CC
AO
A1
CS
OUT
LOGIC GND
V
EE
8
7
14
Pin 1
IN 0
SIG GND
IN 1
SIG GND
IN 2
SIG GND
IN 3
V
CC
AO
A1
CS
OUT
LOGIC GND
V
EE
8
7
14
Pin 1
FUNCTIONAL BLOCK DIAGRAM
GX214A Monolithic 4x1
Video Multiplexer
GENNUM CORPORATION P.O. Box 489, Stn A, Burlington, Ontario, Canada L7R 3Y3 tel. (905) 632-2996 fax: (905) 632-5946
Japan Branch: A-302 Miyamae Village, 2-10-42 Miyamae, Suginami-ku, Tokyo 168, Japan tel. (03) 3334-7700 fax: (03) 3247-8839
Document No. 520 - 5 - 1
CS
A1
A0
OUTPUT
0
0
0
IN 0
0
0
1
IN 1
0
1
0
IN 2
0
1
1
IN 3
1
X
X
HI - Z
X = DON'T CARE
TRUTH TABLE
ORDERING INFORMATION
PIN CONNECTION
14 PIN DIP
X
X
X
X
2 TO 4 DECODER
LOGIC
CHIP
SELECT
IN 0
IN 1
IN 2
IN 3
A0
A1
CS
OUTPUT
PIN CONNECTION
14 PIN SOIC
IN 0
SIG GND
IN 1
SIG GND
IN 2
SIG GND
IN 3
NC
V
CC
NC
AO
A1
CS
OUT
LOGIC GND
V
EE
8
9
16
Pin 1
PIN CONNECTION
16 PIN SOIC
Part Number
Package Type
Temperature Range
GX214 - ACDB 14 Pin DIP
0
to 70
C
GX214 - ACKC
16 Pin SOIC
0
to 70
C
GX214 - ACKB
14 Pin SOIC
0
to 70
C
FEATURES
low cost
differential gain at 3.58 MHz, 0.05% max.
differential phase at 3.58 MHz, 0.05 deg. max.
off-isolation better than 90 dB at 10 MHz
all hostile crosstalk at 3.58 MHz, 75 dB typ. (R
IN
= 75
)
make-before-break switching
CIRCUIT DESCRIPTION
The GX214A is a low cost 4x1 video multiplexer containing
four analog video switches and a 2 to 4 decoder. A Chip
Select input allows paralleled GX214As to be operated in
a switching matrix.
The GX214A represents a fully buffered, unilateral transmission
path when enabled. When disabled, the output is high
impedance.
The device operates from
7.5 V to
9.5 V supplies with
TTL and 5 V CMOS compatible input logic levels.
APPLICATIONS
CATV and CCTV systems
low cost video routing
DATA SHEET
520 - 5 - 1
2
Supply Voltage
V
S
7.5
8.0
9.5
V
DC
I+
Chip selected (CS=0)
-
14
20
mA
SUPPLY
Chip not selected (CS=1)
-
0.5
0.85
mA
I-
Chip selected (CS=0)
-
13
18
mA
Chip not selected (CS=1)
-
0.58
0.88
mA
Analog Output
V
OUT
Extremes before
+5.0
V
Voltage Swing
clipping occurs
-
-
-1.2
STATIC
Analog Input Bias
I
IN
-
25
-
A
Current
Output Offset Voltage
V
OS
75
resistor on each
+5
-30
-70
mV
input to ground
Turn-On Time
t
ON
Control input to appearance
-
250
400
ns
of signal at output.
Turn-Off Time
t
OFF
Control input to disappear-
500
750
-
ns
ance of signal at output.
LOGIC
Logic Input
V
IH
1
2.4
-
-
V
Thresholds
V
IL
0
-
-
0.6
V
Logic Input
I
BIAS
Chip Selected A0,A1 = 1
-
-
1
nA
Bias Current
Chip Selected A0,A1 = 0
-
-
2
A
Insertion Loss
I.L.
1V p-p sine or sq. wave
0.05
0.08
0.11
dB
at 100 kHz
Bandwidth (-3dB)
B.W.
65
85
-
MHz
Input Resistance
R
IN
Chip selected (CS = 0)
900
-
-
k
DYNAMIC
Input Capacitance
C
IN
Chip selected (CS = 0)
-
2.0
-
pF
Chip not selected (CS=1)
-
2.2
-
pF
Output Resistance
R
OUT
Chip selected (CS=0)
-
14
-
Output Capacitance
C
OUT
Chip not selected (CS=1)
-
12
-
pF
Differential Gain
dg
at 3.58 MHz
-
-
0.05
%
Differential Phase
dp
V
IN
= 40 IRE
-
-
0.05
deg.
Sweep on 3 inputs 1V p-p
All Hostile Crosstalk
X
TALK(AH)
4th input has 75
resistor
72
75
-
dB
to gnd. = 10 MHz
Chip Disabled Crosstalk
X
TALK(CD)
One xpt on output to ground
90
100
-
dB
= 10 MHz
Parameter
Value
Supply Voltage
10.0 V
Operating Temperature Range
0
C
T
A
70
C
Storage Temperature Range
-65
C
T
S
150
C
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Current
not including
I
L
ABSOLUTE MAXIMUM RATINGS
Parameter
Value
Lead Temperature
(Soldering, 10 Sec)
260
C
Analog Input Voltage
-4 V
V
IN
V
CC
+0.3 V
Logic Input Voltage
0 V
V
L
5.5 V
NOTE: A short from output to ground or either supply will destroy the device.
For R
EXT
use a 2.67 k
1%,
1
/
4
W resistor.
ELECTRICAL CHARACTERISTICS
V
S
=
8 V
DC
, 0
C < T
A
< 70
C, R
L
= 2.67 k
to V
EE
, C
L
= 30pF
I
L
= 3mA
520 - 5 - 1
3
INPUTS
VIDEO SWITCHES
V 0
V 1
V 2
V 3
75
75
75
75
0.1
1
2
6
5
4
3
7
9
10
11
12
13
14
8
1
2
6
5
4
3
7
9
10
11
12
13
14
8
V 4
V 5
V 6
V 7
75
75
75
75
0.1
0.1
0.1
-8V
-8V
+8V
+8V
A 0
A 1
A 2
IN 0
SG
IN 1
SG
IN 2
SG
IN 3
+V
A 0
A 1
CS
OUT
LG
-V
IN 0
SG
IN 1
SG
IN 2
SG
IN 3
+V
A 0
A 1
CS
OUT
LG
-V
ADDRESS
75
GAIN, OFFSET, FREQUENCY
RESPONSE ADJUSTMENTS
AMPLIFIER/BUFFER
V
OUT
2.67 K
An external load current of 2 to 8mA should be supplied
from each output bus to negative supply. For most applications
a load resistor of 2.67k
, 1% is recommended to minimize
offset drift with temperature. In order to improve differential
phase and tighten the insertion loss tolerance, an external
constant current active load may be substituted for the
load resistor. Note however, that since only one GX214A
output drives the output bus at any one time, only one
external load is needed for the bus.
A typical application is shown below. Two GX214A ICs are
paralleled to form an 8x1 crosspoint matrix. The three
address lines make use of the A0, A1 and CS inputs. If more
than two devices are used in parallel, a decoder is necessary
in order to generate the extra address inputs.
Depending on the application and the speed of the logic
family used, latches may be required for synchronization
where timing delays are critical. The active switching
circuitry of the GX214A ensures low crosstalk and high per-
formance over an input voltage range of -1.2 to +5.0 volts.
Fig. 1 8x1 Video Multiplexer Incorporating Two GX214A Devices
APPLICATION INFORMATION
The circuit layout of any wideband circuit is critical. Good
high frequency design practice, proper lead dress and
PCB component placement along with a well regulated and
decoupled power supply will assure optimum performance
of the crosspoint.
The GX214A is non-inverting. The inputs are buffered and
require 75
line terminating resistors when driven from 75
cable. The inputs may be driven directly from an amplifier
which has low output impedance.
The output of the GX214A must be buffered to drive 7
lines. The addition of an amplifier/buffer also allows adjustments
to be made to the gain, offset and frequency response of
the circuit.
Signal Ground (SG) pins 2, 4 and 6 must be joined together
and preferably form part of a ground plane. The Signal
Ground must also be connected to the
8V power supply
ground. The potential of the Logic Ground (LG) pin 9 can
deviate from the Signal Ground by
0.5V maximum. Alternatively,
the signal and logic grounds can be joined together at one
point only.
All resistors in ohms, all capacitors
in microfarads, unless otherwise stated
520 - 5 - 1
4
1
10
1
100
Fig. 2 Gain vs Frequency
Fig. 4 All - Hostile Crosstalk & Off-Isolation vs Frequency
1
10
100
GAIN (dB)
5
4
3
2
1
0
-1
-2
-3
-4
-5
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
-3.5
-4.0
-4.5
-5.0
PHASE (deg)
1
3
5 10
Fig. 3 Phase vs Frequency
FREQUENCY (MHz)
FREQUENCY (MHz)
*
*
1
10
dg(%) dp(
o
)
0.05
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
-0.03
-0.04
-0.05
FREQUENCY (MHz)
Fig. 5 Differential Gain & Phasevs Frequency
dg
dp
V
IN
=40
IRE
1
3
5 10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
GAIN (dB)
IN 1,2
XTALK (AH)
R
S
=75
OFF ISOLATION
R
L
=15
IN 0,3
1
10
100
FREQUENCY (MHz)
TYPICAL PERFORMANCE CURVES FOR GX214A
V
S
=
8V, C
L
= 30pF, I
L
= 3mA unless otherwise shown
14
2
10
75
8
11
+5V
0.1
4
0.1
1
TO
NETWORK
ANALYSER
8
5
CLC110
2.67k
FROM
NETWORK
ANALYSER
9
1
13
12
-8V
+8V
IN0
AG
A0
A1
CS
OUT
LG
V
CC
V
EE
-5V
* The power supply pins should be suitably decoupled with at least 0.1
F, high quality capacitors
All resistors in ohms, all capacitors in microfarads unless otherwise stated.
Fig. 6 Test Circuit
The TEST SET UP shown is for INPUT 0 tests. Similar circuitry is used for each input INPUT in order to test
FREQUENCY RESPONSE and PHASE DELAY. For OFF-ISOLATION, all switches are disabled (CHIP SELECT
= logic 1) and a second enabled GX214A is connected to the output bus. For ALL-HOSTILE CROSSTALK,
three OFF switches are driven from the generator and the fourth is terminated with a 75
resistor. For the
DIFFERENTIAL GAIN and PHASE tests, the output is AC coupled to the output amplifier and the input level
from the generator is modulated with a step signal varying between 0 volts DC and 0.714 volts DC.
520 - 5 - 1
5
Gennum Corporation assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement.
Copyright July 1990 Gennum Corporation. Revision Date: February 1993. All rights reserved. Printed in Canada.
DOCUMENT
IDENTIFICATION
PRODUCT PROPOSAL
This data has been compiled for market investigation purposes
only, and does not constitute an offer for sale.
ADVANCE INFORMATION NOTE
This product is in development phase and specifications are
subject to change without notice. Gennum reserves the right to
remove the product at any time. Listing the product does not
constitute an offer for sale.
PRELIMINARY DATA SHEET
The product is in a preproduction phase and specifications are
subject to change without notice.
DATA SHEET
The product is in production. Gennum reserves the right to make
changes at any time to improve reliability, function or design, in
order to provide the best product possible.
CAUTION
ELECTROSTATIC
SENSITIVE DEVICES
DO NOT OPEN PACKAGES OR HANDLE
EXCEPT AT A STATIC-FREE WORKSTATION
REVISION NOTES
.
Block diagram added,new test circuit, revised electrical
characteristics, new application circuit, all new response graphs.
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