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Timing circuits/timing diagrams (continued), Pin description – Rainbow Electronics MAX4885 User Manual

Page 8

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MAX4885

Complete VGA 1:2 or 2:1 Multiplexer

8

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Timing Circuits/Timing Diagrams (continued)

MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS.
OFF-ISOLATION IS MEASURED BETWEEN R0 AND R1 OR R2 ON EACH SWITCH.
ON-LOSS IS MEASURED BETWEEN R0 AND R1 OR R2 ON EACH SWITCH.
CROSSTALK IS MEASURED FROM ONE CHANNEL TO THE OTHER CHANNEL.
SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED.

+5V

V

OUT

V+

SEL

V

IN

MAX4885

OFF-ISOLATION = 20log

V

OUT

V

IN

ON-LOSS = 20log

V

OUT

V

IN

CROSSTALK = 20log

V

OUT

V

IN

NETWORK

ANALYZER

50

50

50

50

MEAS

REF

10nF

0V OR V+

50

GND

R0, G0, B0

R2, G2, B2

R1, G1, B1

Figure 4. On-Loss, Off-Isolation, and Crosstalk

Pin Description

PIN

NAME

FUNCTION

1

QP

Charge-Pump Enable, Active Low. Drive QP low for normal operation. Drive QP high to disable the
internal charge pump.

2

R0

RGB Analog I/O

3

G0

RGB Analog I/O

4

B0

RGB Analog I/O

5

H0

Horizontal Sync I/O

6

V0

Vertical Sync I/O

7

DDCA0

DDC I/O

8

DDCB0

DDC I/O

9

EN

Enable Input, Active Low. Drive EN low for normal operation. Drive EN high to disable the device. All
I/Os are high-impedance and charge pump is off when the device is disabled.

10

V

CL

DDC Clamp Voltage. Open-drain DDCA_ and DDCB_ outputs are clamped to one diode-drop below
V

CL

. +2.7V < V

CL

< V+. Connect V

CL

to +3.3V for voltage clamping, or connect to V+ to disable

clamping. Bypass V

CL

to GND with a 0.1µF or larger ceramic capacitor.

11, 21, 30

V+

Supply Voltage. V+ = +5.0V ± 10%. Bypass each to GND with a 0.1µF or larger ceramic capacitor.

12, 20, 29

GND

Ground

13

DDCA2

DDC I/O

14

DDCB2

DDC I/O

15

R2

RGB Analog I/O

16

G2

RGB Analog I/O

17

B2

RGB Analog I/O