Rainbow Electronics MAX7452 User Manual

General Description

The MAX7450/MAX7451/MAX7452 complete front-end
video-signal conditioners are designed to improve the
quality of standard-definition video signals. The devices
restore the DC level of the video input, correct for
amplitude errors up to ±6dB, detect fault conditions,
and filter out-of-band noise. The MAX7450/MAX7451/
MAX7452 optimize the signal quality for further video
processing through a crosspoint switch or video
decoder (ADC). Each device integrates an input video
clamp, automatic gain control (AGC), loss-of-sync
(LOS) detector, and an out-of-band noise/lowpass filter.
These devices also incorporate a user-selectable
buffer gain (0 or +6dB) and an AGC-disable function.

The MAX7450 and MAX7451 operate from dual power
supplies of ±5V or ±3.3V respectively, and they restore
the video blanking level to GND. The MAX7452 operates
from a single +5V supply and features a user-adjustable
clamp level.

The devices are available in an 8-pin SO package with
an exposed pad and are specified for operation over
the extended (-40°C to +85°C) temperature range.

Applications

Signal Conditioner for Standard-Definition
Video Inputs

Security Video Systems

Video-Switching Systems

Features

♦ Back-Porch Clamp to GND (MAX7450/MAX7451)

♦ Adjustable Back-Porch Clamp (MAX7452)

♦ Automatic Gain Control (±6dB Range) Normalizes

Signals to Standard Video Level

♦ Input Fault Detection with LOS Output

♦ Inherent 50Hz/60Hz Input Rejection of 60dB

♦ Single-Supply Operation: MAX7452 (+5V)

♦ Out-of-Band Noise Filter

♦ Output Buffer Drives Standard 150Ω Video Load

with 0dB or +6dB Gain

♦ Dual-Supply Operation

MAX7450 (±5V)
MAX7451 (±3.3V)

♦ Tiny 8-Pin SO Package

MAX7450/MAX7451/MAX7452

Video-Signal Conditioners with AGC and

Back-Porch Clamp

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

19-3267; Rev 0; 4/04

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART

TEMP RANGE

PIN-

SUPPLY

VOLTAGE (V)

MAX7450ESA

±5

MAX7451ESA*

±3.3

MAX7452ESA

+5

MAX7450
MAX7451

NOISE
FILTER

V

CC

V

SS

75Ω

75Ω

LOS

SYNC SEPARATOR

AND AMPLITUDE

DETECTOR

AGCD

IN

OUT

VIDEO
INPUT

GND

±6dB

0 OR +6dB

GAIN SET (0dB OR +6dB)

Functional Diagram

*Future product—contact factory for availability.
**EP = Exposed pad.

PACKAGE

-40°C to +85°C8 SO-EP**

-40°C to +85°C8 SO-EP**

-40°C to +85°C8 SO-EP**

MAX7450/MAX7451/MAX7452

Video-Signal Conditioners with AGC and
Back-Porch Clamp

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V

SUPPLY

= ±5V ±5% (MAX7450), V

SUPPLY

= ±3.3V ±5% (MAX7451), V

SUPPLY

= +5V ±5% (MAX7452), RL=150Ω to GND, CL = 0 to

20pF, GSET = 1, AGCD = 1, T

A

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA = +25°C.)

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.

VCCto GND

MAX7450/MAX7452...........................................................+6V

MAX7451 ...........................................................................+4V

V

SS

to GND

MAX7450.............................................................................-6V

MAX7451.............................................................................-4V

OUT

MAX7450/MAX7451 ..........................................-2.5V to +3.5V

MAX7452................................................-0.3V to (V

CC

+ 0.3V)

GSET, AGCD, LOS.....................................-0.3V to (V

CC

+ 0.3V)

All Other Pins

MAX7450/MAX7451...................(-0.3V + V

SS

) to (VCC+ 0.3V)

MAX7452................................................-0.3V to (V

CC

+ 0.3V)

Maximum Current into Any Pin ............……………………±50mA

Continuous Power Dissipation (T

A

= +70°C)

8-Pin SO (derate 18.9mW/°C above +70°C)..............1509mW

Operating Temperature Range ...........................-40°C to +85°C

Storage Temperature Range .............................-65°C to +150°C

Junction Temperature......................................................+150°C

Lead temperature (soldering, 10s) ..................................+300°C

PARAMETER

CONDITIONS

UNITS

MAX7450/MAX7451, relative to GND

Clamp Accuracy

MAX7452, relative V

BPLVL

= 1.5V

mV

GSET = 0 1.0 3.0

Back-Porch Level Input Range V

BPLVL

MAX7452

GSET = 1 1.2 2.4

V

Clamp Response Time t

CLAMP

Blanking level at the output to 1% of final
value

70

Lines

GSET = 0, relative
to V

OUT

= 1V

P-P

AGC Accuracy

AGCD = 0,

GSET = 1, relative
to V

OUT

= 2V

P-P

%

AGC Input Range AGCD = 0, relative to VIN = 1V

P-P

dB

Gain Flatness G

F

f = 5MHz relative to 100kHz

dB

Noise-Filter Cutoff Fc 10

MHz

GSET = 0

1

Low-Frequency Gain f = 100kHz

GSET = 1

2

V/V

Group-Delay Deviation ∆t

G

3.58/4.43MHz relative to 100kHz 15 ns

Differential Gain dG

0.2 0.6 %

Differential Phase dθ

0.2 0.6

Degrees

SYMBOL

MIN TYP MAX

±50

±50

VIN = 0.5V

Five-step modulated staircase (VIN = 1V

Five-step modulated staircase (VIN = 1V

to 2V

P-P

P-P

)

P-P

)

P-P

-6.0 +6.0

-0.3 +0.3

0.95

1.85

±10

±10

1.05

2.05

MAX7450/MAX7451/MAX7452

Video-Signal Conditioners with AGC and

Back-Porch Clamp

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(V

SUPPLY

= ±5V ±5% (MAX7450), V

SUPPLY

= ±3.3V ±5% (MAX7451), V

SUPPLY

= +5V ±5% (MAX7452), RL=150Ω to GND, CL = 0 to

20pF, GSET = 1, AGCD = 1, T

A

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA = +25°C.)

PARAMETER

CONDITIONS

UNITS

GSET = 0,
V

OUT

= 1V

P-P

68

Signal-to-Noise Ratio SNR

Output signal
peak-to-peak to RMS

GSET = 1,
V

OUT

= 2V

P-P

65

dB

Line Time Distortion H

DIST

18µs, 100 IRE bar 0.2 %

Field Time Distortion V

DIST

130 lines, 18µs, 100IRE bar 0.5 %

Input Leakage Current I

IN

15µA

Output Dynamic Range VIN = 1V

P-P

, dG / dP < 3% / degrees 2 2.4

V

P-P

AGCD = 1 30

Power-Supply Rejection Ratio PSRR

V

CC

+ 100mV

P-P

,

f = 3.5MHz

AGCD = 0 with
maximum gain

20

dB

MAX7450 35

Supply Current

MAX7452 20

mA

Logic-High Input V

IH

0.7 x
V

Logic-Low Input V

IL

0.3 x
V

Logic-High Output V

OH

I

SOURCE

= 500µA

V

CC

-

0.5

V

Logic-Low Output V

OL

I

SINK

= 500µA 0.4 V

Input Current Logic-High I

IH

Logic input sink 10 µA

Input Current Logic-Low I

IL

Logic input source 10 µA

SYMBOL

noise (100Hz to 5MHz)

MIN TYP MAX

V

CC

V

CC