Owner manual

MAX7450/MAX7451/MAX7452
Video-Signal Conditioners with AGC and
Back-Porch Clamp
_______________________________________________________________________________________ 5
PIN
MAX7450/
MAX7451
MAX7452
NAME
FUNCTION
11
V
CC
Positive Power Supply. Connect +5V to V
CC
for the MAX7450/MAX7452. Connect +3.3V to V
CC
for the MAX7451. Bypass to GND with 1µF and 0.1µF capacitors as close to the pin as possible.
22IN Video Input. AC-couple video signal through a 0.1µF capacitor.
33
GND
Ground
4—
V
SS
Negative Power Supply. Connect -5V to V
SS
for the MAX7450. Connect -3.3V to V
SS
for the
MAX7451. Bypass to GND with 1µF and 0.1µF capacitors as close to the pin as possible.
—4
BPLVL
Back-Porch Level Input. When gain = 2V/V (GSET = 1), output back-porch level is equal to
BPLVL input. When gain = 1V/V (GSET = 0), output back-porch level is equal to V
BPLVL
/1.5.
55
AGCD
Automatic Gain-Control Disable Input. Disable AGC by driving AGCD to V
CC
. Enable AGC by
driving AGCD to GND.
66
OUT
Video Output
77
GSET
Gain-Setting Input. Drive GSET high to set buffer gain to +6dB. Drive GSET low to set buffer
gain to 0dB.
88
LOS
Loss-of-Sync Logic Output. LOS is high when video sync is lost for more than 15 horizontal
lines. LOS goes low when video sync is present.
——EP Exposed Pad. Connect to V
SS
(MAX7450/MAX7451). Connect to GND (MAX7452).
Pin Description
OUTPUT BACK-PORCH LEVEL (MAX7450)
MAX7450 toc08
1µs
IN
AC-COUPLED
200mV/div
OUT
200mV/div
BACK-PORCH = 0V
AGC RESPONSE ENVELOPE (V
IN
= 0.5V
P-P
)
MAX7450 toc09
400ms/div
500mV/div
AGCD = 0
V
OUT
= 2V
P-P
AGC RESPONSE ENVELOPE (V
IN
= 2V
P-P
)
MAX7450 toc10
400ms/div
500mV/div
AGCD = 0
V
OUT
= 2V
P-P
Typical Operating Characteristics (continued)
V
SUPPLY
= ±5V ±5% (MAX7450), V
SUPPLY
= ±3.3V ±5% (MAX7451), V
SUPPLY
= +5V ±5% (MAX7452), R
L
= 150Ω to GND, C
L
= 0 to
20pF, GSET = 1, AGCD = 1. T
A
= +25°C, unless otherwise noted.