Rainbow Electronics MAX7452 - Manual (Page 5)

MAX7450/MAX7451/MAX7452
Video-Signal Conditioners with AGC and
Back-Porch Clamp
_______________________________________________________________________________________ 5
PIN
MAX7450/
MAX7451
MAX7452
NAME FUNCTION
1 1 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.
2 2 IN Video Input. AC-couple video signal through a 0.1µF capacitor.
3 3 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.
5 5 AGCD
Automatic Gain-Control Disable Input. Disable AGC by driving AGCD to V CC . Enable AGC by
driving AGCD to GND.
6 6 OUT Video Output
7 7 GSET
Gain-Setting Input. Drive GSET high to set buffer gain to +6dB. Drive GSET low to set buffer
gain to 0dB.
8 8 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
1 µs
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
= 150 Ω to GND, C
L
= 0 to
20pF, GSET = 1, AGCD = 1. T
A
= +25 °C, unless otherwise noted.