MAX9512ATE+ Maxim Integrated Products, MAX9512ATE+ Datasheet - Page 11

• Manufacturer Part Number: MAX9512ATE+
• Description: IC AMP VIDEO FILTER 16-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX9512ATE+

• Applications: Filter
• Number Of Circuits: 1
• Current - Supply: 13mA
• Voltage - Supply, Single/dual (±): 2.7 V ~ 3.6 V
• Mounting Type: Surface Mount
• Package / Case: 16-TQFN Exposed Pad
• Number Of Channels: 2
• Supply Current: 13 mA
• Minimum Operating Temperature: - 40 C
• Maximum Operating Temperature: + 125 C
• Maximum Power Dissipation: 1250 mW
• Mounting Style: SMD/SMT
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 2.7 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The active video detect circuit slices the YIN signal at
4.7% of the power supply (155mV for a 3.3V supply). If
the transitions occur at a rate of 14.3kHz or higher,
then a video signal is present. When the MAX9512
detects a video signal with sync at the YIN input, the
control logic enters the active-detect mode and
enables the load sense circuitry (Figure 3). The supply
current is typically 17µA.
If an output load is not connected to any amplifier, the
MAX9512 remains in active-detect mode. Eight times per
second, each load-sense circuit checks for a load by
connecting an internal 15kΩ pullup resistor to the output
for 1ms. If the output is pulled up, then no load is pre-
sent. If the output stays low, a load is connected.
If a load is connected to an output, the corresponding
filter and amplifier turn on and remain on until the out-
put load is disconnected. In full-operation mode,
SmartSleep intelligently reduces the supply current
Figure 3. Active-Detect Mode with No Output Loads
VIDEO ENCODER
CURRENT
CURRENT
DAC
DAC
50mV
TO
0
+3.3V
______________________________________________________________________________________
VIDEO SIGNAL
Video Filter Amplifier with SmartSleep
PRESENT
SMARTSLEEP
SHDN
CIN
YIN
Full-Operation Mode
Active-Detect Mode
BUFFER
BUFFER
OFF
OFF
MAX9512
ACTIVE VIDEO
CONTROL
DETECT
LOGIC
LPF
LPF
OFF
OFF
17μA
OFF
+3.3V
V
GND
based on the input signal presence and output loading.
Figures 4 and 5 show which portions of the MAX9512
turn on and which remain off with different load configu-
rations. In Figure 4, both filters and the Y/C mixer turn
on to generate the composite video signal for the ampli-
fier connected to CVBSOUT1. In Figure 5, only the luma
filter turns on, and the Y/C mixer stays off.
When an amplifier is on, it continually checks if the load
has been disconnected by detecting if the amplifier
output is sourcing current during a horizontal line time.
If no sourcing current is detected within one horizontal
line time (approximately 64µs), the load has been dis-
connected and the amplifier returns to active-detect
mode. If, at any time, the input video signal is removed,
the MAX9512 returns to standby mode.
If the SmartSleep feature is not activated and the part is
not in shutdown, then the filters and amplifiers com-
pletely turn on, regardless of whether there is a video
signal at the CVBSIN input and whether there are loads
connected at the outputs.
DD
and Y/C Mixer Circuit
6dB
6dB
6dB
6dB
OFF
OFF
OFF
OFF
LOAD SENSE
LOAD SENSE
LOAD SENSE
LOAD SENSE
YOUT
COUT
CVBSOUT1
CVBSOUT2
75Ω
75Ω
75Ω
75Ω
CHROMA
CVBS1
CVBS2
LUMA
NO
LOADS
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