TMC3503
PRODUCT SPECIFICATION
Pin Descriptions
Pin
Name
CLK
Pin Number
LQFP
26
PLCC
27
Value
TTL
Pin Function Description
Clock Input.
The clock input is TTL-compatible and all pixel
data is registered on the rising edge of CLK. It is recommended
that CLK be driven by a dedicated TTL buffer to avoid reflection
induced jitter, overshoot, and undershoot.
Red, Green, and Blue Pixel Inputs.
The R, G, and B digital
inputs are TTL-compatible and registered on the rising edge of
CLK.
Sync Pulse Input.
Bringing SYNC LOW, turns off a 40 IRE
(7.62 mA) current source which forms a sync pulse on any D/A
converter output connected to IO
S
. SYNC is registered on the
rising edge of CLK along with pixel data and has the same
pipeline latency as BLANK and pixel data. SYNC does not
override any other data and should be used only during the
blanking interval. If the system does not require sync pulses,
SYNC and IO
S
should be connected to GND.
Blanking Input.
When BLANK is LOW, pixel inputs are ignored
and the D/A converter outputs are driven to the blanking level.
BLANK is registered on the rising edge of CLK and has the
same two-pipe latency as SYNC and Data.
Force Full Scale Input.
When WHITE is HIGH, pixel inputs are
ignored and the D/A converter outputs are driven to their full-
scale output level. A BLANK input overwrites a WHITE input.
WHITE is register on the rising edge of CLK and has the same
two-pipe latency as SYNC and Data.
Power-down Control Input.
When HIGH, SLEEP places the D/
A converter in a low-power-dissipation mode. The D/A current
sources and the digital processing are disabled. The last data
loaded into the input and D/A registers is retained. This control is
asynchronous.
Red, Green, and Blue Data Outputs.
The current source
outputs of the D/A converters are capable of driving RS-343A/
SMPTE-170M compatible levels into doubly-terminated 75 Ohm
lines. Sync pulses may be added to any D/A output.
SYNC Current Output.
When this pin is connected to any of the
D/A converter outputs, a 40 IRE offset is added to the video
level. When the SYNC input is LOW, the current is turned off,
bring the sync tip voltage to 0.0V. If no sync pulse is required,
IO
S
should be grounded. When SYNC is HIGH, the current
flowing out of IO
S
is:
IO
S
= 3.64 (V
REF
/ R
REF
)
Voltage Reference
V
REF
35
41
+1.235 V
Voltage Reference Input/Output.
An internal voltage source of
+1.235 Volts is output on this pin. An external +1.235 Volt
reference may be applied here which overrides the internal
reference. Decoupling V
REF
to GND with a 0.1µF ceramic
capacitor is required.
Clock and Pixel I/O
R
7-0
G
7-0
B
7-0
Controls
SYNC
47-40
9-2
23-16
11
6-1, 44-43
14-7
25-18
16
TTL
TTL
BLANK
10
15
TTL
WHITE
—
26
TTL
SLEEP
—
28
TTL
Video Outputs
IO
R
IO
G
IO
B
IO
S
33
32
29
32
(connected
to IO
G
)
39
38
33
37
0.714 V
p-p
0.714 V
p-p
4
REV. 1.02 11/24/99
CADEKA [ CADEKA MICROCIRCUITS LLC. ]
