The AD724 is a low cost RGB to NTSC/PAL Encoder that converts red, green and blue color component signals into their corresponding luminance (baseband amplitude) and chrominance (subcarrier amplitude and phase) signals in accordance with either NTSC or PAL standards. These two outputs are also combined to provide composite video output. All three outputs can simultaneously drive 75 (ohm), reverse-terminated cables. All logical inputs are CMOS compatible. The chip operates from a single +5 V supply. No external delay lines or filters are required. The AD724 may be powered down when not in use.

The AD724 accepts either FSC or 4FSC clock. When a clock is not available, a low cost parallel-resonant crystal (3.58 MHz (NTSC) or 4.43 MHz (PAL)) and the AD724’s on-chip oscilla-tor generate the necessary subcarrier clock. The AD724 also accepts the subcarrier clock from an external video source.

The interface to graphics controllers is simple: an on-chip logic “XNOR” accepts the available vertical (VSYNC) and horizontal sync (HSYNC) signals and creates the composite sync (CSYNC) signal on-chip. If available, the AD724 will also accept a standard CSYNC signal by connecting VSYNC to +5 V and applying CSYNC to the HSYNC pin. The AD724 contains decoding logic to identify valid horizontal sync pulses for correct burst insertion.

Delays in the U and V chroma filters are matched by an on-chip sampled-data delay line in the Y signal path. To prevent aliasing, a prefilter at 5 MHz is included ahead of the delay line and a post-filter at 5 MHz is added after the delay line to suppress harmonics in the output. These low-pass filters are optimized for minimum pulse overshoot. The overall luma delay, relative to chroma, has been designed to be time aligned for direct input to a television’s baseband. The AD724 comes in a space-saving SOIC and is specified for the 0°C to +70°C commercial temperature range.

An evaluation board is available for this product and may be ordered using the following product number: AD724-EB.

Part#	# DAC	Resolution (Bits)	Input Data Resolution	Max Oversampling (MHz)	Standard Definition	Prog Scan	HDTV	Component RGB/YPbPr	CVBS/S-Video	Price* (1000-4999)
AD723	n/a	n/a	-	-	X	-	-	RGB only	X	$3.81
AD724	n/a	n/a	-	-	X	-	-	RGB only	X	$6.15
AD725	n/a	n/a	-	-	X	-	-	RGB only	X	$4.61
ADV7170	4	10	8	27	X	-	-	X	X	-
ADV7171	4	10	8	27	X	-	-	X	X	$5.46
ADV7172	6	10	8	27	X	-	-	X	X	-
ADV7173	6	10	8	27	X	-	-	X	X	$5.74
ADV7194	6	10	10	54	X	X	-	X	X	$21.22
ADV7324	6	14	-	-	X	X	X	-	X	-
ADV7340	6	12	10	297	X	X	X	X	X	-
ADV7341	6	12	10	297	X	X	X	X	X	$14.17
ADV7342	6	11	8	297	X	X	X	X	X	-
ADV7343	6	11	8	297	X	X	X	X	X	$7.74
ADV7344	6	14	10	297	X	X	X	X	X	-
ADV7390	3	10	8	297	X	X	X	X	X	-
ADV7391	3	10	8	297	X	X	X	X	X	$4.05
ADV7392	3	10	10	297	X	X	X	X	X	-
ADV7393	3	10	10	297	X	X	X	X	X	$4.40

* The pricing listed here is provided only for budgetary purposes as recommended list price in U.S. Dollars in the United States ex factor per unit for the stated volume. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
** Pricing is currently unavailable. Click on the product number to see the Product Page for additional information.

The model number is a specific version of a generic that can be purchased or sampled.

Status indicates the current lifecycle of the product. This can be one of 4 stages:

• Pre-Release: The model has not been released to general production, but samples may be available.
• Production: The model is currently being produced, and generally available for purchase and sampling.
• Last Time Buy: The model has been scheduled for obsolescence, but may still be purchased for a limited time.
• Obsolete: The specific part is obsolete and no longer available. Other models listed in the table may still be available (if they have a status that is not obsolete).

The package for this IC (i.e. DIP, SOIC, BGA). An Evaluation Board is a board engineered to show the performance of the model, the part is included on the board.

For detailed drawings and chemical composition please consult our  Package Site

Pin Count is the number of pins, balls, or pads on the device. Pin-out diagrams & pin function descriptions may be found in the datasheet.

This is the acceptable operating range of the device. The various ranges specified are as follows:

• Commercial: 0 to +70 degrees Celsius
• Military : -55 to +125 degrees Celsius
• Industrial: Temperature ranges may vary by model. Please consult the datasheet for more information.
• Automotive: -40 to +125 degrees Celsius

The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

This is the date Analog Devices, Inc. anticipates that the product will ship from the warehouse. Most orders ship within 48 hours of this date.Once an order has been placed, Analog Devices, Inc. will send an Order Acknowledgement email to confirm your delivery date. It is important to note the scheduled dock date on the order entry screen. We do take orders for items that are not in stock, so delivery may be scheduled at a future date. Also, please note the warehouse location for the product ordered. We have warehouses in the United States, Europe and Southeast Asia. Transit times from these sites may vary.

Due to environmental concerns, ADI offers many of our products in lead-free versions. For more information about lead-free parts, please consult our Pb (Lead) free information page.