Analog Devices Inc. AD723ARU

Overview

AD723ARU from Analog Devices is a 28-lead TSSOP RGB-to-NTSC/PAL video encoder IC that converts analog R/G/B inputs into composite (CV) and S-video (Y/C) outputs for TV display. It operates from 2.7 V to 5.5 V, delivers <100 mW typical power in composite mode, supports smart load detection via TVDET pin, and integrates active termination for 75 Ω outputs - used in PC TV-out, digital cameras, and set-top boxes.

For engineers reviewing the AD723ARU datasheet, AD723ARU pinout, AD723ARU application, or AD723ARU equivalent, key selection considerations include NTSC/PAL dual-standard encoding capability, DC-coupled current-mode output drivers, integrated Y-trap for cross-color artifact reduction, triple RGB input termination switching, and 4FSC clock synchronization at 14.318 MHz (NTSC) or 17.734 MHz (PAL).

Technical Context

The AD723ARU implements a predominantly analog signal path with digital timing control synchronized to an external 4FSC clock. Its RGB-to-YUV matrix uses fixed coefficients (Y = 0.299R + 0.587G + 0.114B; U = 0.493(B−Y); V = 0.877(R−Y)) and includes dedicated 4-pole Bessel low-pass filters: 8 MHz pre-delay luma filter (NTSC), 10 MHz (PAL), and 6 MHz chroma output filter (NTSC).

Chrominance generation employs balanced quadrature modulators driven by internally derived FSC/4 sine/cosine clocks (3.579 MHz NTSC, 4.434 MHz PAL), with line-by-line V-phase inversion for PAL compliance. Luminance delay is implemented via an 8FSC-sampled delay line, ensuring precise Y/C time alignment within 19 ns.

Key Specifications

Pinout & Package

AD723ARU is housed in a 28-lead Thin Shrink Small Outline Package (TSSOP, RU-28), thermally rated at θ_JA = 67.7°C/W on SEMI 4-layer board, with exposed pad not electrically connected per datasheet.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RGB-to-analog-video encoding applications.

Compared with ADV7170KSTZ and THS8135PFP, the AD723ARU uniquely combines dual-standard NTSC/PAL encoding, integrated load detection, triple RGB termination switching, and YTRAP filtering in a single 28-pin TSSOP - reducing BOM count, layout complexity, and power management overhead for consumer electronics.

Availability

AD723ARU is available at Aetrix Electronics and suitable for TV-out interfaces in personal computers/laptops, digital cameras, and set-top boxes requiring stable component supply across extended product lifecycles.

Supply support for AD723ARU includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision instrumentation, communications, and industrial applications.

The AD723ARU belongs to Analog Devices' video encoder product line, designed specifically to simplify analog TV output integration in cost-sensitive, low-power consumer electronics with minimal external components.

FAQ

What video standards does the AD723ARU support?

The AD723ARU supports both NTSC and PAL encoding standards. STND pin logic level selects between them: HIGH for NTSC (14.318 MHz 4FSC clock, 4.7 MHz luma BW), LOW for PAL (17.734 MHz 4FSC clock, 6.1 MHz luma BW). The AD723ARU implements standard-compliant burst amplitude, phase, and timing for both formats without external configuration registers.

How does the AD723ARU implement smart load detection?

The AD723ARU performs periodic load checks on CV and Y outputs using internal DC level comparison against a reference. When CE is HIGH, it checks once per 64 fields (~1 Hz) in awake mode; in sleep mode, it applies a small test current to CV/CVSET or Y/YSET nodes. Detection result drives the open-drain TVDET pin - LOW indicates no load. This mechanism is integral to the AD723ARU's plug-and-play TV-out functionality.

What is the purpose of the YTRAP pin on the AD723ARU?

The YTRAP pin on the AD723ARU provides access to the luminance signal pre-filtering stage, allowing connection of an external series L-C resonant network tuned to 3.579 MHz (NTSC) or 4.434 MHz (PAL). This creates a notch filter that attenuates luminance energy at the chrominance subcarrier frequency, directly reducing cross-color artifacts in composite video receivers - a feature unique to the AD723ARU among single-chip encoders.

Can the AD723ARU operate from a 3.3 V supply?

Yes, the AD723ARU operates from 2.7 V to 5.5 V, making 3.3 V fully compliant. At 3.3 V, it delivers <100 mW typical power in composite mode and maintains all specified performance parameters including 4.7 MHz NTSC luma bandwidth and ±3° chroma phase error. The AD723ARU's current-mode outputs and internal biasing are designed for stable operation across this full voltage range.

What package type and thermal characteristics apply to the AD723ARU?

The AD723ARU is supplied in a 28-lead TSSOP (RU-28) package with θ_JA = 67.7°C/W measured on a SEMI standard 4-layer board. The package has no exposed thermal pad connection per datasheet. Maximum junction temperature is 150°C, and operating ambient range is –40°C to +85°C - validated for use in consumer electronics enclosures with moderate airflow.