AS1109 LED Driver IC

Description

The AS1109 is designed to drive up to 8 LEDs through a fast serial interface and features 8 output constant current drivers and an on-chip diagnostic read-back function.

The high clock-frequency (up to 50MHz), adjustable output current, and flexible serial interface makes the device perfectly suited for high-volume transmission applications. Output current is adjustable (up to 100mA/channel) using an external resistor (REXT).

The serial interface with Schmitt trigger inputs includes an integrated shift register. Additionally, an internal data register stores the currently displayed data.

The device features integrated diagnostics for overtemperature, open-LED, and shorted-LED conditions. Integrated registers store global fault status information during load as well as the detailed temperature/open-LED/shorted-LED diagnostics results. The AS1109 also features a low-current diagnostic mode to minimize display flicker during fault testing.

With an operating temperature range from -40°C to +125°C, the AS1109 is also ideal for industrial applications.

The AS1109 is available in a 16-pin SOIC-150, a 16-pin QFN (4x4mm) and the 16-pin SSOP-150 package.

Key Features

• 8 Constant-Current Output Channels
• Excellent Output Current Accuracy
  • Between Channels: ±2%
  • Between AS1109 Devices: ±2%
• Output Current Per Channel: 0.5 to 100mA
• Controlled In-Rush Current
• Over-Temperature, Open-LED, Shorted-LED, Diagnostics Functions
• Low-Current Test Mode
• Global Fault Monitoring
• Low Shutdown Mode Current: 10μA
• 50MHz typ., 30MHz guaranteed
• Cascaded Configuration
• Extremely Fast Output Drivers Suitable for PWM
• 16-pin SOIC-150, 16-pin QFN (4x4mm) and 16-pin SSOP Package

Applications

The device is ideal for fixed- or slow-rolling displays using static or multiplexed LED matrix and dimming functions, large LED matrix displays, mixed LED display and switch monitoring, displays in elevators, public transports (underground, trains, buses, taxis, airplanes, etc.), large displays in stadiums and public areas, price indicators in retail stores, promotional panels, bar-graph displays, industrial controller displays, white good panels, emergency light indicators, and traffic signs.

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