Description

The ZLED7022 is a low-noise, constant-frequency charge pump DC/DC converter that can drive up to 6 LED channels, providing a programmable constant current level ranging from 1.8 mA to 20 mA per LED channel. It can also drive higher current LEDs because its current sinks can operate in parallel. Ideal for small, battery-powered applications because very few external components are needed.

The ZLED7022's Pulse Count Control (PCC) serial digital input is used to enable/disable the LEDs and set the current level (14 settings using a nearly logarithmic scale to provide a linear brightness progression). This simple, high-speed interface allows efficient real-time management of LED's via microcontrollers or control systems.

Features

• Low quiescent current in low-current shutdown mode: 1 micro amp typical, less than 2 micro amp maximum
• Integrated thermal shutdown protection prevents damage by shutting down the ZLED7022 if the die junction temperature exceeds 160°C (typical)
• Fixed charge pump switching frequency: 1MHz typical
• Soft-start feature protects against excessive inrush current during power-on
• 2x2 mm UTQFN12 package
• Voltage supply: 2.8 to 5.5VDC
• Operating temperature: -40°C to 85°C

Benefits

• Current matching accuracy: 0.9% typical
• One pin on/off or brightness control for up to 4 LEDs via a simple PCC serial interface - no PWM or additional control circuit needed
• 14 programmable current levels for achieving real-time control of effects such as LED fade-out or suddent changes in brightness
• Low EMI and back-injected noise because the charge pump is not inductor-based
• Very few external components needed for operation
• Flexible design enables diverse LED applications: up to 20 mA per channel
• LED driver family concept with low-voltage 6 channel LED driver ZLED7022

Typical Uses

• Battery operated applications
• Hand-held products
• General purpose exterior and interior LED lighting, including applications requiring low-voltage
• General purpose low-voltage industrial applications