Efficient: high-current: linear LED driver reference design for SpO2 and other medical applications
Description
This reference design provides a protected: efficient (headroom-controlled): high-current (up to 1.5 A): linear (accurate and fast) light-emitting diode (LED) driver reference design to enable peripheral capillary oxygen saturation (SpO2) and other medical applications. A typical SpO2 application drives current through LEDs. Most of these drivers are integrated with analog front-end devices and work at the typical value of 100 mA. A higher current drive is necessitated to cover wide range of human and veterinary physiology. This design enables self-calibration and uses a look-up table for headroom control to optimally drive LEDs resulting in minimum power dissipation across the control element. The design operated from an input voltage range of 1.8 V to 4.2V and enables LED currents up to 1.5 A.
Features
- Higher efficiency by providing headroom control to optimally drive LED: - Built-in self-calibration and look-up table for headroom controlDynamic adjustment of the LED supply voltage: to achieve optimal efficiency at the programmed current levelsDiagnostics (LED open: LED short: LED disconnect) and protection mechanism for fault by disconnecting the supply using e-fuseWide operating input range from 1.8 V to 5.5 V to support all battery type inputsProgrammable range selection for LED current (from 100 mA to 1.5 A)Compatible with AFE44xx series EVMs (tested with AFE4403 EVM) for driving LEDsTested with MSP430G2553 LaunchPad™ and two on-board LEDs (green and red)
Applications
- Clinical pulse oximeter
- Endoscope
- Multiparameter patient monitor
Product Categories
- Power management