Abstract:
This paper presents a low-power wide-swing current mirror light emitting diode (LED) driver designed for an ultra-low power pulse oximeter. The presented driver can regul...Show MoreMetadata
Abstract:
This paper presents a low-power wide-swing current mirror light emitting diode (LED) driver designed for an ultra-low power pulse oximeter. The presented driver can regulate red (Forward Voltage= 2.2 V) and infrared (Forward Voltage = 1.55 V) LEDs with a low supply voltage battery. The proposed new design relies on a clock-based strategy along with a wide-swing current mirror topology providing an improved dynamic range. The proposed LED driver allows the independent control of the driving current of each LED. By varying the duty cycle of a pulse wave modulation (PWM) signal, the operating and idle times of the circuits can be modulated to regulate the current. Using a 1% duty cycle and a 100 Hz PWM signal frequency, the estimated power consumption is 0.92 mW with a typical driving current of 14 mA for the red LED and a typical driving current of 20 mA for the infrared LED. The circuit is designed using a CMOS TSMC 130 nm process.
Published in: 2023 21st IEEE Interregional NEWCAS Conference (NEWCAS)
Date of Conference: 26-28 June 2023
Date Added to IEEE Xplore: 07 August 2023
ISBN Information: