Abstract
This paper presents a low power and wide dynamic range optical receiver dedicated to the frequency domain near infrared spectroscopy (FD-NIRS). The proposed optical receiver is fabricated using a 0.18 μm CMOS technology with a 0.5 mm 2 integrated PIN photodiode (PD). This large area of the PD is necessary to collect a sufficient amount of the weak optical power which is reflected from the human scalp. Moreover, an automatic gain control (AGC) is used to account for the large individual variations and to enable connecting different inter-optodes separations to the same amplifier chain. This adopted AGC extends the maximum overloading input photocurrent of the optical receiver to 6.4 μApp resulting in a 17.04 dB dynamic range extension and a total dynamic range of 50.1 dB. The chip consumes 2.35 mW of power, has an integrated input referred noise current of 20 nArms, a maximum gain of 109.6 dBΩ, and a 10.7 MHz bandwidth.
Original language | English |
---|---|
Pages (from-to) | 92-97 |
Number of pages | 6 |
Journal | Microelectronics Journal |
Volume | 85 |
DOIs | |
Publication status | Published - Mar 2019 |
Externally published | Yes |
Keywords
- Automatic gain control
- Near infrared spectroscopy
- Optical receiver
- Regulated inverter cascode
- Transimpedance amplifier
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Electrical and Electronic Engineering