Efficient current, voltage, and power sensing are critical blocks for power management, switching regulators, maximum power point tracking (MPPT) circuit, and motor control. This paper presents a standard CMOS and low-power current-to-digital converter (IDC) that senses the current flowing at high-voltage nodes. The proposed sensor uses a CMOS-switched capacitor circuit to sense a dc-dc converter output current and gives digital output without an analog-to-digital converter (ADC), or the need for high-voltage technologies. Compared to the resistor-based current-sensing methods that require current-to-voltage circuit, gain block, and an ADC converter, the proposed sensor is a low-power integrated circuit that achieves high resolution, lower complexity, and lower power consumption. The IDC circuit is fabricated on a 5 V, 0.7 μm, and three metal CMOS technology and occupied less than 10% area (1 mm2 area) compared to other sensors. It consumes 18 mW that is less than 40% power consumed by other sensors, and its current measurement error is below 0.4%. The proposed IDC circuit has been characterized as standalone and with a boost dc-dc regulator and MPPT for photovoltaic systems.
- Current sensor
- data converter
- dc-dc converter
- maximum power point tracking (MPPT)
- photovoltaic (PV)
ASJC Scopus subject areas
- Electrical and Electronic Engineering