Abstract
The importance of energy-constrained processors continues
to grow especially for ultra-portable sensor-based
platforms for the Internet-of-Things (IoT). Processors
for these IoT applications primarily operate at
near-threshold (NT) voltages and have multiple power
modes. Achieving high conversion efficiency within the
DC-DC converter that supplies these processors is
critical since energy consumption of the DC-DC/processor
system is proportional to the DC-DC converter efficiency.
The DC-DC converter must maintain high efficiency over a
large load range generated from the multiple power modes
of the processor. This paper presents a fully integrated
step-down self-oscillating switched-capacitor DC-DC
converter that is capable of meeting these challenges.
The area of the converter is 0.0104 mm2 and is designed
in 28 nm ultra-thin body and buried oxide fully-depleted
SOI (UTBB FD-SOI). Back-gate biasing within FD-SOI is
utilized to increase the load power range of the
converter. With an input of 1 V and output of 460 mV,
measurements of the converter show a minimum efficiency
of 75% for 79 nW to 200 µW loads. Measurements with an
off-chip NT processor load show efficiency up to 86%. The
converter's large load power range and high efficiency
make it an excellent fit for energy-constrained
processors.
| Original language | English |
|---|---|
| Article number | 17 |
| Journal | Journal of Low Power Electronics and Applications |
| Volume | 6 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2016 |
| MoE publication type | A1 Journal article-refereed |
Keywords
- switched-capacitor
- DC-DC converter
- near-threshold voltage
- self-oscillating
- ultra-thin body and buried oxide fully-depleted SOI (UTBB FD-SOI)
- fully-depleted SOI (UTBB FD-SOI)
- sub-threshold
- low voltage regulation
- OtaNano
