Area-Efficient Capacitor-Free Low-Dropout Regulator高芯片面積效能免電容低差穩壓器
Conventionally, capacitor-free low dropout regulators (LDO) need a minimum load current to stabilize voltage regulators in normal operation. This minimum load current requirement is a major obstacle to applying capacitor-free LDO regulators in System-on-Chip (SoC) applications. Moreover, most of the regulators use an NMOS series pass transistor at the output, the dropout voltage is quite large and therefore efficiency is low.
This invention is a chip-area-efficient capacitor-free LDO based on a current-feedback frequency compensation technique. This new LDO does not require an off-chip capacitor for stability. More than that, the new regulators require a charge pump circuit to generate a voltage that is higher than the supply voltage to control the NMOS pass transistor. It significantly increases the circuit complexity and power consumption. This invention not only cost-saving, experimental results also show good load transient, line and load regulations
The invention can be widely applied in power management integrated circuits for portable electronic devices such as mobile phones, PDAs, MD player and laptop computers in the market.
1. Low voltage and high power conversion efficiency
2. Off-chip capacitor free
3. Smaller silicon area
4. Local on-chip low-dropout regulator for system-on-chip
- Power aware system in portable electronics applications
Patent Number: US7495422B2
Application Number: US2006457411A
Inventor: Mok, Kwok Tai Philip | Lau, Sai Kit | Leung, Ka Nang
Priority Date: 22 Jul 2005
Priority Number: US7495422B2
Application Date: 13 Jul 2006
Publication Date: 24 Feb 2009
IPC Current: G05F000140
US Class: 323280
Assignee Applicant: The Hong Kong University of Science & Technology
Title: Area-efficient capacitor-free low-dropout regulator
Usefulness: Area-efficient capacitor-free low-dropout regulator
Summary: Used in a system-on-chip (SoC) application.
Novelty: Low-dropout regulator for use in system-on-chip application, has current feedback block for feeding back small-signal current that is proportional to time derivative of output voltage of stage to output of another stage
Environmental/Green Technology
Natural Resource
13 Jul 2006
US 11/457411
US 7495422
TTC.PA.264S
Hong Kong
