A 450-mV Single-Fuel-Cell Power Management Unit With Switch-Mode Quasi-${\rm V}^2$ Hysteretic Control and Automatic Startup on 0.35-$\mu$m Standard CMOS Process

This paper presents a power management unit (PMU) for emerging applications powered by low-voltage single direct methanol fuel cell (DMFC). A subthreshold startup scheme and its circuit implementation are proposed to enable low-voltage self-startup feature. A boost switching converter with a switch-mode, quasi-V2 hysteretic control is designed for power conditioning. The PMU is implemented on a standard 0.35-μm CMOS process with VTN/VTP of 0.55 V/ -0.75 V, respectively. Experimental results prove that the PMU automatically starts up with 450-mV single DMFC input. The output voltage of the PMU is well regulated with below 25 mV ripple. With an output power ranging from 20 to 200 mW, an average efficiency above 85.2% is obtained, with a maximum of 89.4%. Load transient recovery times are 11.6 μs/4.2 μs, respectively, in response to the step-up and step-down load changes between 10 and 100 mA.

[1]  Kaushik Roy,et al.  Ultra-low power digital subthreshold logic circuits , 1999, Proceedings. 1999 International Symposium on Low Power Electronics and Design (Cat. No.99TH8477).

[2]  Chi-Ying Tsui,et al.  A pseudo-CCM/DCM SIMO switching converter with freewheel switching , 2002, 2002 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.02CH37315).

[3]  James Larminie,et al.  Fuel Cell Systems Explained , 2000 .

[4]  James Larminie,et al.  Fuel Cell Systems Explained: Larminie/Fuel Cell Systems Explained , 2003 .

[5]  S. Takayasu,et al.  0.18-V Input Charge Pump with Forward Body Biasing in Startup Circuit using 65nm CMOS , 2010 .

[6]  Takayasu Sakurai,et al.  A 95mV-startup step-up converter with Vth-tuned oscillator by fixed-charge programming and capacitor pass-on scheme , 2011, 2011 IEEE International Solid-State Circuits Conference.

[7]  Anantha Chandrakasan,et al.  A Battery-Less Thermoelectric Energy Harvesting Interface Circuit With 35 mV Startup Voltage , 2010, IEEE Journal of Solid-State Circuits.

[8]  Lei Zhang,et al.  A review of anode catalysis in the direct methanol fuel cell , 2006 .

[9]  Kai Strunz,et al.  A 20 mV Input Boost Converter With Efficient Digital Control for Thermoelectric Energy Harvesting , 2010, IEEE Journal of Solid-State Circuits.

[10]  Chi K. Tse,et al.  Development of a maximum-power-point tracking algorithm for direct methanol fuel cell and its realization in a fuel cell/supercapacitor hybrid energy system , 2011, 8th International Conference on Power Electronics - ECCE Asia.

[11]  Koichi Ishida,et al.  Startup Techniques for 95 mV Step-Up Converter by Capacitor Pass-On Scheme and ${\rm V}_{\rm TH}$-Tuned Oscillator With Fixed Charge Programming , 2012, IEEE Journal of Solid-State Circuits.

[12]  Siti Kartom Kamarudin,et al.  Overview on the application of direct methanol fuel cell (DMFC) for portable electronic devices , 2009 .

[13]  Wing-Hung Ki,et al.  Ultra Fast Fixed-Frequency Hysteretic Buck Converter With Maximum Charging Current Control and Adaptive Delay Compensation for DVS Applications , 2008, IEEE Journal of Solid-State Circuits.

[14]  R. M. Bass,et al.  Eliminating the effects of the right-half plane zero in fixed frequency boost converters , 1998, PESC 98 Record. 29th Annual IEEE Power Electronics Specialists Conference (Cat. No.98CH36196).

[15]  S. Srinivasan,et al.  International activities in DMFC R&D: status of technologies and potential applications , 2004 .

[16]  Detlef Stolten,et al.  Development of a compact 500 W class direct methanol fuel cell stack , 2002 .

[17]  T.Y. Man,et al.  A 0.9-V Input Discontinuous-Conduction-Mode Boost Converter With CMOS-Control Rectifier , 2008, IEEE Journal of Solid-State Circuits.

[18]  N. Keskar,et al.  Self-stabilizing, integrated, hysteretic boost DC-DC converter , 2004, 30th Annual Conference of IEEE Industrial Electronics Society, 2004. IECON 2004.

[19]  Saibal Mukhopadhyay,et al.  Leakage current mechanisms and leakage reduction techniques in deep-submicrometer CMOS circuits , 2003, Proc. IEEE.

[20]  Wing-Hung Ki,et al.  Digitally assisted quasi-V2 hysteretic buck converter with fixed frequency and without using large-ESR capacitor , 2009, 2009 IEEE International Solid-State Circuits Conference - Digest of Technical Papers.