No abstract

No abstract

This paper introduces a novel low-power digital future, are expected to run at frequencies beyond 10 MHz. In controller for high frequency dc-dc switch-mode power supplies addition, the demonstrated systems do not offer a digital (SNIPS) that is well-suited for integration in power management solution for pulse-frequency modulation (PFM), which at light systems of small handheld devices. The controller operates at loads largely improves SMPS efficiency [3]. programmable constant switching frequencies up to 20 MHz and In this paper we present a new low-power architecture that can change mode of operation to improve the overall SNIPS allows integration of digitally controlled SMPS in the existing efficiency. The key elements of the controller are a high and upcoming handheld devices. The controller, shown in frequency digital pulse-width modulator (DPWM), based on a . . . a segmented ring oscillator, and a signal-race based digital pulseFig. , operates at programmable switchMg frequencies up to frequency modulator (DPFM). The controller is implemented in 20 MHz and can switch between PWM and PFM voltage a standard CMOS 0.18 ,Im process and its operation verified regulationmodes. both through simulations and experiments.

No abstract

This paper presents an integrated dc-dc converter with an output voltage of 1 V for portable applications. A hybrid peak current-mode control-scheme is demonstrated, where the voltage-loop compensation is achieved in the digital domain, while the current-regulation loop has a more traditional analog implementation. The main contribution of this work is the novel DAC architecture, which was developed specifically to achieve fast transient-response without needing clock frequencies beyond fs, or expensive signal processing. Unlike the previous approach, based on an adaptive ΔΣ DAC, the charge-pump (CP) DAC is capable of rapidly increasing the current-command in a singlecycle during load-steps. In addition to a low steady-state currentconsumption of 3 μA, the CP-DAC has a guaranteed monotonic transfer characteristic and simplifies the overall system architecture. The resulting system solution achieves dynamic response comparable to state-of-the-art analog current-mode solutions, without using a power-hungry controller, or quantizing the inductor current. A custom IC, which was fabricated in a 0.18 μm CMOS process with 5 V compatible transistors, achieves a response-time of 4 μs at fs = 3 MHz and Vout = 1 V, for a 200 mA load-step. The active area of the controller is only 0.077 mm 2 , and the total controller current-draw, which is heavily dominated by the on-chip senseFET current-sensor, is below 0.5 % of the load current at Iout= 50 mA.

No abstract

No abstract

No abstract