Guidelines on the Switch Transistors Sizing Using the Symbolic Description for the Cross-Coupled Charge Pump

Complex model description and main capacitor sizing for the cross-coupled charge pump synthesis process

“…The goal is to achieve such an equivalent internal impedance so that the pump provides the required output voltage at the defined load current I L . As it is well known, the solution from this point of view is ambiguous [4] because low impedance can be ensured by setting one or more of the other pump parameters (the number of stages, clock frequency, etc). However, not only the voltage gain is a design criterion.…”

“…Easy integrability is among the main advantages of DC/DC converters without inductors. Modern architecture of the cross-coupled charge pump [1] with driving feedback circuit was presented in detail from theoretical analysis [2,3] through the simulations of real properties [4,5] to the mathematical model [6,7], which is including important properties of the circuit structure. The pump stage has been described as an analog subcircuit, labeled X n and X L see Fig.…”

“…As a result of this, formulas for the circuit design were derived -CMOS inverter [9], switch transistor and diode transistor sizing [4], including the verification of all formulae in the professional simulator software. Using the state-space description, the creation model also allows estimating static and dynamic parameters in Nstage charge pump [7] through the programme procedure.…”

“…Applying specified design criteria, main capacitor value can be found based on the time response characteristics of the first and last pump stage that is additionally connected with the diode transistors. The diode transistor sizing is modified [4] for that task. Finally, the load capacitor sizing for the maximum value of the output ripple voltage is mentioned.…”

A Program Procedure for Estimation of the Cross-Coupled Charge Pump Properties

“…Firstly, the strategy of the solution through the state description of the system will be explained. The main part deals with principle of the computational algorithm which core is operating with previously derived analytic formulae of the analog blocks ( [3], [6]). Algorithm is implemented in Maple SW and achieve results are compared with the full transistor-level properties of the charge pump, which are simulated in professional design environment ELDO.…”