Method and device for reliable DC-DC converting circuits
The invention discloses a DC-DC voltage converter, which includes: i) a plurality of DC voltage converter circuits connected in series and in parallel, wherein each DC voltage converter circuit includes an inductor, a control switch, a diode, and a capacitor; and a plurality of control diodes arranged in parallel with the capacitor in the DC voltage converter circuit, wherein the number of diodes ND=2N−1 where N is the number of DC voltage converter circuits and N is a positive integer; and ii) a control circuit coupled to the control switch to operate the voltage converter when one or more control switches in the DC voltage converter circuit fail; and adjusting the conversion factor (boost factor) to always be a constant k.
1 . A DC-DC step-up converter circuit, comprising:
a plurality of DC-DC boost converter stages coupled together in parallel having a common node operative to receive an input signal (V in );
a controller circuit, electrically coupled to drive said plurality of DC-DC boost stages, wherein said controller circuit drives said plurality of DC-DC boost converter stages by a plurality of control signals (SW i ) that are 180° out of phase between consecutive DC-DC boost converter stages and each stage has a gain k equals to
N
1
-
D
,
where N is the number of DC-DC boost converter stages and D is the duty cycle of said controlling signals (SW i ); wherein said duty cycle D is between 0.5 and 1.0 and N is an even positive integer number (N=2i where i is a positive non-zero integer) greater than 2 so that an output voltage (V out ) of said plurality DC-DC boost converter stage remains constant at
NVs
1
-
D
as long as at least one of said DC-DC boost converter circuits operate, wherein each of said plurality of DC-DC boost converter stages further comprises:
an inductor having a first terminal coupled to receive said input signal V in ;
an electrical fuse coupled to a second terminal of said inductor;
a switch coupled to said electrical fuse:
a diode coupled to the second terminal of said inductor;
a resistor coupled to said switch; and
a photodiode coupled to said resistor.
2 . The DC-DC step-up converter circuit of claim 1 further comprising feedback circuit operative to control said controller circuit using a reference voltage V REF .
3 . The DC-DC step-up converter circuit of claim 2 wherein wherein said feedback circuit causes said controller circuit to issue said control signals (SW i ) wherein said reference voltage (V REF ) is a difference between said output voltage (V OUT ) and a predetermined reference voltage (V OUTREF ).
4 . The DC-DC step-up converter circuit of claim 3 wherein said plurality of DC-DC boost converter stages comprises four DC-DC boost converter stages (N=4).
5 . The DC-DC step-up converter circuit of claim 4 wherein said plurality of DC-DC boost converter stage further comprises a first DC-DC boost converter stage which comprises:
a first inductor having a first terminal coupled to said input voltage V in ;
a first electrical fuse coupled to a second terminal of said first inductor;
a first switch coupled to said electrical fuse, wherein said first switch is driven by a first control voltage SW 1 ; and
a first rectifying diode coupled to the second terminal of said first inductor.
6 . The DC-DC step-up converter circuit of claim 5 wherein said first switch is selected from a semiconductor device consisting of MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor); JFET (Junction Field-Effect Transistor); MESFET (Metal-Semiconductor Field-Effect Transistor); IGBT (Insulated Gate Bipolar Transistor)—and wherein said controller circuit is a proportional integral derivative (PI) controller.
7 . The DC-DC step-up converter circuit of claim 6 wherein
said-proportional integral derivative (PI) controller characterized by a proportional constant k p , an integral gain k j , when said output voltage V out is different from said reference voltage V ref by an amount
Δ
V
V
ref
>
0.1
then adjusting said duty cycle by an amount of ΔD, wherein
Δ
D
=
k
p
e
(
t
)
+
k
i
∫
0
t
e
(
t
)
dt
,
wherein e(t) is an error signal proportional to e(t)=|V ref −V out |, and wherein k p is a preselected constant.
8 . The DC-DC step-up converter circuit of claim 7 wherein said plurality of DC-DC boost converter stage further comprises a second DC-DC boost converter stage which comprises:
a second inductor having a first terminal coupled to said input voltage V in ;
a second electrical fuse coupled to a second terminal of said second inductor;
a second switch coupled to said electrical fuse, wherein said second switch is driven by a second driving signal SW 2 that is 180° out of phase with respect to said first driving signal SW 1 ;
a first capacitor coupled to the second terminal of said second inductor;
a second diode coupled in parallel to said capacitor; and
a second rectifying diode coupled in series to said first capacitor and the anode of said second diode.
9 . The DC-DC step-up converter circuit of claim 8 wherein said second switch is selected from a semiconductor device consisting of MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor); JFET (Junction Field-Effect Transistor); MESFET (Metal-Semiconductor Field-Effect Transistor); IGBT (Insulated Gate Bipolar Transistor).
10 . The DC-DC step-up converter circuit of claim 9 , wherein said second DC-DC boost converter stage further comprises:
a second resistor coupled to said second switch; and
a second photo diode coupled to said second resistor.
11 . The DC-DC step-up converter circuit of claim 10 wherein said plurality of DC-DC boost converter stage further comprises a third DC-DC boost converter stage which comprises:
a third inductor having a first terminal coupled to said input voltage V in ;
a third electrical fuse coupled to a second terminal of third second inductor;
a third switch coupled to said electrical fuse, wherein said third switch is driven by a third driving signal SW 3 that is 180° out of phase with respect to said second driving signal SW 2 ;
a second capacitor coupled to the second terminal of said third inductor;
a second diode coupled in parallel to said second capacitor; and
a second rectifying diode coupled in series to said second capacitor and the anode of said second diode.
12 . The DC-DC step-up converter circuit of claim 11 wherein said third switch is selected from a semiconductor device consisting of MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor); JFET (Junction Field-Effect Transistor); MESFET (Metal-Semiconductor Field-Effect Transistor); IGBT (Insulated Gate Bipolar Transistor).
13 . The DC-DC step-up converter circuit of claim 12 , wherein said third DC-DC boost converter stage further comprises:
a third resistor coupled to said third switch; and
a third diode coupled to said third resistor.
14 . The DC-DC step-up converter circuit of claim 13 wherein said plurality of DC-DC boost converter stage further comprises a fourth DC-DC boost converter stage which comprises:
a fourth inductor having a first terminal coupled to said input voltage V in ;
a fourth electrical fuse coupled to a second terminal of said fourth inductor;
a fourth switch coupled to said electrical fuse, wherein said fourth switch is driven by a fourth driving signal SW 4 that is 180° out of phase with respect to said third driving signal SW 3 ;
a third capacitor coupled to the second terminal of said fourth inductor;
a third diode coupled in parallel to said third capacitor; and
a fourth rectifying diode coupled in series to said third capacitor and the anode of said second directional diode.
15 . The DC-DC step-up converter circuit of claim 14 wherein said fourth switch is selected from a semiconductor device consisting of MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor); JFET (Junction Field-Effect Transistor); MESFET (Metal-Semiconductor Field-Effect Transistor); IGBT (Insulated Gate Bipolar Transistor).
16 . The DC-DC step-up converter circuit of claim 15 , wherein said second DC-DC boost converter stage further comprises:
a fourth resistor coupled to said fourth switch; and
a fourth diode coupled to said fourth resistor.