Patent ID: 9654087
Date: 2017-05-16
CPC Classifications: H03K

Claim:
1. A high voltage level shifter configured to translate an input signal from a low-side low voltage domain to a high-side low voltage domain, the high voltage level shifter comprising: a first high voltage level shifter device, wherein the first high voltage level shifter device comprises a first high-side terminal, a first low-side terminal, and a first control terminal, and wherein the first control terminal is configured to control a first current flowing into the first high-side terminal to the first low-side terminal; a second high voltage level shifter device, wherein the second high voltage level shifter device comprises a second high-side terminal, a second low-side terminal, and a second control terminal, and wherein the second control terminal is configured to control a second current flowing into the second high-side terminal to the second low-side terminal; a low-side control circuit configured to drive the first control terminal and the second control terminal, wherein the low-side control circuit is further configured to drive, in response to the input signal, one of the first high voltage level shifter device and the second high voltage level shifter device to an active state while the other of the first high voltage level shifter device and the second high voltage level shifter device remains in an inactive state; a high-side receiver circuit configured to set a state of a high-side output signal in response to the one of the first high voltage level shifter device and the second high voltage level shifter device driven in the active state; wherein the high-side receiver circuit is configured to monitor a first difference between the first current flowing into the first high-side terminal of the first high voltage level shifter device and the second current flowing into the second high-side terminal of the second high voltage level shifter device; and wherein the low-side control circuit is configured to control a concomitant control terminal of the first control terminal and the second control terminal corresponding to the one of the first high voltage level shifter device and the second high voltage level shifter device driven in the active state in response to a second difference between the first current and the second current monitored flowing out of the first low-side terminal and the second low-side terminal.