Boosted voltage generator
View Patent ↗The present invention provides a boosted voltage generator of a semiconductor device where a boosted voltage efficiency and drivability at a target boosted voltage level can be evaluated accurately by employing an enable signal generator. The boosted voltage generator includes a boosted voltage pad; a level detection means for detecting whether or not a present boosted voltage reaches a target boosted voltage level; an oscillation means for performing an oscillation mode in response to a signal outputted from the level detection means; a charge pumping means for outputting a level-controlled boosted voltage in response to a signal outputted from the oscillation means; and an enable signal generation means for operating the oscillation means in response to a signal outputted from the level detection means.
1. A boosted voltage generator comprising:
a level detection means for detecting whether or not a present boosted voltage reaches a target boosted voltage level;
an oscillation means for performing an oscillation mode in response to a signal outputted from the level detection means;
a charge pumping means for outputting a level-controlled boosted voltage in response to a signal outputted from the oscillation means;
an enable signal generation means for operating the level detection means in response to a test mode boosted voltage rising signal and a test mode boosted voltage falling signal;
a first fuse for modulating an oscillation period of the oscillation means according to a comparison result between measured and simulated efficiencies; and
a second fuse for modulating a pumping intensity of the charge pumping means according to the comparison result.
2. The boosted voltage generator as recited in claim 1 , wherein, in a test mode, the test mode boosted voltage rising signal is used for raising a level of the level-controlled boosted voltage to a predetermined level and the test mode boosted falling signal is used for lowering the level of the level-controlled boosted voltage to a predetermined level.
3. The boosted voltage generator as recited in claim 2 , wherein a target boosted voltage is applied to a boosted voltage pad from a test apparatus in a test mode.
4. The boosted voltage generator as recited in claim 3 , wherein the enable signal generation means includes a NAND gate where the test mode boosted voltage rising signal and the test mode boosted falling signal are inputted.
5. The boosted voltage generator as recited in claim 1 , wherein a target boosted voltage is applied to the boosted voltage pad from a test apparatus in the test mode.
6. The boosted voltage generator as recited in claim 5 , wherein the enable signal generation means includes a NAND gate where the test mode boosted voltage rising signal and the test mode boosted falling signal are inputted.
7. The boosted voltage generator as recited in claim 1 , wherein the oscillation means includes a ring oscillator.
8. A boosted voltage generator comprising:
a level detector arranged to generate a signal indicative of a present boosted voltage reaching a target boosted voltage level;
an oscillator arranged to perform an oscillation mode responsive to the level detector signal;
a charge pump arranged to generate a level-controlled boosted voltage responsive to a signal from the oscillator;
an enable signal generator arranged to transmit a signal to the level detector responsive to a test mode boosted voltage rising signal and a test mode boosted voltage falling signal;
an oscillator fuse arranged to modulate an oscillation period of the oscillator, wherein the oscillator fuse is further arranged to be modified based on a comparison result between a measured and a simulated efficiency; and
a charge pump fuse arranged to modulate a pumping intensity of the charge pump, wherein the charge pump fuse is further arranged to be modified based on the comparison result.