Sense amplifier driving device
View Patent ↗A semiconductor memory device includes a memory cell, a bit line connected to the memory cell, and a sense amplifier. The sense amplifier is connected to the bit line, receives a first control signal, and detects and amplifies a bit line signal of the bit line. The sense amplifier includes a precharge device that is turned on or turned off based on a read control signal, and a transistor output unit that outputs an output voltage based on the bit line signal when the precharge device is turned off.
1. A method for sensing one time programmable (OTP) memory cells connected to a bit line, the method comprising:
receiving a first control signal by a sense amplifier;
detecting a bit line signal of the bit line by the sense amplifier;
amplifying the bit line signal by the sense amplifier;
receiving, by the sense amplifier, a first operation voltage from a voltage generator;
outputting the first operation voltage or a ground voltage to a second level shifter based on the bit line signal of the bit line.
2. The method of claim 1 , wherein the sense amplifier comprises a precharge device for receiving the first operation voltage and a transistor output unit for outputting the first operation voltage or the ground voltage.
3. The method of claim 2 , wherein the transistor output unit comprises a pull-up device and a pull-down device, the method further comprising:
connecting the pull-up device and the pull-down device in series; and
coupling the pull-up device and the pull-down device between the first operation voltage and a ground voltage.
4. The method of claim 2 , further comprising:
turning the precharge device on or turned off based on a read control signal; and
outputting, by the transistor output unit, an output voltage based on the bit line signal when the precharge device is turned off.
5. The method of claim 4 , further comprising:
outputting, by the second level shifter, a first supply voltage or the ground voltage based on the output voltage of the transistor output unit.
6. The method of claim 4 , further comprising:
converting, by a first level shifter, the read control signal to a read control voltage; and
providing the read control voltage to the precharge device.
7. The method of claim 6 , further comprising:
providing the first control signal to the precharge device.
8. The method of claim 1 , wherein the voltage generator receives a first supply voltage, generates the first operation voltage based on the first supply voltage, and supplies the first operation voltage to the sense amplifier.
9. The method of claim 8 , wherein the first operation voltage is higher than the first supply voltage.
10. The method of claim 9 , wherein the first operation voltage is about 2V, and the first supply voltage is less than about 1.5V.
11. The method of claim 1 , wherein the memory cell is a programmed cell, the method further comprising:
discharging the bit line voltage of the bit line connected to the programmed cell to a ground level based on the first control signal.
12. The method of claim 1 , wherein the memory cell is an unprogrammed cell, the method further comprising:
charging the bit line voltage of the bit line connected to the unprogrammed cell to the first operation voltage based on the first control signal.