Sense amplifiers with high voltage swing
View Patent ↗A sense amplifier includes a reference voltage generator for generating a reference output voltage and a core output voltage generator for generating a core output voltage. The core output voltage generator includes a core front-end stage and a core back-end stage or includes a plurality of amplifier transistors each conducting a portion of a core current through a current conducting device such as core cell. The sizes and/or connections of transistors of such components result in high voltage swing and thus high sensitivity of the sense amplifier.
1. A sense amplifier comprising:
a reference voltage generator for generating a reference output voltage;
a core output voltage generator for generating a core output voltage, the core output voltage generator including:
a core front-end stage coupled to a current conducting device for converting a current through the current conducting device to a core bit voltage; and
a core back-end stage coupled to the core front-end stage for converting the core bit voltage to the core output voltage having higher voltage swing from the core bit voltage;
a comparator for generating an output signal from comparing the reference output voltage with the core output voltage;
a plurality of core output voltage generators; and
a plurality of comparators with each comparator being coupled to the reference output voltage generator for generating a respective output signal from comparing the reference output voltage to a respective core output voltage generated by a respective one of the core output voltage generators.
2. A sense amplifier comprising:
a reference voltage generator for generating a reference output voltage;
a core output voltage generator for generating a core output voltage, the core output voltage generator including:
a core front-end stage coupled to a current conducting device for converting a current through the current conducting device to a core bit voltage; and
a core back-end stage coupled to the core front-end stage for converting the core bit voltage to the core output voltage having higher voltage swing from the core bit voltage;
an amplifier regulation transistor having a drain coupled to the current conducting device at a node having the core bit voltage generated thereon and having a source coupled to a power supply; and
a core feed-back regulator coupled to a gate and the drain of the amplifier regulation transistor for maintaining the core bit voltage.
3. The sense amplifier of claim 2 , wherein the core back-end stage includes:
a first amplifier transistor having a gate coupled to the gate of the amplifier regulation transistor, and having a source coupled to the power supply; and
a second amplifier transistor having a drain coupled to the drain of the first amplifier transistor, and having a gate and the drain coupled together at an output node with the core output voltage generated thereon.
4. The sense amplifier of claim 2 , wherein the core back-end stage includes:
a first amplifier transistor having a gate coupled to the gate of the amplifier regulation transistor, and having a source coupled to the power supply; and
an amplifier bias resistor coupled between a drain of the first amplifier transistor and a ground node.
5. The sense amplifier of claim 2 , wherein the core back-end stage includes:
a first amplifier transistor having a gate coupled to the gate of the amplifier regulation transistor, and having a source coupled to the power supply; and
a second amplifier transistor having a gate with the reference output voltage applied thereon, and having a source coupled to a ground node, and having a drain coupled to a drain of the first amplifier transistor at an output node with the core output voltage generated thereon.
6. The sense amplifier of claim 2 , wherein the core back-end stage includes:
a first amplifier transistor having a gate coupled to the gate of the amplifier regulation transistor, and having a source coupled to the power supply; and
a second amplifier transistor having a gate with the reference output voltage applied thereon, and having a source coupled to a ground node via an amplifier noise immunity resistor, and having a drain coupled to a drain of the first amplifier transistor at an output node with the core output voltage generated thereon.
7. The sense amplifier of claim 2 , wherein the reference voltage generator includes:
a reference front-end stage coupled to a reference cell for converting a reference current through the reference cell to a reference bit voltage; and
a reference back-end stage coupled to the reference front-end stage for converting the reference bit voltage to the reference output voltage.
8. The sense amplifier of claim 7 , wherein the reference front-end stage includes:
a reference regulation transistor having a drain coupled to the reference cell at a node having the reference bit voltage generated thereon and having a source coupled to the power supply.
9. The sense amplifier of claim 7 , wherein the reference front-end stage further includes:
a reference feed-back regulator coupled to a gate and the drain of the reference regulation transistor for maintaining the reference bit voltage.
10. The sense amplifier of claim 7 , wherein the reference back-end stage includes:
a first reference transistor having a gate coupled to the gate of the reference regulation transistor and having a source coupled to the power supply; and
a second reference transistor having a drain coupled to a drain of the first reference transistor, and having a gate and the drain coupled together at an output node with the reference output voltage generated thereon.
11. The sense amplifier of claim 8 , wherein the reference back-end stage includes:
a first reference transistor having a gate coupled to the gate of the reference regulation transistor and having a source coupled to the power supply; and
a second reference transistor having a drain coupled to a drain of the first reference transistor, having a gate and the drain coupled together at an output node with the reference output voltage generated thereon, and having a source coupled to a ground node.
12. The sense amplifier of claim 8 , wherein the reference back-end stage includes:
a first reference transistor having a gate coupled to the gate of the reference regulation transistor and having a source coupled to the power supply; and
a reference bias resistor coupled between a drain of the first reference transistor and a ground node.
13. The sense amplifier of claim 8 , wherein the reference back-end stage includes:
a first reference transistor having a gate coupled to the gate of the reference regulation transistor and having a source coupled to the power supply; and
a second reference transistor having a drain coupled to a drain of the first reference transistor, having a gate and the drain coupled together at an output node with the reference output voltage generated thereon, and having a source coupled to a ground node via a reference noise immunity resistor.
14. The sense amplifier of claim 2 , further comprising:
a comparator for generating an output signal from comparing the reference output voltage with the core output voltage.
15. The sense amplifier of claim 2 , wherein the current conducting device is a core cell of a memory device.
16. The sense amplifier of claim 2 , wherein the core front-end stage includes the amplifier regulation transistor.