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A voltage generation circuit for generating a read-back voltage in response to a supply voltage and a reference voltage. The voltage generation circuit includes a comparator configured to receive the supply voltage and the reference voltage. The voltage generation circuit activates a select signal i

A voltage generation circuit for generating a read-back voltage in response to a supply voltage and a reference voltage. The voltage generation circuit includes a comparator configured to receive the supply voltage and the reference voltage. The voltage generation circuit activates a select signal if the supply voltage has a predetermined relationship with respect to the reference voltage, and de-activates the select signal if the supply voltage does not exhibit the predetermined relationship with respect to the reference voltage. An adjustable voltage divider circuit is coupled to receive the supply voltage and the select signal. The adjustable voltage divider circuit is configured in response to the select signal to provide an output voltage that is a first percentage of the supply voltage if the select signal is activated, and provide an output voltage that is a second percentage of the supply voltage if the select signal is de-activated.

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1. A voltage generation circuit comprising:a comparator configured to receive and a supply voltage and a reference voltage and to perform a comparison therebetweeen, and in response, activate a select signal if the supply voltage has a predetermined relationship with respect to the reference voltage

1. A voltage generation circuit comprising:a comparator configured to receive and a supply voltage and a reference voltage and to perform a comparison therebetweeen, and in response, activate a select signal if the supply voltage has a predetermined relationship with respect to the reference voltage, and de-activate the select signal if the supply voltage does not exhibit the predetermined relationship with respect to the reference voltage; andan adjustable voltage divider circuit coupled to receive the supply voltage and the select signal, wherein the adjustable voltage divider circuit is configured in response to the select signal to provide an output voltage that is a first percentage of the supply voltage if the select signal is activated, and provide an output voltage that is a second percentage of the supply voltage if the select signal is de-activated. 2. The voltage generation circuit of claim 1, further comprising an output driver configured to receive the output voltage. 3. The voltage generation circuit of claim 2, further comprising an address line coupled to an output terminal of the output driver, wherein the output driver provides the output voltage as a read-back voltage on the address line. 4. The voltage generation circuit of claim 1, wherein the output driver further comprises a current limiting output stage configured to soften a rising edge of the output voltage. 5. The voltage generation circuit of claim 4, wherein the current limiting output stage comprises a resistor coupled between an output terminal of the output driver and a terminal that provides the supply voltage. 6. The voltage generation circuit of claim 1, further comprising a bandgap voltage generator configured to generate a bandgap voltage, wherein the reference voltage is derived from the bandgap voltage. 7. The voltage generation circuit of claim 6, further comprising a voltage divider circuit coupled to the bandgap voltage generator, wherein the voltage divider circuit provides the reference voltage in response to the bandgap voltage. 8. The voltage generation circuit of claim 1, wherein the predetermined relationship is defined by the supply voltage being less than the reference voltage. 9. The voltage generation circuit of claim 8, wherein the first percentage is greater than the second percentage. 10. The voltage generation circuit of claim 9, wherein the first percentage is about 95 to 100 percent, and the second percentage is less than 95 percent. 11. The voltage generation circuit of claim 1, wherein the adjustable voltage divider circuit comprises:a first resistor and a pass transistor coupled in series between a supply voltage terminal coupled to receive the supply voltage and an output terminal configured to provide the output voltage, the pass transistor having a gate coupled to receive the select signal; anda second resistor coupled between the output terminal and a second voltage supply terminal coupled to receive a second supply voltage, wherein the output voltage is provided on the output terminal. 12. The voltage generation circuit of claim 11, wherein the adjustable voltage divider circuit further comprises a third resistor coupled between the supply voltage terminal and the output terminal. 13. The voltage generation circuit of claim 11, wherein the adjustable voltage divider circuit further comprises a third resistor and a second pass transistor coupled in series between the supply voltage terminal and the output terminal, the second pass transistor having a gate coupled to receive the inverse of the select signal. 14. The voltage generation circuit of claim 1, further comprising:a second comparator configured to receive the supply voltage and a second reference voltage, and in response, activate a second select signal if the supply voltage has a predetermined relationship with respect to the second reference voltage, and de-activate the second select signal if the supply voltage does not exhibit the predetermined relat ionship with respect to the second reference voltage;wherein the adjustable voltage divider circuit is configured in response to the first and second select signals to provide an output voltage that is a first percentage of the supply voltage if the select signal is activated and the second select signal is de-activated, and provide an output voltage that is a second percentage of the supply voltage if the select signal and the second select signal are both activated. 15. A method of generating an output voltage in response to a supply voltage and a reference voltage, the method comprising:comparing the supply voltage with the reference voltage;activating a select signal if the supply voltage is less than the reference voltage;de-activating the select signal if the supply voltage is greater than the reference voltage;providing an output voltage that is a first percentage of the supply voltage if the select signal is activated; andproviding an output voltage that is a second percentage of the supply voltage if the select signal is de-activated, wherein the first percentage is greater than the second percentage. 16. The method of claim 15, further comprising driving the output voltage as a read-back voltage onto an address line. 17. The method of claim 15, further comprising deriving the reference voltage from a bandgap voltage generator. 18. The method of claim 15, wherein the first percentage is about 95 to 100 percent, and the second percentage is less than 95 percent. 19. The method of claim 15, further comprising enabling a first leg of a voltage divider circuit when the select signal is activated. 20. The method of claim 19, further comprising enabling a second leg of a voltage divider circuit when the select signal is de-activated. 21. The method of claim 15, further comprising comparing the supply voltage with a second reference voltage, wherein the first reference voltage is greater than the second reference voltage;activating a second select signal if the supply voltage is less than the second reference voltage;de-activating the second select signal if the supply voltage is greater than the second reference voltage;providing an output voltage that is the first percentage of the supply voltage if the select signal is activated and the second select signal is de-activated;providing an output voltage that is the second percentage of the supply voltage if the select signal and the second select signal are de-activated; andproviding an output voltage that is a third percentage of the supply voltage if the select signal and the second select signal are activated, wherein the third percentage is greater than the first percentage. 22. A voltage generation circuit for generating an output voltage, the voltage generation circuit comprising:a first comparator configured to receive a first supply voltage and a first reference voltage, and in response, activate a first select signal if the first supply voltage has a first predetermined relationship with respect to the first reference voltage, and de-activate the first select signal if the first supply voltage does not exhibit the first predetermined relationship with respect to the first reference voltage;a second comparator configured to receive a second supply voltage and a second reference voltage and in response, activate a second select signal if the second supply voltage has a second predetermined relationship with respect to the second reference voltage, and de-activate the second select signal if the second supply voltage does not exhibit the second predetermined relationship with respect to the second reference voltage; andan adjustable voltage divider circuit coupled to receive the first select signal and the second select signal, wherein the adjustable voltage divider circuit is configured to provide an output voltage that is a first percentage of a fifth voltage if the first select signal is activated, and provide an output voltage that is a second percentage of a sixth voltage if the second select signal is activated.