Patent ID: 7906995

Claim:
An apparatus comprising: a first bipolar junction transistor (BJT) differential pair having a first BJT and a second BJT; a second BJT differential pair having a third BJT and a fourth BJT, wherein the collector and base of the third BJT are respectively coupled to the collector and base of the first BJT, and wherein the collector and base of the of the fourth BJT are respectively coupled to the collector and base of the second BJT, and wherein the bases of first, second, third, and fourth BJTs receive an input clock signal; a first clamp having a fifth BJT and a sixth BJT, wherein the emitters of the fifth and sixth BJTs are coupled to the collectors of the first and third BJTs, and wherein the base of the fifth BJT is adapted to receive a low clamping voltage, and wherein the sixth BJT is adapted to receive a high clamping voltage, and wherein the first clamp is coupled to the collectors of the first, second, third, and fourth BJTs; and a second clamp having a seventh BJT and an eighth BJT, wherein the emitters of the seventh and eight BJTs are coupled to the collectors of the second and fourth BJTs, and wherein the base of the seventh BJT is adapted to receive the low clamping voltage, and wherein the eighth BJT is adapted to receive the high clamping voltage, and wherein the second clamp is coupled to the collectors of the first, second, third, and fourth BJTs.