US 12,216,164 B2
Output voltage glitch reduction in test systems
Michael E. Harrell, Colorado Springs, CO (US); Anthony Eric Turvey, Poughkeepsie, NY (US); Stefano I D'Aquino, Westford, MA (US); and Jennifer W. Pierdomenico, Temple, PA (US)
Assigned to Analog Devices, Inc., Wilmington, MA (US)
Appl. No. 17/904,935
Filed by Analog Devices, Inc., Wilmington, MA (US)
PCT Filed Feb. 24, 2021, PCT No. PCT/US2021/019372
§ 371(c)(1), (2) Date Aug. 24, 2022,
PCT Pub. No. WO2021/173638, PCT Pub. Date Sep. 2, 2021.
Claims priority of provisional application 63/114,775, filed on Nov. 17, 2020.
Claims priority of provisional application 62/980,772, filed on Feb. 24, 2020.
Prior Publication US 2023/0176110 A1, Jun. 8, 2023
Int. Cl. G01R 31/28 (2006.01); G01R 31/319 (2006.01); H03F 1/52 (2006.01); H03F 3/04 (2006.01); H03F 3/16 (2006.01)
CPC G01R 31/31924 (2013.01) [G01R 31/2834 (2013.01); H03F 1/523 (2013.01); H03F 3/04 (2013.01); H03F 3/16 (2013.01); H03F 2200/441 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A clamp circuit comprising:
an output to provide an output current at a clamped current level;
an output transistor and a replica transistor coupled as a current mirror pair, wherein the replica transistor is scaled in size to the output transistor by a size ratio;
a first current source configured to set a current in the replica transistor, wherein the output current is set at a clamped output current value that is a sum of current of the first current source and a scaled value of the current of the first current source determined according to the size ratio; and
a register circuit, wherein a register value stored in the register circuit sets the clamped output current value;
a voltage source circuit coupled to the replica transistor, and changing the register value changes voltage of the voltage source circuit to change the clamped output current value and, wherein the voltage source circuit includes a first diode connected transistor and a second diode connected transistor, wherein a current density of the first diode connected transistor is different from a current density of the second diode connected transistor, and the voltage of the voltage source is a difference in gate-to-source voltage between the first diode connected transistor and the second diode connected transistor.