US 11,705,888 B2
ZQ calibration using current source
Yasuo Satoh, Tsukuba (JP); Hiroki Takahashi, Inagi (JP); Shuichi Tsukada, Sagamihara (JP); and Yuan He, Boise, ID (US)
Assigned to Micron Technology, Inc., Boise, ID (US)
Filed by Micron Technology, Inc., Boise, ID (US)
Filed on Nov. 2, 2020, as Appl. No. 17/86,792.
Application 17/086,792 is a continuation of application No. 16/598,964, filed on Oct. 10, 2019, granted, now 10,886,898.
Prior Publication US 2021/0111706 A1, Apr. 15, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. H03K 19/00 (2006.01); H03H 11/54 (2006.01); H03H 11/28 (2006.01)
CPC H03H 11/54 (2013.01) [H03H 11/28 (2013.01); H03K 19/0005 (2013.01); G11C 2207/2254 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An apparatus, comprising:
a current source circuit configured to generate a reference current that is at a constant value for a predetermined temperature range;
a reference calibration circuit configured to generate a calibration current based on the reference current; and
a terminal calibration circuit for calibrating a data bus termination based on the calibration current,
wherein the reference calibration circuit includes a programmable resistance circuit and the reference calibration circuit is configured to program a resistance of the programmable resistance circuit using the reference current, and
wherein the calibration current is based on the resistance of the programmable resistance circuit.