Title :
An accurate low-voltage analog memory-cell with built-in multiplication
Author :
De Lima, Jader A. ; Cordeiro, Adriano S.
Author_Institution :
Dept. of Electr. Eng., Univ. Estadual Paulista, Sao Paulo, Brazil
Abstract :
A CMOS memory-cell for dynamic storage of analog data and suitable for LVLP applications is proposed. Information is memorized as the gate-voltage of input-transistor of a gain-boosting triode-transconductor. The enhanced output-resistance improves accuracy on reading out the sampled currents. Additionally, a four-quadrant multiplication between the input to regulation-amplifier of the transconductor and the stored voltage is provided. Designing complies with a low-voltage 1.2 μm N-well CMOS fabrication process. For a 1.3 V-supply, CCELL=3.6 pF and sampling interval is 0.25 μA⩽ISAMPLE⩽0.75 μA. The specified retention time is 1.28 ms and corresponds to a charge-variation of 1% due to junction leakage @75°C. A range of PSPICE simulations confirm circuit performance. Absolute read-out error is below 0.40% while the four-quadrant multiplier nonlinearity at full-scale is 8.2%. Maximum stand-by consumption is 3.6 μW/cell
Keywords :
CMOS analogue integrated circuits; SPICE; analogue multipliers; analogue storage; circuit simulation; leakage currents; low-power electronics; 1.2 micron; 1.28 ms; 1.3 V; 3.6 pF; 75 degC; LVLP applications; N-well CMOS fabrication process; PSPICE simulations; absolute read-out error; analog memory-cell; built-in multiplication; charge-variation; circuit performance; four-quadrant multiplication; four-quadrant multiplier nonlinearity; gain-boosting triode-transconductor; gate-voltage; input to regulation-amplifier; junction leakage; low-voltage electronics; retention time; sampling interval; stand-by consumption; Boosting; CMOS process; Circuit simulation; Fabrication; Neural networks; SPICE; Sampling methods; Switches; Transconductors; Voltage;
Conference_Titel :
Circuits and Systems, 2001. ISCAS 2001. The 2001 IEEE International Symposium on
Conference_Location :
Sydney, NSW
Print_ISBN :
0-7803-6685-9
DOI :
10.1109/ISCAS.2001.921798
