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NSD-1102

Dual Piezo Motor Driver ASIC for SQL Series SQUIGGLE Motors

FEATURES DESCRIPTION

Wide Input Supply Voltage Range: 2.8 to 5.5VDC The NSD-1102 is a dedicated piezo motor driver ASIC capable of driving two SQL Series SQUIGGLE motors from a single 2.8 to 5.5 VDC supply. The two motors can be controlled independently using a standard I²C interface. An on-chip DC-DC step-up converter generates the high supply voltage (24 to 40 VDC) required by the piezoelectric elements of the SQUIGGLE motor. Four half bridge drivers create pairs of phase-shifted square waves with ultrasonic frequency as required to drive SQL Series SQUIGGLE motors. Step-up converter to generate programmable high-voltage power supply (24 to 40V) Minimum 70% efficiency (at VDD = 2.8V, Iout = 25mA, freq = 2Mz) 4x output driver with defined rise/fall time I²C interface On chip registers store driver instructions Power-down mode for minimal power consumption in stand-by Small 4x4mm 16-Pin QFN Package

APPLICATION

SQUIGGLE piezoelectric motor driver

SYSTEM BLOCK DIAGRAM

3.3µH The figure shows the main building blocks of the system: the voltage reference, step up converter, I²C interface, registers, selectable feedback, and four (4) half bridge drivers. Supplementary blocks such as biasing or power-on reset are not shown. The step-up converter is built as a hysteretic step-up converter. The half bridge drivers operate rail to rail (VSSP to VDDH). User supplied external components C1, C2, L1 and D1 provide voltage boost and regulation. The output voltage can be programmed via the I²C interface in 0.5V steps between 24V and 40V. This voltage determines the speed of the motor. Registers define the switching frequency of the motor, which can be dynamically adjusted from 140 KHz to 180 KHz for optimum motor performance. Other registers control motor direction and the number of pulses the motor is active (correlating to distance traveled). The XPD input enables a stand- by mode.
22µF NSD-1102 Functional Block Diagram New Scale Technologies, Inc. ~ www.newscaletech.com ~ Phone (585) 924-4450 1 of 9