General Description
The LM621 is a bipolar IC designed for commutation of
brushless DC motors. The part is compatible with both
three- and four-phase motors. It can directly drive the POWER
switching devices used to drive the motor. The LM621 provides
an adjustable dead-time circuit to eliminate ``shootthrough''
current spiking in the POWER switching circuitry.
Operation is from a 5V supply, but output swings of up to
40V are accommodated. The part is packaged in an 18-pin,
dual-in-line package.
FEATURES
Unique 1-Wire interface requires only one port pin for communication
Multidrop capability simplifies distributed temperature sensing applications
Requires no external components
Can be POWERed from data line. POWER supply range is 3.0V to 5.5V
Zero standby POWER required
Measures temperatures from -55°C to +125°C. Fahrenheit equivalent is -67°F to +257°F
±0.5°C accuracy from -10°C to +85°C
Thermometer resolution is programmable from 9 to 12 bits
Converts 12-bit temperature to digital word in 750 ms (max.)
User-definable, nonvolatile temperature alarm settings
Alarm search command identifies and addresses devices whose temperature is outside of programmed limits (temperature
alarm condition)
Applications include thermostatic controls, industrial systems, consumer products,
thermometers, or any thermally sensitive system