1FEATURES
• QML-V Qualified, SMD 5962-89957
• Rad Tolerant: 30 kRad(Si) TID (1)
– TID Dose Rate = 10 mRad/sec
• Single or Dual Supply Operation
• ±2.5-V to ±20-V Input Supply Range
• ±5% Initial Oscillator Accuracy; ±10% Over
Temperature
• Pulse-by-Pulse Current Limiting
• Under-Voltage Lockout
• Shutdown Input with Temperature
Compensated 2.5-V Threshold
• Uncommitted PWM Comparators for Design

DESCRIPTION
The UC1637 is a pulse width modulator circuit intended to be used for a variety of PWM motor drive and
amplifier applications requiring either uni-directional or bi-directional drive circuits. When used to replace
conventional drivers, this circuit can increase efficiency and reduce component costs for many applications. All
necessary circuitry is included to generate an analog error signal and modulate two bi-directional pulse train
outputs in proportion to the error signal magnitude and polarity.
This monolithic device contains a sawtooth oscillator, error amplifier, and two PWM comparators with ±100-mA
output stages as standard features. Protection circuitry includes under-voltage lockout, pulse-by-pulse current
limiting, and a shutdown port with a 2.5-V temperature compensated threshold.
The UC1637 is characterized for operation over the full space temperature range of –55°C to 125°C.