ThePBL3717Ais amonolithic ICwhich controlsand
drives one phase of a bipolar stepper motor with
choppercontrolof the phase current. Current levels
maybeselected in threestepsbymeans of two logic
inputs which select one of three current comparators.
When both of these inputs are high the device
is disabled.A separatelogic input controls the direction
of current flow.
A monostable,programmed by an externalRC network,
sets the current decay time.
The power section is a full H-bridge driver with four
internal clamp diodes for current recirculation. An
externalconnectionto theloweremitters isavailable
for the insertion of a sensing resistor. Two
PBL3717As and few external components form a
complete stepper motor drive subsystem.
The raccomended operating ambient temperature
ranges is from 0 to 70 °C.
The PBL3717Ais supplied in a 12 + 2 + 2 lead Powerdip
package.