PBL3717A Datasheet, PDF (2/11 Pages) STMicroelectronics – STEPPER MOTOR DRIVER

PBL3717A
PIN FUNCTIONS
N°
Name
Function
1
UTPUT B
Output Connection (with pin 15). The output stage is a ”H” bridge formed by four
transistors and four diodes suitable for switching applications.
2
PULSE TIME
A parallel RC network connected to this pin sets the OFF time of the lower power
transistors. The pulse generator is a monostable triggered by the rising edge of
the output of the comparators (t_off = 0.69 R_T C_T).
3 SUPPLY VOLTAGE B Supply Voltage Input for Half Output Stage
See also pin 14.
4
GROUND
Ground Connection. With pins 5, 12 and 13 also conducts heat from die to
printed circuit copper.
5
GROUND
See pin 4.
6
LOGIC SUPPLY Supply Voltage Input for Logic Circuitry
7
INPUT 1
This pin and pin 9 (INPUT 0) are logic inputs which select the outputs of the
three comparators to set the current level. Current also depends on the sensing
resistor and reference voltage. See truth table.
8
PHASE
This TTL-compatible logic input sets the direction of current flow through the
load. A high level causes current to flow from OUTPUT A (source) to OUTPUT
B (sink). A schmitt trigger on this input provides good noise immunity and a delay
circuit prevents output stage short circuits during switching.
9
INPUT 0
See INPUT 1 (pin 7) .
10
COMPARATOR
Input connected to the three comparators. The voltage across the sense resistor
INPUT
is feedback to this input through the low pass filter RC CC. The lower power
transistor are disabled when the sense voltage exceeds the reference voltage of
the selected comparator. When this occurs the current decays for a time set by
R_T C_T, t_off = 0.69 R_T C_T.
11
REFERENCE
A voltage applied to this pin sets the reference voltage of the three comparators,
this determining the output current (also thus depending on Rs and the two inputs
INPUT 0 and INPUT 1).
12
GROUND
See pin 4.
13
GROUND
See pin 4.
14 SUPPLY VOLTAGE A Supply Voltage Input for Half Output Stage. See also pin 13.
15
OUTPUT A
See pin 1.
16
SENSE RESISTOR Connection to Lower Emitters of Output Stage for Insertion of Current Sense
Resistor
TRUTH TABLE
Inpu t 0 (pin 9)
H
L
H
L
Input 1 (pin 7)
H
H
L
L
No Current
Low Current
Medium Current
High Current
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