TEA3717DP STMicroelectronics, TEA3717DP Datasheet - Page 4

• Manufacturer Part Number: TEA3717DP
• Description: IC DRIVER STEP MOTOR 16 POWERDIP
• Manufacturer: STMicroelectronics
• Type: Driverr

Specifications of TEA3717DP

• Applications: Stepper Motor Driver
• Number Of Outputs: 1
• Current - Output: ± 1A
• Voltage - Load: 10 V ~ 40 V
• Voltage - Supply: 4.75 V ~ 5.25 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 16-DIP (0.300", 7.62mm)
• Product: Stepper Motor Controllers / Drivers
• Operating Supply Voltage: 4.75 V to 5.25 V
• Supply Current: 0.8 A
• Mounting Style: Through Hole
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-2187-5

TEA3717
FUNCTIONAL DESCRIPTION
The circuit is intented to drive a bipolar constant cur-
rent through one motor winding. The constant cur-
rent is generated through switch mode regulation.
There is a choice of three different current levels with
the two logic inputs l
be switched off completely.
INPUT LOGIC
If any of the logic inputs is left open, the circuit will
treat it as a high level input.
PHASE This input determines the direction of cur-
rent flow in the winding, depending on the motor
connections. The signal is fed through a Schmidt-
trigger for noise immunity, and through a time delay
in order to guarantee that no short-circuit occurs in
the output stage during phase-shift. High level on
the PHASE-input causes the motor current flow
from M
l
selected with these inputs. The values of the differ-
ent current levels are determined by the reference
voltage V
sistor R
CURRENT SENSOR
This part contains a current sensing resistor (R
low pass filter (R
one comparator is active at a time. It is activated by
the input logic according to the current level chosen
with signals l
through the sensing resistor R
has increased so that the voltage across R
comes higher than the reference voltage on the
Note : R
4/8
0
and l
I
H
H
L
L
0
R
C
R
S
C
C
t
A
1
S
= 1 , inductance free
= 1 k
= 820 pF, ceramic
= 56 k
through the winding to M
.
R
The current level in the motor winding is
together with the value of the sensing re-
I
H
H
L
L
1
0
C
and l
, C
No Current
Low Current
Medium Current
Maximum Current
C
0
) and three comparators. Only
1
and l
. The motor current flows
Current Level
1
. The current can also
S
. When the current
B
.
S
S
be-
), a
other comparator input, the comparator output goes
high, which triggers the pulse generator and its out-
put goes high during a fixed pulse time (t
switching off the power feed to the motor winding,
and causing the motor current to decrease during
t
SINGLE-PULSE GENERATOR
The pulse generator is a monostable triggered on
the positive going edge of the comparator output.
The monostable output is high during the pulse time,
t
R
The single pulse switches off the power feed to the
motor winding, causing the winding current to de-
crease during t
If a new trigger signal should occur during t
ignored.
OUTPUT STAGE
The output stage contains four Darlington transis-
tors and four diodes, connected in an H-bridge. The
two sinking transistors are used to switch the pow-
ersupplied to the motor winding, thus driving a con-
stant current through the winding.
It should be noted however, that it is not permitted
to short circuit the outputs.
V
The circuit will stand any order of turn-on or turn-off
of the supply voltages V
values are then assumed.
Preferably, V
on and power-off.
ANALOG CONTROL
The current levels can be varied continuously either
if V
into the comparator terminal (see fig.1).
off.
off
CC
t
, which is determined by the timing components
and C
R
, V
is varied or with a circuit varying the voltage fed
mm
t
.
, V
R
R
should be tracking V
off
t
off
.
= 0.69 R
SS
and V
t
C
t
CC
S
. Normal dV/dt
during power-
off
off
), thus
, it is