Overview
The LB1846M and LB1848M are 2-channel low-voltage,
low saturation voltage type bidirectional motor driver ICs
that are optimal for use as 2-phase stepping motor drivers
in printers, floppy disk drives, and cameras and other
portable equipment. The output circuits are of the bipolar
type, with pnp transistors in the upper side and npn
transistors in the lower side, and they achieve low
saturation output and low power characteristics despite
being provided in a miniature package.
Both of these IC products can directly control a motor
from signals from a microcontroller. The LB1846M is
optimal for 1-2 phase excitation drive for 2-phase stepping
motors using 4-input logic (IN1, IN2, IN3, and IN4) and
the LB1848M is optimal for 2-phase excitation drive for
2-phase stepping motors using 3-input logic (ENA, IN1,
and IN2).
Another point is that these ICs include built-in thermal
shutdown circuits so that IC scorching or burning is
prevented in advance even if the IC outputs are shorted.
Additionally, the MFP-10S miniature package used
supports reduced-space mounting.
Features
Optimal for 1-2 phase excitation drive for 2-phase
stepping motors (LB1846M)
Optimal for 2 phase excitation drive for 2-phase
stepping motors (LB1848M)
Low saturation voltage. V
O
(sat) = 0.55 V typical at I
O
=
400 mA
Standby current: zero
Thermal shutdown circuit
Miniature package: MFP-10S (6.5
5.1 mm)
Through-current prevention circuit (LB1848M only)
"Soft off" function that reduces power supply line noise
when switching from drive to standby modes. (Requires
the use of one external capacitor.) (LB1848M only)
No limitations on the magnitude relationship between
the power supply voltage (V
CC
) and the input voltage
(V
IN
)
Package Dimensions
unit: mm
3086A-MFP10S
Monolithic Digital IC
Ordering number : EN5339
O3096HA (OT) No. 5339-1/6
SANYO: MFP10S
[LB1846M, 1848M]
SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN
Low-Voltage/Low Saturation Voltage Type
Bidirectional Motor Driver
LB1846M, 1848M
No. 5339-2/6
LB1846M, 1848M
Parameter
Symbol
Conditions
Ratings
Unit
Supply voltage
V
CC
2.5 to 7.5
V
Input high-level voltage
V
IH
2.0 to 7.5
V
Input low-level voltage
V
IL
0.3 to +0.7
V
Allowable Operating Ranges
at Ta = 25C
Parameter
Symbol
Conditions
Ratings
Unit
min
typ
max
[LB1846M]
Current drain
I
CC
0
IN1, 2, 3, 4 = 0 V
0.1
10
A
I
CC
1
IN1, 3 = 3 V, IN2, 4 = 0 V
30
40
mA
V
OUT
1
V
IN
= 3 V or 0 V, V
CC
= 3 to 7.5 V,
0.27
0.4
V
Output saturation voltage
I
OUT
= 200 mA
V
OUT
2
V
IN
= 3 V or 0 V, V
CC
= 4 to 7.5 V,
0.55
0.8
V
I
OUT
= 400 mA
Input current
I
IN
V
IN
= 5 V
150
200
A
[Spark Killer Diode]
Reverse current
I
S
(leak)
30
A
Forward voltage
V
SF
I
OUT
= 400 mA
1.7
V
[LB1848M]
Current drain
I
CC
0
ENA = 0 V, V
IN
= 3 V or 0 V
0.1
10
A
I
CC
1
ENA = 3 V, V
IN
= 3 V or 0 V
25
35
mA
V
OUT
1
ENA = 3 V, V
IN
= 3 V or 0 V,
0.27
0.4
V
Output saturation voltage
V
CC
= 3 to 7.5 V, I
OUT
= 200 mA
V
OUT
2
ENA = 3 V, V
IN
= 3 V or 0 V,
0.55
0.8
V
V
CC
= 4 to 7.5 V, I
OUT
= 400 mA
Input current 1
I
IN
V
IN
= 5 V
75
100
A
Input current 2
I
ENA
ENA = 5 V
85
110
A
[Spark Killer Diode]
Reverse current
I
S
(leak)
30
A
Forward voltage
V
SF
I
OUT
= 400 mA
1.7
V
Electrical Characteristics
at Ta = 25C, V
CC
= 5.0 V
Pin Assignments
Parameter
Symbol
Conditions
Ratings
Unit
Maximum supply voltage
V
CC
max
0.3 to +8.0
V
Output voltage
V
OUT
V
CC
+ V
SF
V
Input voltage
V
IN
0.3 to +8.0
V
Ground pin outflow current
I
GND
Per channel
800
mA
Allowable power dissipation
Pd max1
Independent IC
350
mW
Pd max2
When mounted
*
870
mW
Operating temperature
Topr
20 to +75
C
Storage temperature
Tstg
40 to +150
C
Specifications
Absolute Maximum Ratings
at Ta = 25C
Note:
*
On the specified circuit board (a 114.3
76.2
1.5-mm glass-epoxy printed circuit board)
Note: The thermal shutdown circuit function values are design guarantees, and are not tested.
Block Diagrams
[LB1846M]
[LB1848M]
Note: When the "soft off" function is used, a capacitor must be connected to the SOF pin. If this function is not used, this pin must be left open with absolutely
no signals or lines connected.
Notes on Wiring and Lines
Since large currents flow in the V
CC
and ground lines, oscillations may occur on these lines. The following points
should be observed if such oscillations occur.
(1) Lower the line impedances by making them shorter and thicker.
(2) Attach capacitors close to the IC.
(3) If the controller (CPU) is mounted on a separate printed circuit board, insert series resistors (of about 10 k
)
between the controller outputs and this IC.
No. 5339-3/6
LB1846M, 1848M
Truth Tables
[LB1846M]
Note: 1. "--" indicates a "don't care" input.
2. If two high levels (H/H) are input to the IN1/IN2 pins with the timing shown in
x
in the figure below, then the IN2 input that arrived later will be
ignored and the IC will function as though an H/L combination is applied to the IN1/IN2 pins. Similarly, the timing shown in
results in a L/H
combination on the IN1/IN2 pins.
No. 5339-4/6
LB1846M, 1848M
IN1
IN2
IN3
IN4
OUT1
OUT2
OUT3
OUT4
Notes
L
L
L
L
OFF
OFF
OFF
OFF
Standby
H
L
L
L
H
L
OFF
OFF
H
L
H
L
H
L
H
L
L
L
H
L
OFF
OFF
H
L
L
H
H
L
L
H
H
L
1-2 phase excitation
L
H
L
L
L
H
OFF
OFF
L
H
L
H
L
H
L
H
L
L
L
H
OFF
OFF
L
H
H
L
L
H
H
L
L
H
H
H
--
--
The logic output for the first high-level
--
--
H
H
input is produced.
*
2
[LB1848M]
Note: "--" indicates a "don't care" input.
ENA
IN1
IN2
OUT1
OUT2
OUT3
OUT4
Notes
L
--
--
OFF
OFF
OFF
OFF
Standby
L
L
H
L
H
L
H
L
H
H
L
L
H
2-phase excitation
H
H
L
H
L
H
H
L
L
H
H
L
SOF Pin ("Soft Off" Function) Operation [LB1848M only]
The soft off function reduces power supply line noise due to the kickback current generated when the stepping motor
drive mode is switched from drive to standby. The "soft off" function provided by this IC operates when a capacitor
(0.001 to 0.01 F) is connected between the SOF pin and ground. (Leave the SOF pin open to disable the soft off
function.)
The waveforms for each pin are shown below.
Timing Chart for Stepping Motor 2-Phase Excitation
No. 5339-5/6
LB1846M, 1848M
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