Sanyo LB1924 Power brushless motor driver ic for office automation equipment Datasheet

Ordering number : ENN5687B
Monolithic Digital IC
LB1924
Power Brushless Motor Driver IC for Office
Automation Equipment
Overview
Package Dimension
The LB1924 is a direct PWM drive output driver IC
appropriate for the power brushless motors used in office
automation equipment. It includes a speed control circuit,
an FG amplifier, and other peripheral circuits and allows a
drive circuit to be implemented with a single IC. It allows
the number of external components to be reduced by
including a lock protection circuit, a kickback absorption
diode for the lower output side, and other components on
chip.
unit: mm
3147B-DIP28H
[LB1924]
0.4
R1.7
1
Functions
14
20.0
Breakdown voltage: 30 V, output current: 3.1 A
Direct PWM drive output
Speed discriminator + PLL speed control technique
Crystal oscillator circuit
Built-in FG and integrating amplifiers
Forward/reverse switching circuit
Speed lock detection output
On-chip lower output side kickback absorption diode
Full complement of built-in protection circuits,
including lock protection, current limiter, and thermal
protection circuits
4.0
27.0
4.0
•
•
•
•
•
•
•
•
•
15
12.7
11.2
8.4
28
1.93
1.78
0.6
1.0
SANYO: DIP28H
Any and all SANYO products described or contained herein do not have specifications that can handle
applications that require extremely high levels of reliability, such as life-support systems, aircraft’s
control systems, or other applications whose failure can be reasonably expected to result in serious
physical and/or material damage. Consult with your SANYO representative nearest you before using
any SANYO products described or contained herein in such applications.
SANYO assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other
parameters) listed in products specifications of any and all SANYO products described or contained
herein.
SANYO Electric Co.,Ltd. Semiconductor Company
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN
73099TH (OT)/83097HA(OT) No. 5687-1/11
LB1924
Specifications
Absolute Maximum Ratings at Ta = 25°C
Parameter
Maximum supply voltage
Output current
Allowable power dissipation
Symbol
Conditions
Ratings
VCC max
Unit
30
V
V
VM max
VCC ≥ VM
30
IO max
t ≤ 500 ms
3.1
A
3
W
Pd max1
Independent IC
Pd max2
With an arbitrarily large heat sink
20
W
Operating temperature
Topr
–20 to +80
°C
Storage temperature
Tstg
–55 to +150
°C
Allowable Operating Conditions at Ta = 25°C
Parameter
Supply voltage range
Regulated voltage output current
Lock detection output current
Symbol
Conditions
Ratings
Unit
9.5 to 28
VCC
VCC ≥ VM
V
9 to 28
V
IREG
0 to –20
mA
ILD
0 to 15
mA
VM
Electrical Characteristics at Ta = 25°C, VCC = VM = 24 V
Parameter
Current drain
Output saturated voltage
Output leakage current
Symbol
Conditions
Ratings
min
typ
ICC1
max
Unit
31
40
mA
When stopped
5.5
8.0
mA
VO sat1
IO = 1A, VO (Sink) + VO (Source)
2.0
2.5
V
VO sat2
IO = 2A, VO (Sink) + VO (Source)
2.6
3.2
V
100
µA
ICC2
IO leak
[5-V Regulated Voltage Output]
Output voltage
VREG
5.00
5.35
V
Line regulation
∆VREG1
IO = –5 mA
VCC = 9.5 to 28 V
4.65
30
100
mV
Load regulation
∆VREG2
IO = –5 to –20 mA
20
100
mV
[Hall Amplifier]
Input bias current
Common-mode input voltage range
IHB
–4
VICM
1.5
Hall input sensitivity
–1
µA
VREG–1.5
60
V
mVp-p
Hysteresis
∆VIN
Input voltage (low to high)
VSLH
7
mV
Input voltage (high to low)
VSHL
–7
mV
8
14
24
mV
[RC Oscillator]
Output high-level voltage
VOH(CR)
2.4
2.7
3.0
Output low-level voltage
VOL(CR)
1.1
1.4
1.7
R = 22 kΩ, C = 4700 pF
19
V
V
kHz
Oscillator frequency
f (CR)
Amplitude
V (CR)
1.0
1.25
1.5
Vp-p
Output high-level voltage
VOH(RK)
2.5
2.8
3.1
V
Output low-level voltage
VOL(RK)
0.5
0.8
1.1
V
ICHG1
–10
–8
–6
µA
8
10
µA
[CROCK Oscillator]
External capacitor charging current
ICHG2
6
C = 0.047 µF
44
Hz
Oscillator frequency
f (RK)
Amplitude
V(RK)
1.75
1.95
2.25
V
VCC-VM
0.45
0.5
0.55
V
150
180
°C
40
°C
[Current Limiter Operation]
Limiter
[Thermal Shutdown Operation]
Thermal shutdown temperature
Hysteresis
TSD
Design target value (junction temperature)
∆TSD
Design target value (junction temperature)
Continued on next page.
No. 5687-2/11
LB1924
Continued from preceding page.
Parameter
Symbol
Conditions
Ratings
min
typ
Unit
max
[FG Amplifier]
Input offset voltage
Input bias current
VIO(FG)
–10
+10
mV
IB(FG)
–1
+1
µA
Output high-level voltage
VOH(FG)
IFGO = –0.2 mA
Output low-level voltage
VOL(FG)
IFGO = 0.2 mA
FG input sensitivity
Gain times 100
Schmitt sensitivity for the next stage
Design target value
VREG–1.2
VREG–0.8
0.8
3
100
f (FG) = 2 kHz
V
mV
180
Operating frequency range
Open loop gain
V
1.2
45
51
VREG–1.0
VREG–0.7
250
mV
2
kHz
dB
[Speed Discriminator]
Output high-level voltage
VOH(D)
IDO = –0.1 mA
Output low-level voltage
VOL(D)
IDO = 0.1 mA
0.8
Number of counts
V
1.1
V
512
[PLL Output]
Output high-level voltage
VOH(P)
IPO = –0.1 mA
Output low-level voltage
VOL(P)
IPO = 0.1 mA
VOL(LD)
ILD = 10 mA
VREG–1.8
VREG–1.5
VREG–1.2
V
1.2
1.5
1.8
V
0.15
0.5
[Lock Detector]
Output low-level voltage
Lock range
6.25
V
%
[Integrator]
Input bias current
–0.4
IB(INT)
Output high-level voltage
VOH(INT)
IINTO = –0.2 mA
Output low-level voltage
VOL(INT)
IINTO = 0.2 mA
Open-loop gain
f (INT) = 1 kHz
Gain-bandwidth product
Design target value
Reference voltage
Design target value
VREG–1.2
+0.4
VREG–0.8
0.8
45
51
–5%
VREG/2
µA
V
1.2
V
dB
450
kHz
5%
V
10
MHz
[Crystal Oscillator]
Operating frequency range
1
fOSC
Low-level pin voltage
VOSCL
IOSC = –0.5 mA
1.7
V
High-level pin current
IOSCH
VOSC = VOSCL +0.3 V
0.5
mA
[Start/Stop Pin]
High-level input voltage range
VIH(S/S)
3.5
VREG
V
Low-level input voltage range
VIL(S/S)
0
1.5
V
Input open voltage
VIO(S/S)
VREG–0.5
VREG
V
Hysteresis
∆VIN
High-level input current
IIH(S/S)
V(S/S) = VREG
Low-level input current
IIL(S/S)
V(S/S) = 0 V
0.35
0.50
0.65
V
–10
0
+10
µA
–280
–210
µA
[Forward/Reverse Pin]
Output high-level voltage
VIH(F/R)
3.5
VREG
V
Output low-level voltage
VIL(F/R)
0
1.5
V
Input open voltage
VIO(F/R)
VREG–0.5
VREG
V
Hysteresis
∆VIN
Output high-level voltage
IIH(F/R)
V(F/R) = VREG
Output low-level voltage
IIL(F/R)
V(F/R) = 0 V
0.35
0.50
0.65
V
–10
0
+10
µA
–280
–210
µA
No. 5687-3/11
Allowable power dissipation, Pdmax – W
LB1924
With an arbitrarily large heat sink
Independent IC
Ambient temperature, Ta – °C
Pin Assignment
Truth Table
Source
F/R = L
Sink
F/R=H
IN 1
IN2
IN 3
IN 1
IN 2
IN 3
1
OUT2 → OUT1
H
L
H
L
H
L
2
OUT3 → OUT1
H
L
L
L
H
H
3
OUT3 → OUT2
H
H
L
L
L
H
4
OUT1 → OUT2
L
H
L
H
L
H
5
OUT1 → OUT3
L
H
H
H
L
L
6
OUT2 → OUT3
L
L
H
H
H
L
No. 5687-4/11
LB1924
Equivalent Circuit Block Diagram
No. 5687-5/11
LB1924
Functional Description
1. Speed control circuit
This IC uses a speed discriminator circuit and a PLL circuit in combination for speed control. The speed control
circuit outputs an error signal once every two FG periods (a charge pump technique). The PLL circuit outputs a phase
error signal once every FG period (also a charge pump technique). As compared with the earlier speed control
technique of using only a speed discriminator, the combined speed discriminator/PLL circuit technique is better able
to suppress speed fluctuations when used with motors with large load variations. The FG servo frequency is
determined by the following equation, which means that the motor speed is determined by the number of FG pulses
and the crystal oscillator frequency.
fFG(servo) = fOSC/8192
fOSC: Crystal oscillator frequency
2. Output drive circuit
This IC adopts a direct PWM drive technique to minimize the power loss in the output. The output transistor is
always saturated when on, and the motor drive power is adjusted by varying the duty with which the output is on.
Since the lower side output transistor is used for output switching, a Schottky diode or similar device must be
connected between OUT and VCC. (This is because a through current will flow at the instant the lower side transistor
turns on unless a diode with a short reverse recovery time is used.) The diode between OUT and ground is included
on chip in this device. If this becomes a problem for large output currents, (e.g. if the output waveform is disturbed
during lower side kickback) attach an external rectifying (or Schottky) diode.
3. Current limiter
The current limiter circuit limits the output to a current determined by the equation I = VRF/Rf, where VRF = 0.5 V
(typical) and Rf is the current detection resistor. The current limiting operation consists of reducing the output on duty
to lower the current.
4. Reference clock
Either of the two following input methods can be used for the speed control clock
• Using a crystal oscillator element
— When using a crystal oscillator element, connect the crystal, capacitors, and resistors as shown in the figure below
to form an oscillator circuit.
Sample External Circuit Constants (Reference values)
Oscillator frequency (MHz)
C1 (µF)
C2 (µF)
C3 (µF)
R1 (Ω)
R2 (Ω)
1 to 3
0.1
47
220
220 K
—
3 to 5
0.1
18
100
100 K
—
5 to 7
0.1
—
47
47 K
—
7 to 10
0.1
—
33
10 K
4.7 K
VREG
C1, R1:
C3:
C2:
R2:
Oscillator stabilization
Oscillator coupling
Overtone prevention
Oscillator operating margin improvement
This circuit and these circuit constant values are provided for reference only. Always verify application circuits
with the supplier of the oscillator element to assure that the effects of the characteristics of the oscillator element
itself, the printed circuit board wiring, floating capacitances, and other aspects are accounted for appropriately.
(Notes on printed circuit board lines)
Floating capacitances on the printed circuit board can easily affect crystal oscillator circuits, since these are highspeed circuits. The printed circuit board lines connecting these components should be kept as short and as narrow
as possible and other measures to reduce floating capacitances should be considered as well.
In this external circuit, the line between the oscillator element and C3 (C2) is particularly subject to floating
capacitance problems and requires special care.
No. 5687-6/11
LB1924
• External clock (A frequency equivalent to the crystal oscillator frequency: 1 to 10 MHz)
— If a frequency equivalent to a crystal oscillator frequency is input from an external source, input that signal through
a series resistor of about 13 kΩ to the XI pin. The XO pin should be left open.
Input signal levels:
Low-level voltage: 0 to 0.8 V
High-level voltage: 2.5 to 5.0 V
5. Speed lock range
The speed lock range is ±6.25% of the set speed. When the motor speed is in the lock range the LD pin will go low
(open collector output). The IC controls the motor speed by changing the motor drive output on duty according to the
speed error signal if the motor speed goes outside the lock range.
6. PWM frequency
The PWM frequency is determined by the capacitor and resistor connected to the CR pin.
fPWM ≈ 1/(0.5 × C × R)
A PWM frequency in the range 15 to 25 kHz is desirable. If the PWM frequency is too low, the motor may resonate
at the PWM frequency when locked resulting in noise, since that frequency will be in the audible range. If the PWM
frequency is too high, the switching loss in the output transistor will increase. The value of the resistor must be over 5
kΩ.
7. Hall input signals
The signals input as the Hall inputs must have amplitudes that exceed the hysteresis, which has a maximum value of
24 mV. Considering noise, inputs with amplitudes of at least 100 mV are desirable. Attach a noise rejection capacitor
(around 0.001 to 0.01 µF) across the IN3 Hall input (pins 26 and 27). Since these pins are adjacent to the OUT1
output pin, noise in this input may cause disturbances in the output waveforms.
8. F/R switching
The F/R pin can be used to change the direction of motor rotation. However the following points must be observed
when designing applications that will change the motor direction while the motor is turning.
• Application circuit must be designed to handle the through current that occurs when the direction is switched.
However, increases in the VCC voltage during switching due to motor current flowing into the power supply system
instantaneously, must not exceed the rated voltage (30 V) of the device. Increase the value of the capacitor between
power supply and ground if this is a problem.
• If the motor current after switching exceeds the current limiter upper limit, the lower side transistor will be turned
off. However, the high side transistor will go to the short braking state, and a current determined by the motor reverse
voltage and the coil resistance will flow in this transistor. Applications must be designed so that this current does not
exceed the rated current, 3.1 A. In general, switching the direction with the F/R pin at high motor speeds is
dangerous.
9. Lock protection circuit
This IC includes a built-in lock protection circuit to protect the IC and the motor when the motor is locked. In the
start state, if the LD output remains high for a fixed period (the unlocked state), the lower side transistor is turned off.
The capacitance of the capacitor connected to the CROCK pin sets this time. A time of a few seconds can be set with
a capacitance under 0.1 µF.
Set time (seconds) ≈ 52 × C (µF)
To release the lock protection state, the IC must be set to the stopped state or the power must be turned off and
reapplied. The CROCK pin must be connected to ground if the lock protection circuit is not used.
10. Power supply stabilization
The large currents drawn by this IC can adversely affect the power supply voltage. Therefore a capacitor with a
sufficiently large value must be inserted between the VCC pin and ground. If a diode is inserted in the power supply
line to protect against destruction due to accidentally connecting the power supply with the polarity reversed, the
power supply line voltage will be even more easily affected and an even larger capacitor will be required.
No. 5687-7/11
LB1924
Pin Functions
Pin No.
Pin
28
1
2
OUT1
OUT2
OUT3
Pin function
3
GND2
5
VM
Output block power supply and output current detection.
Connect a resistor (Rf) with a small resistance between this
pin and VCC.
The output current is limited to a current set according to the
equation IOUT = VRF/Rf.
4
VCC
Power supply (blocks other than the output block)
6
VREG
Regulated power supply output (5-V output)
Insert a capacitor (about 0.1 µF) between this pin and ground
for regulation.
7
F/R
Forward/reverse control
Low: 0 to 1.5 V
High: 3.5 to VREG
The open state functions as a high-level input.
Has a hysteresis of about 0.5 V.
Low: Forward
High or open: Reverse
8
S/S
Start/stop control
Low: 0 to 1.5 V
High: 3.5 to VREG
The open state functions as a high-level input.
Has a hysteresis of about 0.5 V.
Low: Start
High or open: Stop
Equivalent circuit
Motor drive outputs
Connect Schottky diodes between these outputs and VCC.
Output block ground
Continued on next page.
No. 5687-8/11
LB1924
Continued from preceding page.
Pin No.
Pin
9
10
XO
XI
11
INTOUT
Pin function
Equivalent circuit
Crystal oscillator connection.
The reference clock signal is generated by connecting a
crystal oscillator element to these pins.
If an external clock (with a frequency of a few MHz) is used,
connect that signal to the XI pin through a series resistor of
about 13 kΩ, and leave the XO pin open.
Integrator amplifier output (speed control output)
PWM comparator
12
INTIN
Integrator amplifier input
13
POUT
PLL circuit output
Continued on next page.
No. 5687-9/11
LB1924
Continued from preceding page.
Pin No.
Pin
14
DOUT
15
LD
16
FGOUT
Pin function
Equivalent circuit
Speed discriminator output.
High: Acceleration
Low: Deceleration
Speed lock detection output
Outputs a low level when the motor speed is in the lock range
(±6.25%).
FG amplifier output
FG Schmitt comparator
17
FGIN–
FG amplifier input
FG reset circuit
18
FGIN+
FG amplifier input (bias input).
The logic block initial reset is applied by connecting a
capacitor (of about 0.1 µF) between FGIN+ and ground.
19
CROCK
Setting for the lock protection circuit operating time.
An operating time of about 2.5 seconds can be set by
connecting a capacitor of about 0.047 µF between the
CROCK pin and ground.
Continued on next page.
No. 5687-10/11
LB1924
Continued from preceding page.
Pin No.
Pin
20
CR
Pin function
21
GND1
22
23
24
25
26
27
IN1+
IN1–
IN2+
IN2–
IN3+
IN3–
Equivalent circuit
PWM oscillator frequency setting.
Connect a resistor (R) between this pin and V REG and a
capacitor (C) between this pin and ground. Values of R = 22
kΩ, and C = 4700 pF set a frequency of about 19 kHz.
Ground (blocks other than the output block)
Hall inputs
An input with IN+ > IN– is taken to be a high level, and the
opposite state is taken to be a low level. Hall signals with
amplitudes greater that 100 mVp-p (differential) are desirable.
If noise on the Hall signals is a problem, connect capacitors
between the IN+ and IN– pins.
Specifications of any and all SANYO products described or contained herein stipulate the performance,
characteristics, and functions of the described products in the independent state, and are not guarantees
of the performance, characteristics, and functions of the described products as mounted in the customer’s
products or equipment. To verify symptoms and states that cannot be evaluated in an independent device,
the customer should always evaluate and test devices mounted in the customer’s products or equipment.
SANYO Electric Co., Ltd. strives to supply high-quality high-reliability products. However, any and all
semiconductor products fail with some probability. It is possible that these probabilistic failures could
give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire,
or that could cause damage to other property. When designing equipment, adopt safety measures so
that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective
circuits and error prevention circuits for safe design, redundant design, and structural design.
In the event that any or all SANYO products (including technical data, services) described or contained
herein are controlled under any of applicable local export control laws and regulations, such products must
not be exported without obtaining the export license from the authorities concerned in accordance with the
above law.
No part of this publication may be reproduced or transmitted in any form or by any means, electronic or
mechanical, including photocopying and recording, or any information storage or retrieval system,
or otherwise, without the prior written permission of SANYO Electric Co., Ltd.
Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the “Delivery Specification”
for the SANYO product that you intend to use.
Information (including circuit diagrams and circuit parameters) herein is for example only; it is not
guaranteed for volume production. SANYO believes information herein is accurate and reliable, but
no guarantees are made or implied regarding its use or any infringements of intellectual property rights
or other rights of third parties.
This catalog provides information as of July, 1999. Specifications and information herein are subject to
change without notice.
PS No. 5687-11/11