A3967 Datasheet

A3967
Microstepping Driver with Translator
Features and Benefits
Description
▪ ±750 mA, 30 V output rating
▪ Satlington® sink drivers
▪ Automatic current-decay mode detection/selection
▪ 3.0 to 5.5 V logic supply voltage range
▪ Mixed, fast, and slow current-decay modes
▪ Internal UVLO and thermal shutdown circuitry
▪ Crossover-current protection
The A3967 is a complete microstepping motor driver with builtin translator. It is designed to operate bipolar stepper motors in
full-, half-, quarter-, and eighth-step modes, with output drive
capability of 30 V and ±750 mA. The A3967 includes a fixed
off-time current regulator that has the ability to operate in slow,
fast, or mixed current-decay modes. This current-decay control
scheme results in reduced audible motor noise, increased step
accuracy, and reduced power dissipation.
The translator is the key to the easy implementation of the
A3967. By simply inputting one pulse on the STEP input the
motor will take one step (full, half, quarter, or eighth depending
on two logic inputs). There are no phase-sequence tables, highfrequency control lines, or complex interfaces to program. The
A3967 interface is an ideal fit for applications where a complex
μP is unavailable or over-burdened.
Package: 24-pin SOIC with internally
fused pins (suffix LB)
Internal circuit protection includes thermal shutdown with
hysteresis, under-voltage lockout (UVLO) and crossovercurrent protection. Special power-up sequencing is not
required.
The A3967 is supplied in a 24-pin SOIC, which is lead (Pb)
free with 100% matte tin leadframe plating. Four pins are
fused internally for enhanced thermal dissipation. The pins
are at ground potential and need no insulation.
Not to scale
Functional Block Diagram
LOGIC
SUPPLY
VCC
LOAD
SUPPLY
UVLO
AND
FAULT
DETECT
14
REF.
SUPPLY
REF
VBB1
20
1
÷8
DAC
SENSE
+
-
RC1
OUT1A
PWM LATCH
BLANKING
MIXED DECAY
23
16
OUT1B
21
PWM TIMER
3
STEP 10
MS2 13
SLEEP
17
CONTROL LOGIC
MS1 12
SENSE1
TRANSLATOR
DIR 11
RESET 22
3
5
ENABLE 15
VPF
OUT2A
24
PFD
VBB2
9
PWM TIMER
3
OUT2B
4
PWM LATCH
BLANKING
MIXED DECAY
2
RC2
+
-
DAC
8
6
26184.24H
7
18 19
SENSE2
Dwg. FP-050-3A
A3967
Microstepping Driver with Translator
Selection Guide
Part Number
A3967SLBTR-T
Packing
Package
24-pin SOIC with internally fused pins
1000 per reel
Absolute Maximum Ratings
Characteristic
Symbol
Notes
Rating
Units
Load Supply Voltage
VBB
30
V
Logic Supply Voltage
VCC
7.0
V
Logic Input Voltage Range
VIN
tw > 30 ns
–0.3 to 7.0
V
tw < 30 ns
–1 to 7.0
V
VSENSE
0.68
V
Reference Voltage
Sense Voltage
VREF
VCC
mA
Continuous
±750
mA
Output Current
IOUT
Peak
±850
mA
–
–
–20 to 85
ºC
150
ºC
–55 to 150
ºC
Value
Units
50
ºC/W
35
ºC/W
Output current rating may be limited by duty cycle, ambient temperature, and heat sinking. Under any set of
conditions, do not exceed the specified current rating
or a junction temperature of 150°C.
Package Power Dissipation
PD
See graph
Operating Ambient Temperature
TA
Range S
Maximum Junction Temperature
Fault conditions that produce excessive junction temperature will activate
the device’s thermal shutdown circuitry. These conditions can be tolerated but should be avoided.
TJ(max)
Storage Temperature
Tstg
Thermal Characteristics
Characteristic
Symbol
Package Thermal Resistance, Junction
to Ambient
RθJA
Test Conditions*
2-layer PCB, 1.3
in.2
2-oz. exposed copper
4-layer PCB, based on JEDEC standard
ALLOWABLE PACKAGE POWER DISSIPATION (W)
*Additional thermal information available on Allegro website.
5
RQJT = 6.0oC/W
4
3
R QJA = 35°C/W
2
R QJA = 50°C/W
1
0
25
50
75
100
TEMPERATURE IN oC
125
150
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
A3967
Microstepping Driver with Translator
ELECTRICAL CHARACTERISTICS at TA = +25°C, VBB = 30 V, VCC = 3.0 V to 5.5V (unless otherwise
noted)
Limits
Characteristic
Symbol Test Conditions
Min.
Typ.
Max.
Units
4.75
–
30
V
During sleep mode
0
–
30
V
VOUT = VBB
–
<1.0
20
μA
VOUT = 0 V
–
<-1.0
-20
μA
Source driver, IOUT = -750 mA
–
1.9
2.1
V
Source driver, IOUT = -400 mA
–
1.7
2.0
V
Sink driver, IOUT = 750 mA
–
0.65
1.3
V
Sink driver, IOUT = 400 mA
–
0.21
0.5
V
IF = 750 mA
–
1.4
1.6
V
IF = 400 mA
–
1.1
1.4
V
Outputs enabled
–
–
5.0
mA
RESET high
–
–
200
μA
Sleep mode
–
–
20
μA
3.0
5.0
5.5
V
Output Drivers
Load Supply Voltage Range
VBB
Output Leakage Current
ICEX
Output Saturation Voltage
VCE(sat)
Clamp Diode Forward Voltage
Motor Supply Current
VF
IBB
Operating
Control Logic
Logic Supply Voltage Range
VCC
Logic Input Voltage
VIN(1)
0.7VCC
–
–
V
VIN(0)
–
–
0.3VCC
V
Logic Input Current
Operating
IIN(1)
VIN = 0.7VCC
-20
<1.0
20
μA
IIN(0)
VIN = 0.3VCC
-20
<1.0
20
μA
500*
–
–
kHz
1200
ns
Maximum STEP Frequency
fSTEP
Blank Time
tBLANK
Rt = 56 kΩ, Ct = 680 pF
700
950
toff
Rt = 56 kΩ, Ct = 680 pF
30
38
Fixed Off Time
46
μs
continued next page …
Table 1. Microstep Resolution Truth Table
MS1
MS2
Resolution
L
L
Full step (2 phase)
H
L
Half step
L
H
Quarter step
H
H
Eighth step
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
A3967
Microstepping Driver with Translator
ELECTRICAL CHARACTERISTICS (continued) at TA = +25°C, VBB = 30 V, VCC = 3.0 V to 5.5V (unless
otherwise noted)
Limits
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
PFDH
–
0.6VCC
–
V
PFDL
–
0.21VCC
–
V
1.0
–
VCC
V
Control Logic (cont’d)
Mixed Decay Trip Point
Ref. Input Voltage Range
VREF
Reference Input Impedance
ZREF
Gain (Gm) Error
EG
(note 3)
Thermal Shutdown Temp.
Thermal Shutdown Hysteresis
UVLO Enable Threshold
UVLO Hysteresis
Logic Supply Current
Operating
120
160
200
kΩ
VREF = 2 V, Phase Current = 38.37% †
–
–
±10
%
VREF = 2 V, Phase Current = 70.71% †
–
–
±5.0
%
VREF = 2 V, Phase Current = 100.00% †
–
–
±5.0
%
TJ
–
165
–
°C
∆TJ
–
15
–
°C
2.45
2.7
2.95
V
VUVLO
Increasing VCC
∆VUVLO
ICC
0.05
0.10
–
V
Outputs enabled
–
50
65
mA
Outputs off
–
–
9.0
mA
Sleep mode
–
–
20
μA
* Operation at a step frequency greater than the specified minimum value is possible but not warranteed.
† 8 microstep/step operation.
NOTES: 1. Typical Data is for design information only.
2. Negative current is defined as coming out of (sourcing) the specified device terminal.
3. EG = ([VREF/8] – VSENSE)/(VREF/8)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
A3967
Microstepping Driver with Translator
Functional Description
Device Operation. The A3967 is a complete microstepping motor driver with built in translator for easy operation
with minimal control lines. It is designed to operate bipolar
stepper motors in full-, half-, quarter- and eighth-step
modes. The current in each of the two output full bridges
is regulated with fixed off time pulse-width modulated
(PWM) control circuitry. The full-bridge current at each
step is set by the value of an external current sense resistor (RS), a reference voltage (VREF), and the DACs output
voltage controlled by the output of the translator.
At power up, or reset, the translator sets the DACs and
phase current polarity to initial home state (see figures for
home-state conditions), and sets the current regulator for
both phases to mixed-decay mode. When a step command
signal occurs on the STEP input the translator automatically sequences the DACs to the next level (see table 2 for
the current level sequence and current polarity). The microstep resolution is set by inputs MS1 and MS2 as shown in
table 1. If the new DAC output level is lower than the previous level the decay mode for that full bridge will be set
by the PFD input (fast, slow or mixed decay). If the new
DAC level is higher or equal to the previous level then the
decay mode for that Full bridge will be slow decay. This
automatic current-decay selection will improve microstepping performance by reducing the distortion of the current
waveform due to the motor BEMF.
Reset Input (RESET). The RESET input (active low)
sets the translator to a predefined home state (see figures
for home state conditions) and turns off all of the outputs.
STEP inputs are ignored until the RESET input goes high.
Step Input (STEP). A low-to-high transition on the
STEP input sequences the translator and advances the
motor one increment. The translator controls the input to
the DACs and the direction of current flow in each winding. The size of the increment is determined by the state of
inputs MS1 and MS2 (see table 1).
Microstep Select (MS1 and MS2). Input terminals
MS1 and MS2 select the microstepping format per
table 1. Changes to these inputs do not take effect until the
STEP command (see figure).
Direction Input (DIR). The state of the DIRECTION
input will determine the direction of rotation of the motor.
Internal PWM Current Control. Each full bridge is
controlled by a fixed off-time PWM current-control circuit that limits the load current to a desired value (ITRIP).
Initially, a diagonal pair of source and sink outputs are
enabled and current flows through the motor winding and
RS. When the voltage across the current-sense resistor
equals the DAC output voltage, the current-sense comparator resets the PWM latch, which turns off the source driver
(slow-decay mode) or the sink and source drivers (fast- or
mixed-decay modes).
The maximum value of current limiting is set by the
selection of RS and the voltage at the VREF input with a
transconductance function approximated by:
ITRIPmax = VREF/8RS
The DAC output reduces the VREF output to the current-sense comparator in precise steps (see table 2 for %
ITRIPmax at each step).
ITRIP = (% ITRIPmax/100) x ITRIPmax
Fixed Off-Time. The internal PWM current-control
circuitry uses a one shot to control the time the driver(s)
remain(s) off. The one shot off-time, toff, is determined by
the selection of an external resistor (RT) and capacitor (CT)
connected from the RC timing terminal to ground. The off
time, over a range of values of CT = 470 pF to 1500 pF and
RT = 12 kΩ to 100 kΩ is approximated by:
toff = RTCT
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
A3967
Microstepping Driver with Translator
Functional Description (cont’d)
tBLANK = 1400CT
Enable Input (ENABLE). This active-low input enables
all of the outputs. When logic high the outputs are disabled. Inputs to the translator (STEP, DIRECTION, MS1,
MS2) are all active independent of the ENABLE input
state.
Shutdown. In the event of a fault (excessive junction
temperature) the outputs of the device are disabled until
the fault condition is removed. At power up, and in the
event of low VCC, the under-voltage lockout (UVLO)
circuit disables the drivers and resets the translator to the
home state.
Sleep Mode (SLEEP). An active-low control input used
to minimize power consumption when not in use. This disables much of the internal circuitry including the outputs.
A logic high allows normal operation and startup of the
device in the home position.
Typical output saturation voltages showing Satlington sink-driver operation.
Percent Fast Decay Input (PFD). When a STEP input
signal commands a lower output current from the previous
step, it switches the output current decay to either slow-,
fast-, or mixed-decay depending on the voltage level at the
PFD input. If the voltage at the PFD input is greater than
0.6VCC then slow-decay mode is selected. If the voltage on
the PFD input is less than 0.21VCC then fast-decay mode is
selected. Mixed decay is between these two levels.
Mixed Decay Operation. If the voltage on the PFD input is between 0.6VCC and 0.21VCC, the bridge will operate in mixed-decay mode depending on the step sequence
(see figures). As the trip point is reached, the device will
go into fast-decay mode until the voltage on the RC terminal decays to the voltage applied to the PFD terminal. The
time that the device operates in fast decay is approximated
by:
tFD = RTCTIn (0.6VCC/VPFD)
After this fast decay portion, tFD, the device will
switch to slow-decay mode for the remainder of the fixed
off-time period.
2.5
OUTPUT SATURATION VOLTAGE IN VOLTS
RC Blanking. In addition to the fixed off-time of the
PWM control circuit, the CT component sets the comparator blanking time. This function blanks the output of the
current-sense comparator when the outputs are switched by
the internal current-control circuitry. The comparator output is blanked to prevent false overcurrent detection due
to reverse recovery currents of the clamp diodes, and/or
switching transients related to the capacitance of the load.
The blank time tBLANK can be approximated by:
TA = +25°C
2.0
SOURCE DRIVER
1.5
1.0
0.5
SINK DRIVER
0
200
300
400
500
600
7 00
OUTPUT CURRENT IN MILLIAMPERES
Dwg. GP-064-1A
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
6
A3967
Microstepping Driver with Translator
Timing Requirements
(TA = +25°C, VCC = 5 V, Logic Levels are VCC and Ground)
STEP
50%
C
A
D
B
MS1/MS2/
DIR/RESET
E
SLEEP
Dwg. WP-042
A. Minimum Command Active Time
Before Step Pulse (Data Set-Up Time) ..... 200 ns
B. Minimum Command Active Time
After Step Pulse (Data Hold Time) ........... 200 ns
C. Minimum STEP Pulse Width ...................... 1.0 μs
D. Minimum STEP Low Time ......................... 1.0 μs
E. Maximum Wake-Up Time ......................... 1.0 ms
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
A3967
Microstepping Driver with Translator
Applications Information
Layout. The printed wiring board should use a heavy
ground plane.
For optimum electrical and thermal performance, the
driver should be soldered directly onto the board.
The load supply terminal, VBB, should be decoupled
with an electrolytic capacitor (>47 μF is recommended)
placed as close to the device as possible.
To avoid problems due to capacitive coupling of the
high dv/dt switching transients, route the bridge-output
traces away from the sensitive logic-input traces. Always
drive the logic inputs with a low source impedance to
increase noise immunity.
Grounding. A star ground system located close to the
driver is recommended.
The 24-lead SOIC has the analog ground and the
power ground internally bonded to the power tabs of the
package (leads 6, 7, 18, and 19).
Current Sensing. To minimize inaccuracies caused by
ground-trace IR drops in sensing the output current level,
the current-sense resistor (RS) should have an independent ground return to the star ground of the device. This
path should be as short as possible. For low-value sense
resistors the IR drops in the printed wiring board sense
resistor’s traces can be significant and should be taken into
account. The use of sockets should be avoided as they can
introduce variation in RS due to their contact resistance.
Allegro MicroSystems recommends a value of RS
given by
RS = 0.5/ITRIPmax
Thermal protection. Circuitry turns off all drivers when
the junction temperature reaches 165°C, typically. It is
intended only to protect the device from failures due to
excessive junction temperatures and should not imply that
output short circuits are permitted. Thermal shutdown has
a hysteresis of approximately 15°C.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
8
A3967
Microstepping Driver with Translator
Table 2. Step Sequencing
Home State = 45º Step Angle, DIR = H
Full Step
Half Step
¼ Step
ǩ Step
Phase 1 Current
(%Itripmax)
(%)
1
1
1
100.00
0.00
0.0
2
98.08
19.51
11.3
3
92.39
38.27
22.5
4
83.15
55.56
33.8
5
70.71
70.71
45.0
6
55.56
83.15
56.3
7
38.27
92.39
67.5
8
19.51
98.08
78.8
9
0.00
100.00
90.0
10
–19.51
98.08
101.3
11
–38.27
92.39
112.5
12
–55.56
83.15
123.8
13
–70.71
70.71
135.0
14
–83.15
55.56
146.3
15
–92.39
38.27
157.5
16
–98.08
19.51
168.8
17
–100.00
0.00
180.0
18
–98.08
–19.51
191.3
19
–92.39
–38.27
202.5
20
–83.15
–55.56
213.8
21
–70.71
–70.71
225.0
22
–55.56
–83.15
236.3
23
–38.27
–92.39
247.5
24
–19.51
–98.08
258.8
25
0.00
–100.00
270.0
26
19.51
–98.08
281.3
27
38.27
–92.39
292.5
28
55.56
–83.15
303.8
29
70.71
–70.71
315.0
30
83.15
–55.56
326.3
31
92.39
–38.27
337.5
32
98.08
–19.51
348.8
2
1
2
3
4
3
5
6
2
4
7
8
5
9
10
3
6
11
12
7
13
14
4
8
15
16
Phase 2 Current
(%Itripmax)
(%)
Step Angle
(º)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
9
A3967
Microstepping Driver with Translator
Full Step Operation
MS1 = MS2 = L, DIR = H
STEP
INPUT
SLOW
DECAY
70.7%
PHASE 1
CURRENT
–70.7%
SLOW
DECAY
70.7%
PHASE 2
CURRENT
–70.7%
Dwg. WK-004-19
The vector addition of the output currents at any step is
100%.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
10
A3967
Microstepping Driver with Translator
Half Step Operation
MS1 = H, MS2 = L, DIR = H
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
STEP
INPUT
100%
70.7%
PHASE 1
CURRENT
–70.7%
–100%
100%
70.7%
PHASE 2
CURRENT
–70.7%
–100%
Dwg. WK-004-18
The mixed-decay mode is controlled by the percent fast decay voltage (VPFD). If the voltage at the PFD input is greater than 0.6VCC then slow-decay mode is selected. If the voltage on the PFD input is less than 0.21VCC then fast-decay mode is selected. Mixed decay
is between these two levels.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
11
A3967
Microstepping Driver with Translator
Quarter Step Operation
MS1 = L, MS2 = H, DIR = H
STEP
INPUT
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
100%
70.7%
38.3%
PHASE 1
CURRENT
–38.3%
–70.7%
–100%
100%
70.7%
38.3%
PHASE 2
CURRENT
–38.3%
–70.7%
–100%
Dwg. WK-004-17
The mixed-decay mode is controlled by the percent fast decay voltage (VPFD). If the
voltage at the PFD input is greater than 0.6VCC then slow-decay mode is selected. If the
voltage on the PFD input is less than 0.21VCC then fast-decay mode is selected. Mixed
decay is between these two levels.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
12
A3967
Microstepping Driver with Translator
8 Microstep/Step Operation
MS1 = MS2 = H, DIR = H
STEP
INPUT
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
MIXED
DECAY
SLOW
DECAY
MIXED
DECAY
SLOW
DECAY
100%
70.7%
38.3%
PHASE 1
CURRENT
–38.3%
–70.7%
–100%
100%
70.7%
38.3%
PHASE 2
CURRENT
–38.3%
–70.7%
–100%
Dwg. WK-004-16
The mixed-decay mode is controlled by the percent fast decay voltage (VPFD). If the voltage at the PFD input is greater than 0.6VCC then slow-decay mode is selected. If the voltage on the PFD input is less than 0.21VCC then fast-decay mode is selected. Mixed decay
is between these two levels.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
13
A3967
Microstepping Driver with Translator
Pin-out Diagram
REF
1
RC 2
÷8
PWM
TIMER
24
PFD
2
23
RC 1
SLEEP
3
22
RESET
OUT2B
4
21
OUT1B
LOAD
SUPPLY 2
5
20
LOAD
SUPPLY 1
GND
6
19
GND
GND
VBB1
VBB2
7
18
GND
SENSE2
8
17
SENSE1
OUT2A
9
16
OUT1A
STEP
10
15
ENABLE
DIR
11
14
LOGIC
SUPPLY
MS1
12
13
MS2
Terminal List
TRANSLATOR
& CONTROL
LOGIC
VCC
Dwg. PP-075-2
Terminal
Name
Terminal Description
REF
RC2
SLEEP
OUT2B
LOAD SUPPLY2
GND
SENSE2
OUT2A
STEP
DIR
MS1
MS2
LOGIC SUPPLY
ENABLE
OUT1A
SENSE1
GND
LOAD SUPPLY1
OUT1B
RESET
RC1
PFD
Gm reference input
Analog input for fixed offtime – bridge 2
Logic input
H bridge 2 output B
VBB2, the load supply for bridge 2
Analog and power ground
Sense resistor for bridge 2
H bridge 2 output A
Logic input
Logic Input
Logic input
Logic input
VCC, the logic supply voltage
Logic input
H bridge 1 output A
Sense resistor for bridge 1
Analog and power ground
VBB1, the load supply for bridge 1
H bridge 1 output B
Logic input
Analog Input for fixed offtime – bridge 1
Mixed decay setting
Terminal
Number
1
2
3
4
5
6, 7
8
9
10
11
12
13
14
15
16
17
18, 19
20
21
22
23
24
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
14
A3967
Microstepping Driver with Translator
Package LB 24-Pin SOIC
15.40±0.20
4° ±4
24
+0.07
0.27 –0.06
10.30±0.33
7.50±0.10
A
1
24
2.20
9.60
+0.44
0.84 –0.43
2
1
2
0.65
0.25
24X
SEATING
PLANE
0.10 C
0.41 ±0.10
1.27
C
1.27
B PCB Layout Reference View
SEATING PLANE
GAUGE PLANE
2.65 MAX
0.20 ±0.10
For reference only
Pins 6 and 7, and 18 and 19 internally fused
Dimensions in millimeters
(Reference JEDEC MS-013 AD)
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
E t
dl d
fi
ti
t
li di
ti
ithi li it h
A Terminal #1 mark area
B Reference pad layout (reference IPC SOIC127P1030X265-24M)
All pads a minimum of 0.20 mm from all adjacent pads; adjust as necessary
to meet application process requirements and PCB layout tolerances
Copyright ©2002-2013, Allegro MicroSystems, LLC
The products described here are manufactured under one or more U.S. patents, including U. S. Patent No. 5,684,427, or U.S. patents pending
Allegro MicroSystems, LLC reserves the right to make, from time to time, such departures from the detail specifications as may be required to
permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that
the information being relied upon is current.
Allegro’s products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the
failure of that life support device or system, or to affect the safety or effectiveness of that device or system.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, LLC assumes no responsibility for its use;
nor for any infringement of patents or other rights of third parties which may result from its use.
For the latest version of this document, go to our website at:
www.allegromicro.com
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
15
Similar pages