2
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000;
A3967
Microstepping Driver with Translator
ELECTRICAL CHARACTERISTICS at TA = +25°C, VBB = 30 V, VCC = 3.0 V to 5.5V (unless otherwise noted)
VSENSE VREF
Output Current
IOUT
Package Power Dissipation
PD
Operating Ambient Temperature
TA
Maximum Junction Temperature TJ(max)
Storage Temperature
Tstg
Notes
5 VBB2
OUT2A 9
OUT2B 4
SENSE2 8
Dwg. FP-050-3A
26184.24H
A3967
Microstepping Driver with Translator
Selection Guide Part Number
A3967SLBTR-T
Packing 24-pin SOIC with internally fused pins
3
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000;
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)
Package 1000 per reel
Absolute Maximum Ratings
Characteristic
Symbol
Load Supply Voltage
VBB
Logic Supply Voltage
VCC
Logic Input Voltage Range
VIN
Sense Voltage Reference Voltage
toff
Operating
VIN = 0.7VCC VIN = 0.3VCC Rt = 56 kΩ, Ct = 680 pF Rt = 56 kΩ, Ct = 680 pF
Min.
4.75 0 – – – – – – – – – – –
3.0 0.7VCC
– -20 -20 500* 700 30
Typ. Max. Units
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.
LOGIC SUPPLY
VCC 14
REF. SUPPLY
REF 1
RC1 23
STEP 10 DIR 11
RESET 22 MS1 12 MS2 13
Functional Block Diagram
UVLO AND FAULT DETECT
÷8
DAC
+-
SENSE
PWM LATCH BLANKING MIXED DECAY
mA – ºC
ºC
ºC
Units ºC/W ºC/W
ALLOWABLE PACKAGE POWER DISSIPATION (W)
5
RQJT = 6.0oC/W
4
3
R QJA = 35°C/W
2
R QJA = 50°C/W
1
0 25
50
75
100
125
TEMPERATURE IN oC
150
Allegro MicroSystems, Inc.
Continuous Peak
See graph
Range S
Fault conditions that produce excessive junction temperature will activate the device’s thermal shutdown circuitry. These conditions can be tolerated but should be avoided.
tw > 30 ns tw < 30 ns
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.
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.
Sleep mode
Control Logic
Logic Supply Voltage Range Logic Input Voltage
Logic Input Current
Maximum STEP Frequency Blank Time Fixed Off Time
VCC VIN(1) VIN(0) IIN(1) IIN(0) fSTEP tBLANK
–
30
V
–
30
V
<1.0
20
μA
<-1.0 -20
μA
1.9
2.1
V
1.7
2.0
V
0.65
1.3
V
0.21
0.5
V
1.4
1.6
V
1.1
1.4
V
–
5.0
mA
–
200
μA
–
V
–
–
V
–
0.3VCC
V
<1.0
20
μA
<1.0
20
μA
–
–
kHz
950 1200
ns
38
46
μs
continued next page …
Internal circuit protection includes thermal shutdown with hysteresis, under-voltage lockout (UVLO) and crossovercurrent protection. Special power-up sequencing is not required.
3
PWM TIMER
TRANSLATOR CONTROL LOGIC
SLEEP 3 ENABLE 15
VPF
24 PFD
2 RC2
PWM TIMER
3
PWM LATCH
BLANKING
MIXED DECAY
DAC
+67
18 19
VBB1 20
LOAD SUPPLY
OUT1A 16
OUT1B 21
SENSE1 17
Table 1. Microstep Resolution Truth Table
MS1 L H L H
MS2 L L H H
Resolution Full step (2 phase)
Half step Quarter step Eighth step
Allegro MicroSystems, Inc.
ICEX VCE(sat)
Clamp Diode Forward Voltage VF
Motor Supply Current
IBB
VOUT = VBB VOUT = 0 V Source driver, IOUT = -750 mA Source driver, IOUT = -400 mA Sink driver, IOUT = 750 mA Sink driver, IOUT = 400 mA IF = 750 mA IF = 400 mA Outputs enabled RESET high