PBL3717A STMICROELECTRONICS | Alldatasheet
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.FULL STEP - HALF STEP - QUARTER STEP OPERATING MODE .BIPOLAR OUTPUT CURRENT UP TO 1 A .FROM 10 V UP TO 46 V MOTOR SUPPLY VOLTAGE .LOW SATURATION VOLTAGE WITH INTE- GRATED BOOTSTRAP .BUILT IN FAST PROTECTION DIODES .EXTERNALLY SELECTABLE CURRENT LEVEL .OUTPUT CURRENT LEVEL DIGITALLY OR ANALOGUE CONTROLLED .THERMAL PROTECTION WITH SOFT INTER- VENTION Powerdip 12 + 2 + 2 (Plastic Package) ORDER CODE : PBL3717A
DESCRIPTION
The PBL3717Ais a monolithic IC which controlsand drives one phase of a bipolar stepper motor with choppercontrol of the phase current. Current levels maybe selected in threestepsbymeans oftwo logic inputs which select one of three current compara- tors. When both of these inputs are high the device is disabled. A separatelogic inputcontrols the direc- tion of current flow. A monostable, programmed by an external RC net- work, sets the current decay time. The power section is a full H-bridge driver with four internal clamp diodes for current recirculation. An externalconnectionto thelower emitters is available for the insertion of a sensing resistor. Two PBL3717As and few external components form a complete stepper motor drive subsystem. The raccomended operating ambient temperature ranges is from 0 to 70°C. The PBL3717Ais supplied in a 12 + 2 + 2 lead Pow- erdip package. PIN CONNECTION (top view)
N ° Name Function 1 UTPUT B Output Connection (with pin 15). The output stage is a ”H” bridge formed by four transistors and four diodes suitable for switching applications.
2 PULSE TIME A parallel RC network connected to this pin sets the OFF time of the lower power
transistors. The pulse generator is a monostable triggered by the rising edge of the output of the comparators (t off= 0.69 RT C T).
3 SUPPLY VOLTAGE B Supply Voltage Input for Half Output Stage
See also pin 14. 4 GROUND Ground Connection. With pins 5, 12 and 13 also conducts heat from die to printed circuit copper. 5 GROUND See pin 4.
6 LOGIC SUPPLY Supply Voltage Input for Logic Circuitry
7 INPUT 1 This pin and pin 9 (INPUT 0) are logic inputs which select the outputs of the
three comparators to set the current level. Current also depends on the sensing resistor and reference voltage. See truth table.
8 PHASE This TTL-compatible logic input sets the direction of current flow through the
load. A high level causes current to flow from OUTPUT A (source) to OUTPUT B (sink). A schmitt trigger on this input provides good noise immunity and a delay circuit prevents output stage short circuits during switching. 9 INPUT 0 See INPUT 1 (pin 7) .
10 COMPARATOR
Input connected to the three comparators. The voltage across the sense resistor is feedback to this input through the low pass filter R C C C . The lower power transistor are disabled when the sense voltage exceeds the reference voltage of the selected comparator. When this occurs the current decays for a time set by R T C T,toff= 0.69 RT C T.
11 REFERENCE A voltage applied to this pin sets the reference voltage of the three comparators,
this determining the output current (also thus depending on Rs and the two inputs INPUT 0 and INPUT 1). 12 GROUND See pin 4. 13 GROUND See pin 4. 14 SUPPLY VOLTAGE A Supply Voltage Input for Half Output Stage. See also pin 13. 15 OUTPUT A See pin 1.
16 SENSE RESISTOR Connection to Lower Emitters of Output Stage for Insertion of Current Sense
Input 0 (pin 9) Input 1 (pin 7) H L H L H H L L No Current Low Current Medium Current High Current PBL3717A
Symbol Parameter Value Unit Vs Power Supply Voltage 50 V Vss Logic Supply Voltage 7 V Vi Logic Input Voltage 6 V Vc Comparator Input V ss Vr Reference Input Voltage 15 V Io Output Current (DC operation) 1.2 A Tstg Storage Temperature – 55 to + 150 °C Tj Operating Junction Temperature 150 °C THERMAL DATA Symbol Parameter Value Unit R th j-case Thermal Resistance Junction-pins 11 °C/W R th j-amb Thermal Resistance Junction-ambient* 40 °C/W * Soldered on a 35µ thick 20 cm2 P.C. board coppe r area. PBL3717A
ELECTRICAL CHARACTERISTICS
(refer to the test circuit VS = 36V, VSS = 5V, Tamb =2 5oC unless otherwise specified) Symbol Parameter Test Conditions Min. Typ. Max. Unit Vs Supply Voltage (pin 3, 14) 10 46 V Vss Logic Supply Voltage (pin 6) 4.75 5.25 V Iss Logic Supply Current (pin 6) 7 15 mA IR Reference Input Current (pin 11) V R = 5V 0.75 1 mA LOGIC INPUTS ViL Input Low Voltage (pins 7, 8, 9) 0.8 V ViH Input High Voltage (pin 7, 8, 9) 2 V ss V IiL Low Voltage Input Current (pins 7, 8, 9) Vi= 0.4V pin 8 pins 7, 9 – 100 – 400 µA µA IiH High Voltage Input Current (pins 7, 8, 9) Vi= 2.4V 10 µA COMPARATORS VCL Comparator Low Threshold Voltage (pin 10) VR =5 V I o =L I1 =H 66 78 90 mV VCM Comparator Medium Threshold Voltage (pin 10) VR =5 V I o =L I1 =H 236 251 266 mV VCH Comparator High Threshold Voltage (pin 10) VR =5 V I o =L I1 =H 396 416 436 mV IC Comparator Input Current (pin 10) ± 20 µA toff Cutoff Time R T = 56kΩ C T = 820pF 25 35 µs td Turn Off Delay (see fig. 2) 2 µs Ioff Output Leakage Current (pins 1, 15) I o =H I 1 = H 100 µA SOURCE DIODE-TRANSISTOR PAIR Vsat Saturation Voltage (pins 1, 15) I M = – 0.5A (see fig. 2) Conduction Period Recirculation Period 1.7 1.1 2.1 1.35 V V sat Saturation Voltage (pins 1, 15) I M = – 1A (see fig. 2) Conduction Period Recirculation Period 2.1 1.7 2.8 2.5 V I LK Leakage Current V s = 46 V 300 µA VF Diode Forward Voltage I M = – 0.5A IM =–1 A 1.3 1.25 1.7 V V ISLK Substrate Leakage Current when Clamped I M = – 0.5A IM =–1 A mA mA SINK DIODE-TRANSISTOR PAIR Vsat Saturation Voltage (pins 1, 15) I M = 0.5A IM =1 A 1.1 1.6 1.35 2.3 V V ILK Leakage Current V s = 46V 300 µA VF Diode Forward Voltage I M = 0.5A IM =1 A 1.1 1.4 1.5 V V PBL3717A
L ≈ 1
10 LM C ≈ 4 ⋅10−10
L Quarter Step Operation It is preferable to realize the quarter step operation at full power otherwise the steps will be of very ir- regular size. The extra quarter steps are added to the half steps sequenceby puttingone coil on half current accord- ing to the sequence. AB → A
2 B → B → A
2 B → AB → A B
2 → A etc. Motor Selection As the PBL3717A provides constant current drive, with a switching operation, care must be takento se- lect stepper motors with low hysteresis losses to prevent motor over heat. L -C Filter To reduce EMI and chopping losses in the motor a low pass L -C filter can be inserted across the out- puts ofthePBL3717Aasshownon the followingpic- ture. Figure 6 :Source Saturation Voltage versus Output Current (recircuit period) Figure 7 :Source SaturationVoltage versus Output Current (conduction period) Figure 9 :Comparator Threshold versus Junction Temperature Figure 8 :Sink Saturation Voltage versus Output Current PBL3717A
POWERDIP16 PACKAGE MECHANICAL DATA DIM. mm inch a1 0.51 0.020 B 0.85 1.40 0.033 0.055 b 0.50 0.020 b1 0.38 0.50 0.015 0.020 D 20.0 0.787 E 8.80 0.346 e 2.54 0.100 e3 17.78 0.700 F 7.10 0.280 I 5.10 0.201 L 3.30 0.130 Z 1.27 0.050 PBL3717A
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifica- tions mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information pre- viously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics. 1994 SGS-THOMSON Microelectronics - All Rights Reserved SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thaliand - United Kingdom - U.S.A. PBL3717A