L6219 STMICROELECTRONICS | Alldatasheet
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ABLE TO DRIVE BOTH WINDINGS OF BIPO- LAR STEPPER MOTOR OUTPUT CURRENT UP TO 750mA EACH WINDING WIDE VOLTAGE RANGE 10V TO 46V HALF-STEP, FULL-STEP AND MICROSTEPP- ING MODE BUILT-IN PROTECTION DIODES INTERNAL PWM CURRENT CONTROL LOW OUTPUT SATURATION VOLTAGE DESIGNED FOR UNSTABILIZED MOTOR SUPPLY VOLTAGE INTERNAL THERMAL SHUTDOWN
DESCRIPTION
The L6219 is a bipolar monolithic integrated cir- cuits intended to control and drive both winding of a bipolar stepper motor or bidirectionally control two DC motors. The L6219 with a few external components form a complete control and drive circuit for LS-TTL or microprocessor controlled stepper motor system. The power stage is a dual full bridge capable of sustaining 46V and including four diodes for cur- rent recirculation. A cross conduction protection is provided to avoid simultaneous cross conduction during switching current direction. An internal pulse-width-modulation (PWM) con- trols the output current to 750mA with peak start- up current up to 1A. Wide range of current control from 750mA (each bridge) is permitted by means of two logic inputs and an external voltage reference. A phase input to each bridge determines the load current direction. A thermal protection circuitry disables the outputs if the chip temperature exceeds safe operating limits. October 2001 Powerdip 20+2+2 SO20+2+2 ORDERING NUMBERS: L6219 L6219DS BLOCK DIAGRAM
PDIP & SO Name Function 1;2 OUTPUT A See pins 5;21 3;23 SENSE RESISTOR Connection to Lower Emitters of Output Stage for Insertion of Current Sense Resistor 4;22 COMPARATOR INPUT Input connected to the comparators. The voltage across the sense resistor is feedback to this input throught the low pass filter RC CC. The higher power transistors 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 CT (toff = 1.1 RT C T). See fig. 1. 5;21 OUTPUT B Output Connection. The output stage is a "H" bridge formed by four transistors and four diodes suitable for switching applications. 6;19 GROUND See pins 7;18 7;18 GROUND Ground Connection. With pins 6 and 19 also conducts heat from die to printed circuit copper. 8;20 INPUT 0 See INPUT 1 (pins 9;17) 9;17 INPUT 1 These pins and pins 8;20 (INPUT 0) are logic inputs which select the outputs of the comparators to set the current level. Current also depends on the sensing resistor and reference voltage. See Funcional Description. 10;16 PHASE This TTL-compatible logic inputs 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. 11;15 REFERENCE VOLTAGE A voltage applied to this pin sets the reference voltage of the comparators, this determining the output current (also thus depending on R s and the two inputs INPUT 0 and INPUT 1). 12;14 RC A parallel RC network connected to this pin sets the OFF time of the higher power transistors. The pulse generator is a monostable triggered by the output of the comparators (toff = 1.1 RT CT).
13 V ss - LOGIC SUPPLY Supply Voltage Input for Logic Circuitry
24 Vs - LOAD SUPPLY Supply Voltage Input for the Output Stages. Note: ESD on GND, VS, VSS , OUT 1A and OUT 2A is guaranteed up to 1.5KV (Human Body Model, 1500Ω , 100pF). PIN CONNECTION (Top view) Powerdip and SO L6219
Symbol Parameter Value Unit VS Supply Voltage 50 V Io Output Current (peak) ±1A Io Output Current (continuous) ±0.75 A VSS Logic Supply Voltage 7 V VIN Logic Input Voltage Range -0.3 to +7 V Vsense Sense Output Voltage 1.5 V TJ Junction Temperature +150 °C Top Operating Temperature Range -20 to +85 °C Tstg Storage Temperature Range -55 to +150 °C THERMAL DATA Symbol Description PDIP SO Unit R thj-case R thj-amb Thermal Resistance Junction-case Max. Thermal Resistance Junction-ambient Max. 60 (*) 75 (*) °C/W °C/W (*) With minimized copper area. ELECTRICAL CHARACTERISTICS (Tj = 25°C, VS = 46V, VSS = 4.75V to 5.25V, VREF = 5V; unless oth- erwise specified) See fig. 3. Symbol Parameter Test Condition Min. Typ. Max. Unit OUTPUT DRIVERS (OUT A or OUTB) VS Motor Supply Range 10 46 V ICEX Output Leakage Current V OUT = Vs VOUT = 0 <-1 -50 µA µA VCE(sat) Output Saturation Voltage Sink Driver, IOUT = +500mA Sink Driver, IOUT = +750mA Source Driver, IOUT = -500mA Source Driver, IOUT = -750mA 0.3 0.7 1.1 1.3 0.6 1.4 1.6 V V V V I R Clamp Diode Leakage Current V R = 50V - <1 50 µA VF Clamp Diode Forward Voltage Sink Diode Source Diode IF =750mA 1.5 1.5 V V IS(on) Driver Supply Current Both Bridges ON, No Load - 8 15 mA IS(off) Driver Supply Current Both Bridges OFF - 6 10 mA CONTROL LOGIC VIN(H) Input Voltage All Inputs 2.4 - - V VIN(L) Input Voltage All Inputs - - 0.8 V IIN(H) Input Current VIN = 2.4V - <1 20 µA IIN(L) Input Current VIN = 0.84V - -3 -200 µA VREF Reference Voltage Operating 1.5 - 7.5 V ISS(ON) Total Logic Supply Current I o = I1 = 0.8V, No Load - 64 74 mA ISS(OFF) Total Logic Supply Current I o = I1 = 2.4V, No Load - 10 14 mA COMPARATORS VREF / Vsense Current Limit Threshold (at trip point Io = I1 = 0.8V 9.5 10 10.5 - Io = 2.4V, I1 = 0.8V 13.5 15 16.5 - Io = 0.8V, I1 = 2.4V 25.5 30 34.5 - toff Cutoff Time Rt = 56K Ω C t = 820pF - 50 s td Turn Off Delay Fig. 1 - 1 s µ µ L6219
The circuit is intended to drive both windings of a bipolar stepper motor. The peak current control is generated through switch mode regulation. There is a choice of three different current levels with the two logic inputs I 01 - I11 for winding 1 and I02 - I12 for winding 2. The current can also be switched off completely Input Logic (I0 and I1) The current level in the motor winding is selected with these inputs. (See fig. 2) If any of the logic inputs is left open, the circuit will treat it has a high level input. I0 I1 Current Level H H No Current L H Low current V 3 IO max H L Medium current 2/3 I O max L L Maximum current I O max Phase This input determines the direction of current flow in the windings, depending on the motor connec- tions. The signal is fed through a Schmidt-trigger for noise immunity, and through a time delay in order to guarantee that no short-circuit occurs in the output stage during phase-shift. High level on the PHASE input causes the motor current flow from Out A through the winding to Out B Current Sensor This part contains a current sensing resistor (R S), a low pass filter (RC , CC ) and three comparators. Only one comparator is active at a time. It is acti- vated by the input logic according to the current level chosen with signals Io and I1. The motor current flows through the sensing re- sistor RS. When the current has increased so that the volt- age across RS becomes higher than the refer- ence voltage on the other comparator input, the comparator goes high, which triggers the pulse generator. The max peak current I max can be defined by: Imax = Vref 10 Rs Single-pulse Generator The pulse generator is a monostable triggered on the positive going edge of the comparator output. The monostable output is high during the pulse time, toff , which is determined by the time compo- nents Rt and Ct. toff = 1.1 ⋅ RtC t The single pulse switches off the power feed to the motor winding, causing the winding current to decrease during toff. If a new trigger signal should occur during toff, it is ignored. Output Stage The output stage contains four Darlington transis- tors (source drivers) four saturated transistors (sink drivers) and eight diodes, connected in two H bridge. Figure 1 ELECTRICAL CHARACTERISTICS (Continued) Symbol Parameter Test Condition Min. Typ. Max. Unit PROTECTION TJ Thermal Shutdown Temperature - 170 - °C L6219
The source transistors are used to switch the power supplied to the motor winding, thus driving a constant current through the winding. It should be noted however, that is not permitted to short circuit the outputs. Internal circuitry is added in order to increase the accuracy of the motor current particularly with low current levels. VS, VSS , VRef The circuit will stand any order of turn-on or turn- off the supply voltages VS and VSS . Normal dV/dt values are then assumed. Preferably, VRef should be tracking VSS during power-on and power-off if VS is established. APPLICATION INFORMATIONS (Note 1) Some stepper motors are not designed for contin- uous operation at maximum current. As the circuit drives a constant current through the motor, its temperature might increase exceedingly both at low and high speed operation. Also, some stepper motors have such high core losses that they are not suited for switch mode Figure 2: Principle Operating Sequence L6219
current regulation. Unused inputs should be connected to proper voltage levels in order to get the highest noise im- munity. As the circuit operates with switch mode current regulation, interference generation problems might arise in some applications. A good measure might then be to decouple the circuit with a 100nF capacitor, located near the package between power line and ground. The ground lead between R s, and circuit GND should be kept as short as possible. A typical Application Circuit is shown in Fig. 3. Note that Ct must be NPO type or similar else. To sense the winding current, paralleled metal film resistors are recommended (Rs) Note 1 - Other information is available as "Smart Power Development System": Test board HWL6219 (Stepper driver) Software SWL6219 (Floppy disc) Figure 3: Typical Application Circuit. (Pin out referred to DIP24 package) L6219
DIM. mm inch A 4.320 0.170 A1 0.380 0.015 A2 3.300 0.130 E 7.620 8.260 0.300 0.325 e 2.54 0.100 e1 7.620 0.300 L 3.180 3.430 0.125 0.135 M 0˚ min, 15˚ max. Powerdip 24 B eB1 D L A c SDIP24L M OUTLINE AND MECHANICAL DATA L6219
DIM. mm inch A 2.35 2.65 0.093 0.104 A1 0.10 0.30 0.004 0.012 A2 2.55 0.100 B 0.33 0.51 0.013 0.0200 C 0.23 0.32 0.009 0.013 D 15.20 15.60 0.598 0.614 E 7.40 7.60 0.291 0.299 e 1.27 0,050 H 10.0 10.65 0.394 0.419 h 0.25 0.75 0.010 0.030 k0 ° (min.), 8° (max.) L 0.40 1.27 0.016 0.050 Be A2 A 1324 D L H A1 C E K h x 45˚ SO24 Seating Plane 0.10mm .004 OUTLINE AND MECHANICAL DATA L6219
Information furnished is believed to be accurate and reliable. However, STMicroelectronics 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 STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics © 2001 STMicroelectronics – Printed in Italy – All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com L6219