L6223A ST Microelectronics, Inc., L6223A Datasheet
L6223A
Related parts for L6223A
L6223A Summary of contents
Page 1
... LEVELS DUAL PWM FREQUENCY SELECTION INPUT BIDIRECTIONALLY PROTECTED THERMAL SHUTDOWN DESCRIPTION The L6223A is a programmable integrated sys- tem for driving a unipolar stepper motor real- ized in Multipower BCD technology. The DMOS BLOCK DIAGRAM October 1991 This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice. ...
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... PCB, see fig. 34 PIN CONNECTION ( top wiew ) THERMAL DATA R Thermal Resistance Junction-pins thj-pins R Thermal Resistance Junction-ambient thj-amb 2/33 L6223A. The L6223A is mounted in a 20-lead Powerdip package, (16+2+2). Four ground leads conduct heat to dedicated heatsink area on the PCB. Parameter = 90 C pins (**) amb ...
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... SIMPLIFIED MODE - IN1 and IN2 drive the phases,IN3 is ENABLE, IN4 works with DA/CLEV to enable the reduce current level. Previous programming not needed. Input for external RC network. Defines the higher of two possible chopping frequencies. If this pin is set to ground it will reset the IC. Logic supply. Output for sense resistor. L6223A 3/33 ...
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... L6223A ELECTRICAL CHARACTERISTICS ( 3.3nF, unless otherwise specified). Symbol Parameter V Power Supply S V Logic Supply SS I Power Supply Quiescent S Current I Logic Supply Quiescent SS Current I Output Leakage Curr Reset Threshold rs Voltage (Pin 14) T Bootstrap Refresh Pulse BOOT SINK MOS R ON Resistance ...
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... Min (Fig. 5) (load) Pure Resistive Load (Fig. 5) (load) Pure Resistive Load (Fig. 4) Note 1 (Fig. 6) 1.7 (Fig. 6) Note 2 0.2 (Fig (Fig. 6) 1.6 (Fig. 6) 200 Figure 2a: Source Output DMOS R Circuit L6223A Typ Max Unit 250 ns 700 Test DS(ON) 5/33 ...
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... L6223A Figure 2b: Sink Output DMOS R DS(ON) Figure 4: Sense Filter RC Time Constant and PWM Closed Loop control Circuit Figure 6: Programming Timing Diagram (see Block Diagram) 6/33 Figure 3: Typical normalized R Test Circuit temperature Figure 5: Output Sink Current Delay vs Input Control vs. Junction DS(ON) ...
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... For this transistor a charge pump circuit provides its necessary gate drive over voltage. The microprocessor outputs are interfaced with the L6223A output stages through the input logic block. This block also protects the device from mi- croprocessor output errors and failures from the power section back to the microprocessor out- puts ...
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... L6223A Table 1 Device status Bit C5 Simplified Phase A mode L operating Driver Full mode Phase A H operating Programming X mode Figure 7: Internal Six-Bit Shift Register Bit Functions CIRCUIT OPERATION (continued) The FULL OPERATING MODE permits all the driving possibilities. The 4 low side DMOS transis- ...
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... IN1...IN4 Low to carry a single bit. This per- mits the motor to be enabled for the 50% of total programming time. During the motor rotation it’s suggested to program the device immediately af- ter the motor phase change: this make neglect- able the motor driving discontinuity due to the de- vice programming. L6223A 9/33 ...
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... L6223A Operating Mode The bit C5 defines the two available input configu- rations FULL MODE OPERATING The digital inputs have the following functions: IN1 drives OUT1 The output DMOS is ON IN2 drives OUT2 when the corrisponding in- IN3 drives OUT3 put is low ...
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... Table discharge time percentage L6223A Operating Configuration vs. 6bits Shift Register Programming (External RC network 18k C = 3,3nF) SHIFT REGISTER bITS ...
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... The motor torque is proportional to the vectorial sum of the phase currents: it can be seen that the unipolar stepper motor control actu- ated by L6223A in half step is at constant torque but not at constat current. Close Loop Open Loop ...
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... Figure 10: Typical Application Circuit using a single device: the max peak current capability is of 1A/phase ( Figure 11: Inputs for Half Step drive, single device FMO. Figure 13: Inputs for Full Step drive single device SMO. Figure 12: Inputs for Full Step drive, single device FMO. L6223A 13/33 ...
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... L6223A Figure 14: Peak current 2I crossing the sense resistor Full Steps, 2 phase ON) Figure 15: Peak current (2I /2 phase ON) and reduced peak current (1.4I p resistor R in Half step drive. The phase sequence is Half Steps, 1 phase ON and 2 phases ON alternatively) Figure 16: Typical Application Circuit using 2 devices (Paralleled configuration): the max peak current ...
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... L6223A. The use of another configuration can cause serious demage to the IC during the pro- gramming. The waveforms required to drive the motor in half/full step are shown in Fig. 17 and 18 can be seen, the two L6223A are in SIMPLI /Ip) FIED MODE OPERATING configuration. The half ...
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... L6223A Figure 19: Dot Matrix Printer Motor Driver schematic diagram (See also fig. 10, 16). External RC Network (pin 14) The external RC network provides the higher of the two possible chopping frequencies. The dis- charge time of the capacitor represents the mini- mum t available in closed loop. In open loop it ...
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... Because of that, driving high speedy stepper mo- tors is produced a noisy beating between chop- ping frequency and phase change rate. In the L6223A as soon as the phase change is driven by the inputs, the oscillator voltage Jumps to its top level, a new discharge period is gener- ated and the chopping transistor is switched ON (Q5 in fig ...
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... During these events the L6223A can be pro- grammed several times for different working modes. The most important parameter is the cur- rent through the windings of the stepper: at the time ...
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... Rotation speed Peak of the BEMF Max ambient temperature T and t ON OFF Max junction temperature T From the Electrical Characteristics of the L6223A (Typical value): Internal Reference Voltage V Sink DMOS R Source DMOS R Power Supply Current Logic Supply Current From Fig. 3 (see pag. 6) the following is obtained: 1 ...
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... L6223A 1 DSON 0.7 = 1.15 DSON 12.5 tot V = 26.24V (During the chopping 9.7 (During the chopping) OFF DC = 15. msec 250 s (During the phase change) 1 PdL = 1.1W PdH = 0.4W Pdch = 0.20W Pdo = 0.24W At last 1.94W tot The needed thermal resistance between junction and ambient must be equal to: ...
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... Figure 26: Phase current waveform during chopping: the current decay during t Figure 27: Simplified waveforms of the current through the phase A (winding MA) and through the phase B (winding MB). See also fig.22. 55 C); the copper side C/W - See Fig. 34) and the additional heatsink ( C/W). thj-amb = thj-amb L6223A thj-amb is halved. OFF 21/33 ...
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... L6223A Figure 28a: Single L6223A slow speed, Application Data. Figure 28b: Total Power Dissipation. The vertical indicator tells us the max value of the current we can supply to the windings (Ip = 0.8A). The peak current corresponding to the flat side of each of the three shown trends is not allowed ...
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... Figure 29a: Single L6223A high speed, Application Data. Figure 29b: Total Power Dissipation. L6223A 23/33 ...
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... L6223A Figure 30a: Dual L6223A slow speed, Application Data. Figure 30b: Total Power Dissipation. 24/33 ...
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... Figure 31a: Dual L6223A high speed, Application Data. Figure 31b: Total Power Dissipation. L6223A 25/33 ...
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... L6223A in Single and Dual Device configuration is shown in Fig. 32a-b. Fig the correspond- ing electrical circuit. On the board are mounted three L6223A: two for the Dual Device configura- tion and one for the Single Device. The three con- nectors J1, J2, J3 allow the application board to be interfaced with the PC and to be paralleled with another one ...
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... Figure 32a: L6223A p.c.b. (components side). L6223A 27/33 ...
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... L6223A Figure 32b: L6223A p.c.b. (back side). 28/33 ...
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... Figure 33: L6223A Development Board schematic diagram. L6223A 29/33 ...
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... L6223A Figure 34: R with two ”on board” square heatsink vs. side I. th Figure 35: Transient thermal resistance for single pulses Thermal characteristics. The p.c.b. copper size needed for a defined ther- mal resistance between junction and ambient is shown in Fig. 34. Fig. 35 and Fig. 36 are useful to ...
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... The value of the boot- strap capacitor is not a critical parameter, never- theless the use of a capacitor of 10nF 20% is recommended. A non-inductive resistor is the best way to implement the sensing, but when that is not possible, more metalfilm resistors of the same value can be paralleled. L6223A . It’s impor- thj-amb 31/33 ...
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... L6223A POWERDIP20 PACKAGE MECHANICAL DATA DIM. MIN. a1 0. 32/33 mm TYP. MAX. MIN. 0.020 1.40 0.033 0.50 0.50 0.015 24.80 8.80 2.54 22.86 7.10 5.10 3.30 1.27 inch TYP. MAX. 0.055 0.020 0.020 0.976 0.346 0.100 0.900 0.280 0.201 0.130 0.050 ...
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... SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without ex- press 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. L6223A 33/33 ...