EVAL6229PD STMicroelectronics, EVAL6229PD Datasheet

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Modern motion control applications need more flexibility that can be addressed only with specialized IC products. The L6208 is a fully integrated stepper motor driver IC specifically developed to drive a wide range of two phase (bipolar) stepper motors. This ...

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AN1451 APPLICATION NOTE 1 INTRODUCTION ................................................................................................................................1 2 DESIGNING AN APPLICATION WITH L6208 ...................................................................................3 2.1 Current Ratings ........................................................................................................................3 2.2 Voltage Ratings and Operating Range ....................................................................................3 2.3 Choosing the Bulk Capacitor....................................................................................................5 2.4 Layout Considerations .............................................................................................................6 2.5 Sensing Resistors ....................................................................................................................8 2.6 Charge pump ...

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DESIGNING AN APPLICATION WITH L6208 2.1 Current Ratings With MOSFET (DMOS) devices, unlike bipolar transistors, current under short circuit conditions is, at first ap- proximation, limited by the R DS(ON) and the two V and V pins are rated ...

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AN1451 APPLICATION NOTE above V , due to the PCB inductance and voltage drop across the high-side (integrated) freewheeling diode the current reverses direction and flows into the bulk capacitor. It turns out that, in fast decay, the ...

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Figure 4. Voltage at the two outputs at the beginning of the off-time. 2.3 Choosing the Bulk Capacitor Since the bulk capacitor, placed between V AC current capability must be greater than the r.m.s. value of the charge/discharge current. This ...

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AN1451 APPLICATION NOTE For Example maximum ripple of 500mV is allowed and I Actually, current sunk by V and V SA charge of internal freewheeling diodes. Duration of these peaks is, tough, very short, and can be filtered ...

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High current GND tracks (i.e. the tracks connected to the sensing resistors) must be connected directly to the negative terminal of the bulk capacitor. A good quality, high-frequency bypass capacitor is also required (typi- cally a 100nF÷200nF ceramic would suffice), ...

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AN1451 APPLICATION NOTE 2.5 Sensing Resistors Each motor winding current is flowing through the corresponding sensing resistor, causing a voltage drop that is used, by the logic, to control the peak value of the load current. Two issues must be ...

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Charge pump external components An internal oscillator, with its output at CP pin, switches from GND to 10V with a typical frequency of 600kHz (see Figure 7). Figure 7. Charge Pump ...

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AN1451 APPLICATION NOTE 2.7 Sharing the Charge Pump Circuitry If more than one device is used in the application, it's possible to use the charge pump from one L6208 to supply the V pins of several ICs. The unused CP ...

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Reference Voltage for PWM Current Control The device has two analog inputs, V peak value of the motor current through the integrated PWM circuitry. In typical applications these pins are con- nected together, in order to obtain the same ...

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AN1451 APPLICATION NOTE 2.9 Input Logic pins CW/CCW, CONTROL, RESET, HALF/FULL, CLOCK are CMOS/TTL compatible logic input pins. The input compar- ator has been realized with hysteresis to ensure the required noise immunity. Typical values for turn-on and turn-off thresholds ...

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Programmable off-time Monostable The L6208 includes a constant off time PWM current controller for each of the two bridges. The current control circuit senses the bridge current by sensing the voltage drop across an external sense resistor connected be- ...

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AN1451 APPLICATION NOTE Figure 13. Output Current Regulation Waveforms I OUT V REF R SENSE V SENSE V REF 2.5V ON SYNCHRONOUS OR QUASI SYNCHRONOUS RECTIFICATION OFF D01IN1334 Figure 14 shows the magnitude of the Off ...

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MIN   t > – RCRISE DT  600 · C ...

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AN1451 APPLICATION NOTE 2.11.2 Decay Modes The CONTROL input is used to select the behavior of the bridge during the off time. When the CONTROL pin is low, the Fast Decay mode is selected and both transistors in the bridge ...

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In some conditions (short off-time, very low regulated current, high motor winding the system may need an on-time shorter than 1.5µs. In these cases the PWM current controller can loose the regulation. Figure 17 shows the operation ...

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AN1451 APPLICATION NOTE 2.12 Over Current Protection To implement an Over Current (i.e. short circuit) Protection, a dedicated Over Current Detection (OCD) circuitry (see Figure 18 for a simplified schematic) senses the current in each high side. Power DMOS are ...

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Figure 19. Over Current Operation. t DELAY t OCD(ON OVER t EN(FALL) t D(OFF)EN V TH(OFF) t OCD(OFF) The maximum value reached by the current depends on its slew-rate the short circuit nature and supply voltage, ...

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AN1451 APPLICATION NOTE applied The external RC network particular, must be chosen obtaining a reasonable fast OCD intervention (short and a safe disable time (long t DELAY at least 100µs for ...

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Power Management Even when operating at current levels well below the maximum ratings of the device, the operating junction tem- perature must be kept below 125 °C. Figure 21 shows the IC dissipated power versus the r.m.s. load current, ...

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AN1451 APPLICATION NOTE 2.13.1 Maximum output current vs. selectable devices Figure 22 reports a performance comparison between L6228 (std. power) and L6208 (high power) for different packages, with the following assumptions: - Normal Drive Mode (two-phase on) - Supply voltage: ...

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Figure 23. Definition of parameters for the three different sequences. The current in only one phase is shown. NORMAL load load I T Figure 24. Input Data. Device Input Values Maximum Drain-Source ...

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AN1451 APPLICATION NOTE Figure 25. Power Dissipation formulae and results. Result PowerDMOS Commutation Tcom = 9.60E-08 Time Rise Time Trise = 4.03E-04 Fall Time Tfall = 3.16E-04 Duty Cycle D = 6.25E-01 Switching fSW = 2.50E+04 Frequency Current Ripple I ...

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Figure 26. Thermal Data inputs and results. Package Copper Area Copper Area is on Ground Layer Am bient Tem perature Therm al Resistance Junction to Am bient Therm al Resistance Junction to Pins / Slug Estim ated Junction Tem perature ...

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AN1451 APPLICATION NOTE 2.15 Choosing the Stepping Sequence The device can provide three different sequences to run a stepper motor: full step two phase on (Normal drive), full step one phase on (Wave drive) and Half step. If Half Step ...

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A simple circuit to generate two different reference voltages is shown in Figure 29 have and R should similar circuit can also be used to modify the reference voltage in other situations. For example it's ...

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AN1451 APPLICATION NOTE Figure 30. Microstepping Application. µ C Figure 31. Microstepping reference voltages, output currents and CLOCK signal MAX SENSE MAX SENSE MAX -I MAX . ...

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Figure 32. Using Fast decay during high negative current slope. V refA V refB I outA I outB CONTROL CLOCK 5V 0V Fast Decay Selected AN1451 APPLICATION NOTE Slow Decay Selected 29/43 ...

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AN1451 APPLICATION NOTE 3 APPLICATION EXAMPLE Application Data Rotation Speed: 300 rpm (f Winding peak Current: 1A Maximum Ripple: 50mA Supply Voltage: 24V ±5% Sequence: Wave Mode 3.1 Decay mode, sensing resistors and reference voltage. The first step is choosing ...

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APPENDIX - EVALUATION BOARDS 4.1 PractiSPIN PractiSPIN is an evaluation and demonstration system that can be used with the PowerSPIN family (L62XX) of devices. A Graphical User Interface (GUI) (see Figure 34) program runs on an IBM-PC under windows ...

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AN1451 APPLICATION NOTE Figure 35. PractiSPIN ST7 Evaluation Board 32/43 ...

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EVAL6208N An evaluation board has been produced to help the evaluation of the device in PowerDIP package. It imple- ments a typical application with several added components. Figure 37 shows the electrical schematic of the board; in the table ...

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AN1451 APPLICATION NOTE Figure 36. EVAL6208N 4.2.1 Important Notes JP1 : close in INT position for use with PractiSPIN ST7 board C6 : recommended change to 5.6 nF for safe Overcurrent protection R8 : recommended change to 100 ...

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Figure 37. EVAL6208N Electrical schematic. CN1 CN2 GND JP1 2 + CCW ...

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AN1451 APPLICATION NOTE Figure 38. EVAL6208N Component placement. Figure 39. EVAL6208N Top Layer Layout. Signal GND 36/43 Bulk Capacitor Power GND ...

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Figure 40. EVAL6208N Bottom Layer Layout. Figure 41. EVAL6208N Thermal impedance Junction to Ambient and pulsed Thermal impedance Junction to Ambient J J-A 20 [ºC/ ...

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AN1451 APPLICATION NOTE 4.3 EVAL6208PD An evaluation board has been produced to help the evaluation of the device in PowerSO package. It implements a typical application with several added components. Figure 43 shows the electrical schematic of the board; in ...

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Figure 42. EVAL6208PD. R7 4.3.1 Important Notes JP1 : close in INT position for use with PractiSPIN ST7 board C12 : recommended change to 5.6 nF for safe Overcurrent protection R7 : recommended change to 100 k for safe Overcurrent ...

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AN1451 APPLICATION NOTE Figure 43. EVAL6208PD Electrical schematic. CN1 CN2 R1 D2 VCCREF C5 JP1 JUMPER 3x1 2 +5V C3 VIN 33 C4 R18 GND ...

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Figure 44. EVAL6208PD Component placement. Figure 45. EVAL6208PD Top Layer Layout. AN1451 APPLICATION NOTE 41/43 ...

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AN1451 APPLICATION NOTE Figure 46. EVAL6208PD Bottom Layer Layout. Figure 47. EVAL6208PD Thermal impedance Junction to Ambient and pulsed Thermal impedance Junction to Ambient J J-A [ºC/ ...

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