L6235QTR STMicroelectronics, L6235QTR Datasheet

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Features ■ Operating supply voltage from ■ 5.6 A output peak current 0.3 Ω typ. value @ T ■ R DS(on) ■ Operating frequency up to 100 kHz ■ Non-dissipative overcurrent protection ■ Diagnostic output ■ ...

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Contents Contents 1 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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L6235Q 1 Electrical data 1.1 Absolute maximum ratings Table 1. Absolute maximum ratings Symbol V Supply voltage S Differential voltage between OUT1 OUT1 B V Bootstrap peak voltage BOOT V ,V Input and ...

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Pin connection 2 Pin connection Figure 2. Pin connection (top view) TACHO Note: The exposed PAD must be connected to GND pin. Table 3. Pin description Pin Name 43 H1 Sensor input Open drain 44 DIAG 45, 46 SENSE Power ...

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L6235Q Table 3. Pin description (continued) Pin Name 15, 16 SENSE Power supply B 17 FWD/REV Logic input 18 EN Logic input 19 VREF Logic input 20 BRAKE Logic input 21 VBOOT Supply voltage Bootstrap voltage needed for driving the ...

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Electrical characteristics 3 Electrical characteristics °C, unless otherwise specified Table 4. Electrical characteristics Symbol Parameter V Turn-on threshold Sth(ON) V Turn-off threshold Sth(OFF) I Quiescent supply current S T Thermal shutdown ...

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L6235Q Table 4. Electrical characteristics (continued) Symbol Parameter (2) t Output rise time RISE (2) t Output fall time FALL t Dead time protection DT f Charge pump frequency CP PWM comparator and monostable I Source current at pin RC ...

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Electrical characteristics Figure 3. Switching characteristic definition EN V th(ON) V th(OFF) I OUT 90% 10% D01IN1316 Figure 4. Overcurrent detection timing definition 8/33 t D(OFF)EN I OUT I SOVER ON BRIDGE OFF V DIAG 90% 10% t OCD(ON) Doc ...

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L6235Q 4 Circuit description 4.1 Power stages and charge pump The L6235Q integrates a 3-phase bridge, which consists of 6 power MOSFETs connected as shown in Figure with intrinsic fast freewheeling diode. Switching patterns are generated by the PWM current ...

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Circuit description 4.2 Logic inputs Pins FWD/REV, BRAKE, EN, H1, H2 and H3 are TTL/CMOS and µC compatible logic inputs. The internal structure is shown in thresholds are respectively V Pin EN (enable) may be used to implement overcurrent and ...

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L6235Q 4.3 PWM current control The L6235Q includes a constant OFF time PWM current controller. The current control circuit senses the bridge current by sensing the voltage drop across an external sense resistor connected between the source of the three ...

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Circuit description Figure 10. Output current regulation waveforms I OUT V REF R SENSE V SENSE V REF 2.5V ON SYNCHRONOUS RECTIFICATION OFF D02IN1351 Figure 11 shows the magnitude of the OFF time t be approximately ...

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L6235Q Figure 12 shows the lower limit for the ON time t regulation capacity. It should be mentioned that t the device imposes this condition, but it can be smaller than t the device continues to work but the OFF ...

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Circuit description Figure 12. Area where t 14/33 can vary maintaining the PWM regulation ON 100 10 1.5μs (typ. value Coff [nF] Doc ID 018997 Rev 2 L6235Q ...

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L6235Q 4.4 Slow decay mode Figure 13 shows the operation of the bridge in slow decay mode during the OFF time. At any time only two legs of the 3-phase bridge are active, therefore, only the two active legs of ...

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Circuit description Table 6. 60 and 120 electrical degree decoding logic in forward direction Hall 120° Hall 60° OUT1 Vs OUT2 High Z OUT3 GND Phasing 1->3 Figure 14. 120° Hall sensor sequence ...

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L6235Q where C should be chosen in the range 1 nF … 100 nF and R PUL 100 kΩ. By connecting the tachometer pin to an external pull-up resistor, the output signal average value VM is proportional to the frequency ...

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Circuit description Figure 18. t PULSE 4.7 Non-dissipative overcurrent detection and protection The L6235Q integrates an overcurrent detection circuit (OCD) for full protection. With this internal overcurrent detection, the external current sense resistor normally used and its associated power dissipation ...

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L6235Q Figure 19. Overcurrent protection simplified schematic μC or LOGIC DIAG Figure 20 shows the overcurrent detection operation. The disable time t recovering normal operation can be easily programmed by means of the ...

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Circuit description Figure 20. Overcurrent protection waveforms I SOVER th(ON) V th(OFF) OCD BRIDGE 20/33 I OUT DIAG OFF ON t DELAY OFF OCD(ON) EN(FALL) OCD(OFF) t D(OFF)EN Doc ID ...

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L6235Q Figure 21. t DISABLE Figure 22. t DELAY 10 1 0.1 1 vs. C and ...

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Circuit description 4.8 Thermal protection In addition to the overcurrent detection, the L6235Q integrates a thermal protection to prevent device destruction in case of junction overtemperature. It works sensing the die temperature by means of a sensitive element integrated in ...

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L6235Q 5 Application information A typical application using L6235Q is shown in application are shown in 200 nF should be placed between the power pins (VS L6235Q to improve the high frequency filtering on the power supply and reduce high ...

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Application information Figure 23. Typical application + 8-52V DC POWER GROUND - SIGNAL GROUND THREE-PHASE MOTOR HALL SENSOR + Note: To reduce the IC thermal resistance, therefore improving ...

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L6235Q 6 Output current capability and IC power dissipation Figure 24 shows the approximate relation between the output current and the IC power dissipation using PWM current control. For a given output current the power dissipated by the IC can ...

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Thermal management 7 Thermal management In most applications the power dissipation in the IC is the main factor that sets the maximum current that can be delivered by the device in a safe operating condition. Selecting the appropriate package and ...

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L6235Q 8 Electrical characteristics curves Figure 25. Typical quiescent current vs. supply voltage 5 1kHz sw 5.4 5.2 5.0 4.8 4 [V] S Figure 27. Normalized typical quiescent current vs. ...

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Electrical characteristics curves Figure 29. Typical low-side R voltage R [Ω] DS(ON) 0.300 0.296 T = 25°C j 0.292 0.288 0.284 0.280 0.276 28/33 vs. supply Figure 30. Typical drain-source diode forward DS(on) I ...

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L6235Q 9 Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at: www.st.com. ...

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Package mechanical data Figure 31. VFQFPN48 ( 1.0 mm) package outline 30/33 Doc ID 018997 Rev 2 L6235Q ...

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... L6235Q 10 Order codes Table 9. Ordering information Order codes L6235Q L6235QTR Package QFN48 1.0 mm Doc ID 018997 Rev 2 Order codes Packaging Tray Tape and reel 31/33 ...

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Revision history 11 Revision history Table 10. Document revision history Date 30-Jul-2011 28-Nov-2011 32/33 Revision 1 First release 2 Document moved from preliminary to final datasheet Doc ID 018997 Rev 2 L6235Q Changes ...

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... L6235Q Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...