TCA3727 SIEMENS | Alldatasheet

Document overview

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Technical content

Features

  • 2 x 0.75 amp. / 50 V outputs
  • Integrated driver, control logic and current control (chopper)
  • Fast free-wheeling diodes
  • Max. supply voltage 52 V
  • Outputs free of crossover current
  • Offset-phase turn-ON of output stages
  • Z-diode for logic supply
  • Low standby-current drain
  • Full, half, quarter, mini step P-DIP-20-6 P-DSO-24-3

Description

TCA 3727 is a bipolar, monolithic IC for driving bipolar stepper motors, DC motors and other inductive loads that operate on constant current. The control logic and power output stages for two bipolar windings are integrated on a single chip which permits switched current control of motors with 0.75 A per phase at operating voltages up to 50 V. Type Ordering Code Package TCA 3727 Q67000-A8302 P-DIP-20-6 TCA 3727 G Q67000-A8335 P-DSO-24-3

Semiconductor Group 2 1998-02-01 The direction and value of current are programmed for each phase via separate control inputs. A common oscillator generates the timing for the current control and turn-on with phase offset of the two output stages. The two output stages in a full-bridge configuration have integrated, fast free-wheeling diodes and are free of crossover current. The logic is supplied either separately with 5 V or taken from the motor supply voltage by way of a series resistor and an integrated Z-diode. The device can be driven directly by a microprocessor with the possibility of all modes from full step through half step to mini step.

Semiconductor Group 3 1998-02-01 Figure 1 Pin Configuration (top view) TCA 3727 TCA 3727 G IEP00696 Phase 2 Inhibit GND GND Q21Q11 GND GND OSC 10 11 Q22 9 12 8 13 7 14 6 15 5 16 4 17 3 18 2 19 1 20 12 RR V S Q12 VL I Phase 1 I I I Q12 Q22 Q21 GND GND OSC Phase 1 Phase 2 I IEP00898 I GND Q11 VS++ LV Inhibit I 20I GND 241 232 223 214 205 196 187 178 169 1510 1411 1312 GND GNDGND GND

Semiconductor Group 4 1998-02-01 Pin Definitions and Functions Pin No. Function 1, 2, 19, 20 (1, 2, 23, 24) 1) Digital control inputs IX0, IX1 for the magnitude of the current of the particular phase. 3 Input Phase 1; controls the current through phase winding 1. On H-potential the phase current flows from Q11 to Q12, on L-potential in the reverse direction. 5, 6, 15, 16 (5, 6, 7, 8, 17, 18, 19, 20) 1) Ground ; all pins are connected internally. 4 Oscillator; works at approx. 25 kHz if this pin is wired to ground across 2.2 nF. 8 (10) 1) Resistor R1 for sensing the current in phase 1. 7, 10 (9, 12) 1) Push-pull outputs Q11, Q12 for phase 1 with integrated free-wheeling diodes. 9 (11) 1) Supply voltage; block to ground, as close as possible to the IC, with a stable electrolytic capacitor of at least 10 mF in parallel with a ceramic capacitor of 220 nF. 12 (14) 1) Logic supply voltage; either supply with 5 V or connect to + VS across a series resistor. A Z-diode of approx. 7 V is integrated. In both cases block to ground directly on the IC with a stable electrolytic capacitor of 10 mF in parallel with a ceramic capacitor of 100 nF. 11, 14 (13, 16) 1) Push-pull outputs Q22, Q21 for phase 2 with integrated free wheeling diodes. 13 (15) 1) Resistor R2 for sensing the current in phase 2. IX1 IX0 Phase Current Example of Motor Status H H 0 No current H L 1/3 Imax Hold LH 2/3 Imax Set LL Imax Accelerate typical Imax with Rsense = 1 W : 750 mA

Semiconductor Group 5 1998-02-01 1) TCA 3727 G only 17 (21) 1) Inhibit input; the IC can be put on standby by low potential on this pin. This reduces the current consumption substantially. 18 (22) 1) Input phase 2; controls the current flow through phase winding 2. On H-potential the phase current flows from Q21 to Q22, on L potential in the reverse direction. Pin Definitions and Functions (cont’d) Pin No. Function

Semiconductor Group 6 1998-02-01 Figure 2 Block Diagram TCA 3727 IEB00697 12 9 Q11 Q12 OSC Function Logic VLS V+ I GND Phase 1 Phase 1 Phase 1 5, 6, 15, 16 Phase 2 Phase 2 Phase 2 Logic Function Inhibit Q22 Q21 Inhibit 11I 20I 21I

Semiconductor Group 7 1998-02-01 Figure 3 Block Diagram TCA 3727 G IEB00899 D14D13 D12D11 T14 T12 T13 T11 14 11 Q11 Q12 R 1 Oscillator Functional Logic VLS V+ I GND Phase 1 Phase 1 Phase 1 5-8, 17-19 Phase 2 Phase 2 Phase 2 Logic Functional Inhibit Q22 Q21 T21 T23 T22 T24 D21 D22 D23 D24 Inhibit I I20 I21

Semiconductor Group 8 1998-02-01 Absolute Maximum Ratings TA = – 40 to 125°C Parameter Symbol Limit Values Unit Remarks min. max. Supply voltage VS 05 2 V – Logic supply voltage VL 0 6.5 V Z-diode Z-current of VL IL –5 0 m A – Output current IQ – 1 1 A – Ground current IGND – 2 2 A – Logic inputs VIxx – 6 VL + 0.3 V IXX ; Phase 1, 2; Inhibit R1 , R2, oscillator input voltageVRX, VOSC – 0.3 VL + 0.3 V – Junction temperature Tj Tj 125 150 max. 1,000 h Storage temperature Tstg – 50 125 °C–

Semiconductor Group 9 1998-02-01 Operating Range Parameter Symbol Limit Values Unit Remarks min. max. Supply voltage VS 55 0 V – Logic supply voltage VL 4.5 6.5 V without series resistor Case temperature TC – 40 110 °C measured on pin 5 Pdiss = 2 W Output current IQ – 1000 1000 mA – Logic inputs VIXX – 5 VL V IXX ; Phase 1, 2; Inhibit Thermal Resistances Junction ambient Junction ambient (soldered on a 35mm thick 20 cm2 PC board copper area) Junction case Junction ambient Junction ambient (soldered on a 35mm thick 20 cm2 PC board copper area) Junction case Rth ja Rth ja Rth jc Rth ja Rth ja Rth jc K/W K/W K/W K/W K/W K/W P-DIP-20-3 P-DIP-20-3 measured on pin 5 P-DIP-20-3 P-DSO-24-3 P-DSO-24-3 measured on pin 5 P-DSO-24-3

Semiconductor Group 10 1998-02-01 Characteristics VS = 40 V; VL = 5 V; – 25°C £ Tj £ 125°C Parameter Symbol Limit Values Unit Test Condition min. typ. max. Current Consumption from + VS from + VS from + VL from + VL IS IS IL IL 0.2 1.7 0.5 mA mA mA mA Vinh = L Vinh = H IQ1/2 = 0, IXX = L Vinh = L Vinh = H IQ1/2 = 0, IXX = L Oscillator Output charging current Charging threshold Discharging threshold Frequency IOSC VOSCL VOSCH fOSC 110 1.3 2.3 mA V V kHz C OSC = 2.2 nF Phase Current Selection (R 1; R 2) Current Limit Threshold No current Hold Setpoint Accelerate Vsense n Vsense h Vsense s Vsense a 200 460 740 250 540 825 300 620 910 mV mV mV mV IX0 = H; IX1 = H IX0 = L; IX1 = H IX0 = H; IX1 = L IX0 = L; IX1 = L Logic Inputs IX1 ; IX0 ; Phase x) Threshold L-input current L-input current H-input current VI IIL IIL IIH 1.4 (Hfi L) – 10 – 100 2.3 (Lfi H) V mA mA mA VI = 1.4 V VI = 0 V VI = 5 V

Semiconductor Group 11 1998-02-01 Standby Cutout (inhibit) Threshold Threshold Hysteresis VInh (Lfi H) VInh (Hfi L) VInhhy 1.7 0.3 2.3 0.7 2.9 1.1 V V V Internal Z-Diode Z-voltage VLZ 6.5 7.4 8.2 V IL = 50 mA Power Outputs Diode Transistor Sink Pair (D13, T13; D14, T14; D23, T23; D24, T24) Saturation voltage Saturation voltage Reverse current Forward voltage Forward voltage Vsatl Vsatl IRl VFl VFl 0.3 0.5 0.9 0.6 300 1.3 1.4 V V mA V V IQ = – 0.5 A IQ = – 0.75 A VQ = 40 V IQ = 0.5 A IQ = 0.75 A Diode Transistor Source Pair (D11, T11; D12, T12; D21, T21; D22, T22) Saturation voltage Saturation voltage Saturation voltage Saturation voltage Reverse current Forward voltage Forward voltage Diode leakage current VsatuC VsatuD VsatuC VsatuD IRu VFu VFu ISL 0.9 0.3 1.1 0.5 1.1 1.2 0.7 1.4 300 1.3 1.4 V V V V mA V V mA IQ = 0.5 A; charge IQ = 0.5 A; discharge IQ = 0.75 A; charge IQ = 0.75 A; discharge VQ = 0 V IQ = – 0.5 A IQ = – 0.75 A IF = – 0.75 A Characteristics (cont’d) VS = 40 V; VL = 5 V; – 25°C £ Tj £ 125°C Parameter Symbol Limit Values Unit Test Condition min. typ. max.

Semiconductor Group 12 1998-02-01 Quiescent Current IS, IL versus Supply Voltage V S Output Current IQX versus Junction Temperature Tj Quiescent Current IS, IL versus Junction Temperature Tj Operating Condition: VL = 5 V VInh = H C OSC = 2.2 nF Rsense = 1 W Load: L = 10 mH R = 2.4 W fphase = 50 Hz mode: fullstep 01 0 2 0 3 0V 5 0 mA IXX = H = LXXI jT = 25 C SI LI LI IED01655 V S IS , LI -25 0 25 50 75 100 C 150 jT QXI IED01657 200 800 400 600 mA -25 0 25 50 75 100 150 C IED01656 XXI = H = LIXX = 40V LI LI IS jT IIS , L mA V S

Semiconductor Group 13 1998-02-01 Output Saturation Voltages V sat versus Output Current IQ Typical Power Dissipation Ptot versus Output Current IQ (Non Stepping) Forward Current IF of Free-Wheeling Diodes versus Forward Voltages V F Permissible Power Dissipation Ptot versus Case Temperature TC 0.5 0.2 0.4 0.6 1.0 V 1.5 V F IF 0.8 A T j 1.0 = 25 C FlVV Fu IED01167 P-DSO-24 P-DIP-20 Measured at pin 5. IED01660 W totP 100-25 0 50 25 75 C 175 T c 125

Semiconductor Group 14 1998-02-01 Input Characteristics of Ixx, Phase X, Inhibit Oscillator Frequency fOSC versus Junction Temperature Tj Input Current of Inhibit versus JunctionTemperature Tj V L = 5V -6 -5 -2 3.9 2 6 IED01661 0.8 0.4 0.4 mA IXXI 0.8 V V IXX 0.2 0.6 0.6 0.2 kHz -25 0 25 50 75 100 125 C 150 V S LV OSZC = 40V = 5V = 2.2nF OSCf jT IED01663

Semiconductor Group 16 1998-02-01 Figure 6 Full-Step Operation t IED01666 Accelerate Mode Normal Mode acc set L H L H L H I Phase 1 i i I I10 seti iacc iset iacc i Q2I acc seti I21 20I H H L L L H Phase 2 t t t t t t t

Semiconductor Group 17 1998-02-01 Figure 7 Half-Step Operation t t t t t t IED01667 t Accelerate Mode Normal Mode t 21I Phase 2 I L L H H H L Q2I iset acci i set acc i acci Q1I Phase 1 seti seti L acci H I11 I H H L L

Semiconductor Group 18 1998-02-01 Figure 8 Quarter-Step Operation

Semiconductor Group 19 1998-02-01 Figure 9 Mini-Step Operation H L H L H L iset ihold I10 I11 Phase 1 IQ1 t IED01665 acci seti ihold acci i acc set i set hold acc hold i i i i IQ2 L H H L L H I I20 Phase 2 t t t t t t t

Semiconductor Group 20 1998-02-01 Figure 10 Current Control OscV IGND V Q12 V S+ S+ V V+ S + V S t t V FU sat 1V satu DV satu CV phase x phase x Operating conditions: V R L S = 40 V = 10 mH = 20 IED01177 W 2.4 V 1.4 V t t V Q11 V Q22 V Q21 t t T V L = 5 V Inhibit xx V V V phase x = H = L = H

Semiconductor Group 21 1998-02-01 Figure 11 Phase Reversal and Inhibit Inhibit Oscillator High Imped. Oscillator High Imped. Phase 1 Phase Changeover High Impedance High Impedance High Impe- dance Slow Current Decay Fast Current Decay IED01178 IGND V Osc 2.3 V 1.3 V L L IN t V Q11 satlV FuV Vsatu C satu DV FlV SV+ Phase 1I Fast Current Decay by InhibitSlow Current Decay Operating Conditions: V S = 40 V V = 5 VI phase 1L phase 1R I1X = 20 = L; V+ S Q12V = 10 mH W 1XI = H t t t t t t

Semiconductor Group 22 1998-02-01 Calculation of Power Dissipation The total power dissipation Ptot is made up of saturation losses Psat (transistor saturation voltage and diode forward voltages), quiescent losses Pq (quiescent current times supply voltage) and switching losses Ps (turn-ON / turn-OFF operations). The following equations give the power dissipation for chopper operation without phase reversal. This is the worst case, because full current flows for the entire time and switching losses occur in addition. Ptot = 2· Psat + Pq + 2· Ps where Psat @ IN { Vsatl· d + VFu (1 – d ) + VsatuC · d + VsatuD (1 – d ) } Pq = Iq · VS + IL · VL IN = nominal current (mean value) Iq = quiescent current iD = reverse current during turn-on delay iR = peak reverse current tp = conducting time of chopper transistor tON = turn-ON time tOFF = turn-OFF time tDON = turn-ON delay tDOFF = turn-OFFdelay T = cycle duration d = duty cycle tp/T Vsatl = saturation voltage of sink transistor (T3, T4) VsatuC = saturation voltage of source transistor (T1, T2) during charge cycle VsatuD = saturation voltage of source transistor (T1, T2) during discharge cycle VFu = forward voltage of free-wheeling diode (D1, D2) VS = supply voltage VL = logic supply voltage IL = current from logic supply P S V S iD tDON· iD iR+ tON· IN 2-----tDOFF tOFF+++ îþ íý ìü@

Semiconductor Group 24 1998-02-01 Application Hints The TCA 3727 is intended to drive both phases of a stepper motor. Special care has been taken to provide high efficiency, robustness and to minimize external components. Power Supply The TCA 3727 will work with supply voltages ranging from 5 V to 50 V at pin Vs. As the circuit operates with chopper regulation of the current, interference generation problems can arise in some applications. Therefore the power supply should be decoupled by a 0.22mF ceramic capacitor located near the package. Unstabilized supplies may even afford higher capacities. Current Sensing The current in the windings of the stepper motor is sensed by the voltage drop across R1 and R2. Depending on the selected current internal comparators will turn off the sink transistor as soon as the voltage drop reaches certain thresholds (typical 0 V, 0.25 V, 0.5 V and 0.75 V); (R1 , R2 =1 W ). These thresholds are neither affected by variations of VL nor by variations of VS. Due to chopper control fast current rises (up to 10 A/ms) will occure at the sensing resistors R1 and R2. To prevent malfunction of the current sensing mechanism R1 and R2 should be pure ohmic. The resistors should be wired to GND as directly as possible. Capacitive loads such as long cables (with high wire to wire capacity) to the motor should be avoided for the same reason. Synchronizing Several Choppers In some applications synchrone chopping of several stepper motor drivers may be desireable to reduce acoustic interference. This can be done by forcing the oscillator of the TCA 3727 by a pulse generator overdriving the oscillator loading currents (approximately Š– 100 mA). In these applications low level should be between 0 V and 1 V while high level should be between 2.6 V and VL. Optimizing Noise Immunity Unused inputs should always be wired to proper voltage levels in order to obtain highest possible noise immunity. To prevent crossconduction of the output stages the TCA 3727 uses a special break before make timing of the power transistors. This timing circuit can be triggered by short glitches (some hundred nanoseconds) at the Phase inputs causing the output stage to become high resistive during some microseconds. This will lead to a fast current decay during that time. To achieve maximum current accuracy such glitches at the Phase inputs should be avoided by proper control signals.

Semiconductor Group 25 1998-02-01 Thermal Shut Down To protect the circuit against thermal destruction, thermal shut down has been implemented. To provide a warning in critical applications, the current of the sensing element is wired to input Inhibit. Before thermal shut down occures Inhibit will start to pull down by some hundred microamperes. This current can be sensed to build a temperature prealarm.

Semiconductor Group 26 1998-02-01 Package Outlines P-DSO-24-3 (Plastic Dual Small Outline Package) 15.6-0.4 24 13 11 2 Index Marking 1.27 2)0.35+0.15 0.2 24x -0.2 2.65 max 0.1 0.2-0.1 2.45 -0.27.6 0.35 x 45˚ 8˚ max0.23 +0.09 10.3±0.3 0.4+0.8 1) Does not include plastic or metal protrusions of 0.15 max rer side 2) Does not include dambar protrusion of 0.05 max per side GPS05144 Sorts of Packing Package outlines for tubes, trays etc. are contained in our Data Book “Package Information”. Dimensions in mmSMD = Surface Mounted Device

Semiconductor Group 27 1998-02-01 Sorts of Packing Package outlines for tubes, trays etc. are contained in our Data Book “Package Information”. Dimensions in mm P-DIP-20-6 (Plastic Dual In-line Package) GPD05587