PBL3717 ERICSSON | Alldatasheet
Document overview
- Manufacturer or author: Provided By alldatasheet.com(free datasheet download site)
- PDF pages: 7
Technical content
PBL 3717 is a bipolar monolithic citcuit intended to control and drive the current in one” Hal-step and full-step modes. Two PBL 3717 and a small number of external components form a complete control + Wide voltage range 10 — 45 V. + Current levels can be selected in steps. + Thermal averioad protection. Figure 1. Block diagram. oo
Figure 2. Definition of symbols.
s ERICSSON 3 PBL 3717
Electrical Characteristics
Electrical characteristics over recommended operating conditions. C, = 820 pF, Ry = 56 kohm Ret, Parameter ‘Symbol fig. Conditions Min 1 Max Unit Supplycurent eg 8 25 mA Total power dissipation Py ¥, = 30 KHz, I, = 500 mA. 18 23 w T, = +25°C. Note 2, 4. f, = 30 kHz, |, = 800 mA. 37 w T= 425°C: Note 8. ee Thermal shutdown junction temperature 170 °C Tum-off delay 2 _T, = +25°C, dV /at > 50 mV/us. 09 15 us Logic inputs ee Logic HIGH input voltage Vin 3 20 Vv Logic LOW input voltage Ye 3 _ oe VO Logic HIGH input current, 3 = 0.4V ee > eee mA Logic LOW input current 8 Mae4V 20 yA Threshold voltage Vou 3 Vq=5.0V,|)=1,=LOW 390 420 440 mv Vou V,, = 5.0 V, |, = HIGH, |, = LOW 230 250 270 mv ee Vo. Va = 5.0.V, lp = LOW, |, = HIGH 65 80 90 mV. Input current - Ne 3 -20 pA _ ReferenceImput Input resistance R, T, = 725°C 68 kohm Motor Outputs Total saturation voltage drop i, = 500 mA 40 Vv Output leakage current I= = HIGH, T, = +25°C 0A Monostable Cut off time __ tor 2 Va = 10Vs 25 HS a7 _ 3 us . Thermal Characteristics Ret. Parameter Symbol fig. Conditions TP Max unit Thermal resistance A 11 °C Rih,, 14 Note 2. 40 Cw Notes 1. All voltages are with respect to ground, Currents are positive into, negative out of specified terminal 2. All ground pins soldered onto a 20 cm? PCB copper area with free air convection. T, = +25°C. 3. DIP package with extemal heatsink (Staver V7) and minimal copper area. Typical Ath, ,= 27.5°CW. 4, Not covered by final test program. 615
Figure 3. Definition of terms. Figure 4. Pin configuration zero current can be selected by the input Low level 20% LH . value of the sensing resistor timing components R, and C,. Phase input. The phase input \\n=(Vq*0.016)/ Ry IA}, at 20% level uring t,. itis ignored. phase shit. Comparators for measuring each of the a constant current through the winding. Half- and full-step operation is selectable current levels. The motor See figures 5 and 6.
permitted to short circuit the outputs. decay (see figures 6 and 7). utsep }. Figure 7. Principal operating sequence. -
s ERICSSON % PBL 3717 and circuit GND should be kept as short os as possible. This applies also to the leads | connecting R, and R,, to pin 16 and pin il em 10 respectively. ry Tea ns In order to minimize electromagnetic : Hie <2 interference, it is recommended to route 3) Geet eee aie M, and M, leads in parallel on the printed | Vee ee Woe circuit board directly to the terminal Lear ey es connector. The motor wires should be ee eee OS) lef SD | twisted in pairs, each phase separately, | | er when installing the motor system. fs chav WTR Unused inputs | we | we Unused inputs should be connected | a to proper voltage levels in order to obtain the highest possible noise immunity. Figure 13. Heatsinks, Staver, type V7 and V8 by Columbia-Staver UK. Ramping A stepper motor is a synchronous eee rom motor and does not change its speed due [ | to load variations. This means that the | ° , q b torque of the motor must be large enough t Y q LY to match the combined inertia of the | » q bg motor and load for all operation modes. At |» | \\y 6 B speed changes, the requires torque KEE i 6 increases by the square, and the required | "IN Wy i B YY, power by the cube of the speed change. . LINE 4d ot VA Ramping, ie, controlled acceleration or | CLARE qf deceleration must then be considered to eLittiiiiti avoid motor pull-out. L Bessette fn Voce Vn Figure 14. Copper foil used as a heatsink. The supply voltages, Vgc ANd Vy |< can be tured on or off in any order. Description Condon Tua Normal dv/at vaiues are assumed. ih, Junction to Case Case = the four ground pins 11°C Before a driver circuit board is ith. Junction to Ambient The four ground pins soldered to a 40°C removed from its system, all supply 20 em? ground plat cding ¥ 14. voltages must be turned off to avoid 20m? ground plane according to figurets destructive transients being generated by Table 1. Thermal resistance . Thermal resistance values are heavily dependant on the motor. location and shape of heatsink. Analog control - {As the current levels can be continu. Sensor Resistor ously controlled by modulating the V,, The R, resistor should be of a non- input, limited microstepping can be inductive type power resistor. A 1.0 ohm achieved. resistor, tolerance < 1%, is a good choice i for 420 mA max motor current at V, = SV. Switching frequency The maximum motor current, i, Can ‘The motor inductance, together with _be calculated by using the formula: the pulse time, t,,, determines the i, = (Vp * 0.084) / R, [A], at 100% level ‘switching frequency of the current regulator. The choice of motor may then in = (Va * 0.050) /R, [A], at 60% level require other values on the R, C,compo- ; _wy , . honts than those recommended in igure n= (Yn *0-016)/R [A], at 20%6 evel. 7, to obtain a switching frequency above the audible range. Switching frequencies . above 40 kHz are not recommended Ordering Information because the current regulation can be Package ‘Temp. Range Part No. affected. Plastic DIP. Oto 70°C = PBL3717N 619