Test Procedure for the LV8729VGEVB Evaluation Board CURRENT PROBE AMPLIFIER 1 Osclloscope CURRENT PROBE AMPLIFIER 2 PROBE INPUT PROBE INPUT OUTPUT OUTPUT CHANNEL 1 2 3 4 Stepping Motor Power supply 2 A V - + Power supply 3 A V Power supply 1 A V - - + + Function generator Hz CHANNEL 1 2 Table1: Required Equipment Equipment Power supply1 Power supply2 Power supply3 Function generator Oscilloscope Current probe1 Current probe2 LV8729V Evaluation Board Stepper Motor 1/8/2014 1 Efficiency 35V-5A 5V-0.5A 10V-1A 200kHz 4 channel 35V-3A www.onsemi.com Test Procedure: 1. Connect the test setup as shown above. 2. Set it according to the following specifications. Supply Voltage • • • VM (9 to 32V): Power Supply for LSI VREF (0 to 3V): Const. Current Control for Reference Voltage VDD (2 to 5V): Logic “High” voltage for toggle switch Toggle Switch State • • • Upper Side: High (VDD) Middle: Open, enable to external logic input Lower Side: Low (GND) Operations Guide 1. Initial Condition Setting: Set “Open” the toggle switch STEP, and “Open or Low” the other switches. 2. Power Supply: Supply DC voltage to VM, VREF and VDD. 3. Ready for Operation from Standby State: Turn “High” the ST , OE and RST terminal toggle switch. Channel 1 and 2 are into Full step excitement initial position (100%, -100%) . 4. Motor Operation: Input the clock signal into the terminal STEP. 5. Other Setting: (See Application Note for detail) i. FR: Motor rotation direction (CW / CCW) setting. ii. MD1 , MD2 , MD3: Excitation mode. Setting for External Component Value 1. Constant Current (100%) At VREF = 1.0V Iout = VREF [V]/5/RNF [ohm] =1.0 [V] / 5 / 0.47 [ohm] =0.426 [A] 2. Chopping Frequency Fchop =Ichop [uA]/(Cchop x Vt x 2) =10 [uA] / (180 [pF] x 0.5 [V] x 2) =55 [kHz] 3. Check the STEP and MO terminal voltage at scope CH1 and CH2, and the output current waveform at scope CH3 and CH4. 1/8/2014 2 www.onsemi.com Table2: Desired Results INPUT VM=24V VREF=1.5V VDD=5V ST=High OE=High RST=High FR=Low OUTPUT * Refer to the following waveform ●Figure 1. Full Step MD1=L , MD2=L , MD3=L STEP=300Hz (Duty 50%) 2ms/div ●Figure 2. Half Step MD1=H , MD2=L , MD3=L STEP=300Hz (Duty 50%) ch1 STEP 5V/div ch2 MONI 5V/div 5ms/div STEP 5V/div ch1 MONI 5V/div ch2 ch3 ch3 Iout1 1A/div Iout1 1A/div ch4 Iout2 1A/div ●Figure 3. 1/16 Step MD1=L , MD2=L , MD3=H STEP=300Hz (Duty 50%) 50ms/div Iout2 1A/div ch4 ●Figure 4. 1/128 Step MD1=H , MD2=H , MD3=H STEP=1500Hz (Duty 50%) 50ms/div ch1 STEP 5V/div ch1 STEP 5V/div ch2 MONI 5V/div ch2 MONI 5V/div ch3 ch3 Iout1 1A/div Iout1 1A/div Iout2 1A/div ch4 MD3 Low Low Low Low High High High High 1/8/2014 Input MD2 Low Low High High Low Low High High MD1 Low High Low High Low High Low High Iout2 1A/div ch4 Excitation setting method Initial position Micro step Excitation resolution mode 1ch current 2ch current Full Step 2-phase 100% -100% Half Step 1-2 phase 100% 0% Quarter Step W1-2 phase 100% 0% 1/8 Step 2W1-2 phase 100% 0% 1/16 Step 4W1-2 phase 100% 0% 1/32 Step 8W1-2 phase 100% 0% 1/64 Step 16W1-2 phase 100% 0% 1/128 Step 32W1-2 phase 100% 0% 3 www.onsemi.com