TB6613FTG Toshiba, TB6613FTG Datasheet - Page 7

• Manufacturer Part Number: TB6613FTG
• Manufacturer: Toshiba

Specifications of TB6613FTG

• Function: Driver
• Vopmax (vm*): 5.5V (6V)
• Io (lpeak): 0.6A (0.8A)
• Channel: 8-ch
• I/f: serial input
• Option: 6bit u-Step STM drive x2
• Package: VQON44
• Rohs Compatible†: yes

Constant-Current H-Bridge Drivers: PWM Constant-Current Choppers with a
Constant Turn-Off Period
generated by dividing the external MCK signal. The turn-off period can be adjusted by changing either the MCK
frequency or the number of its rising edges counted (2, 4, 6 or 8 counts).
Example: Turn-off period of four clock cycles
is sensed via an external current-sensing resistor. As the current increases, a voltage (VRF) develops across the
resistor, which is fed back to the internal comparator. At the predetermined reference voltage (Vlimit), the
comparator turns off (chops) the power supply.
internal clock signal as a turn-off period. (The counter resets at the fifth rising edge of the clock.)
transistors.
The TB6613FTG has PWM choppers with a constant turn-off period.
The turn-off period is measured by counting the number of rising edges of an internal clock signal, which is
Turning on the power supply causes a current to flow into the motor coils. The peak current through the winding
When high-side output transistors are turned off, the TB6613FTG, by default, counts four rising edges of the
Based on this turn-off period, the TB6613FTG generates a PWM signal that turns on and off the output
Generated PWM
Internal clock
(The upper limit of the coil current (IO peak) can be calculated as: IO = Vlimit/RNF.)
Coil current
(counter)
Off timer
signal
Vlimit
VRF
Power on
1 2 3
Timing Diagram of the PWM Constant-Current Chopper Circuit
4 5 6
with a Turn-Off Period of Four Clock Cycles
on
7
decay
on
Counts 4 rising edges of internal clock.
decay
on
decay
TB6613FTG
2008-06-27
Power off
on