Data Sheet

TB67S279FTG
2017-09-15
21
Electrical characteristics 2 (Ta = 25°C and VM = 24 V, unless otherwise specified)
Characteristics
Symbol
Test condition
Min
Typ.
Max
Unit
VREF input current
IREF
VREF=2.0 V
—
0
1
μ
A
VCC voltage VCC ICC=5.0 mA 4.75 5.0 5.25 V
VCC current
ICC
VCC=5.0 V
—
2.5
5.0
mA
VREF gain
VREF (gain)
VREF=2.0 V
—
0.556
—
A/V
Thermal shutdown (TSD) threshold (Note1)
T
j
TSD
—
145
160
175
°C
VM power-on-reset threshold
VMPOR (H)
POR release 6.5 7.5 8.5 V
VMPOR (L)
POR detect
6.0
7.0
8.0
V
Over current detection (ISD) threshold
(Not2)
ISD — 2.2 3.3 4.5 A
Note 1: Thermal shutdown (TSD)
When the IC detects an over temperature, the internal circuit turns off the output MOSFETs. It has a dead band time to
avoid TSD misdetection, which may be triggered by external noise. Reassert the VM power supply or use the standby mode
by DMODE pin to release this function. The TSD is triggered when the device is over heated irregularly. Make sure not to
use the TSD function aggressively.
Note 2: Over current detection (ISD)
When the IC detects an over current, the internal circuits turns off the output MOSFETs. It has a dead band time to avoid
ISD misdetection, which may be triggered by external noise. Reassert the VM power supply or use the standby mode by
DMODE pin to release this function. The ISD is triggered when the motor current is over rated irregularly. Make sure not to
use the ISD function aggressively.
Back-EMF
While a motor is rotating, there is a timing at which power is fed back to the power supply. At that timing, the motor current
recirculates back to the power supply due to the effect of the motor back-EMF.
If the power supply does not have enough sink capability, the power supply and output pins of the device might rise above
the rated voltages. The magnitude of the motor back-EMF varies with usage conditions and motor characteristics. It must be
fully verified that there is no risk that the TB67S279FTG or other components will be damaged or fail due to the motor
back-EMF.
Cautions on Overcurrent Shutdown (ISD) and Thermal Shutdown (TSD)
The ISD and TSD circuits are only intended to provide temporary protection against irregular conditions such as an output
short-circuit; they do not necessarily guarantee the complete IC safety.
If the device is used beyond the specified operating ranges, these circuits may not operate properly: then the device may be
damaged due to an output short-circuit.
The ISD circuit is only intended to provide a temporary protection against an output short-circuit. If such a condition persists
for a long time, the device may be damaged due to overstress. Overcurrent conditions must be removed immediately by
external hardware.
IC Mounting
Do not insert devices incorrectly or in the wrong orientation. Otherwise, it may cause breakdown, damage and/or
deterioration of the device.