ta8429h TOSHIBA Semiconductor CORPORATION, ta8429h Datasheet - Page 4

• Manufacturer Part Number: ta8429h
• Description: Full-bridge Driver H-switch For Dc Motor
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Over-current Protection
● Basic operation
● Explanation of the operation
current, the input signal controls the output. If the output current exceeds the detection current, it changes
to a switching waveform shown in Figure 1.
connected to each output transistor and to a short-circuit prevention circuit. If a current higher than the ISD
detection current flows through one of the four output transistors, the short-circuit prevention circuit starts
operating. This circuit incorporates a timer. If the over-current mode lasts for 20 µs (typically), the output is
switched to the high-impedance state. It returns to the ON mode in 80 µs (typically). If the IC is still in the
over current mode, the switching mode stated above is repeated until the IC is released from the
over-current mode.
ground, the IC may break down before the protection circuit starts operating. Therefore use a resistor or fuse
in the supply voltage (V
When the output current (pin 4 or 8, that is, I
The output current is detected by monitoring the VBE of each output transistor. A detector element is
This circuit cannot limit all types of over current. If the outputs are short-circuited to each other or to a
Detection current of 5 A
(typically)
S
) line.
(ISD)
Figure 1 Basic operation
sink
4
or I
source
) is equal to or lower than the ISD detection
TA8429H/HQ
2006-3-2