TB6549F/FG/P/PG/HQ

2007-3-6

10

6.

circuit.

• The operating voltage range is shown below:

• This IC has a power monitoring function for preventing an output malfunction on power-up. However,

Toshiba recommends that IN1, IN2, and SB be set to the Low level at power-on.

7.

GND Sections

• This IC includes two separate GND sections: S-GND for controlling and P-GND for outputting. Be sure

to short-circuit these two GNDs as close to TB6549 as possible.

8.

Power Monitoring Circuit

(design target value) after this circuit starts operating.

9.

This IC includes a thermal shutdown circuit, which turns the output OFF when the junction temperature

(Tj) exceeds 160°C (typ.). The output turns back ON automatically. The thermal hysteresis is 20°C.

This IC includes a circuit to detect current flowing through the output power transistors. The current limit

is set to 5 A (typ.). The circuit detects a current flowing through each of the four output power transistors.

If the current in any one output power transistor exceeds the set limit, this circuit turns all the outputs

OFF.

This circuit includes a timer that causes the outputs to be OFF for 50

μs (typ.) after detection of an

overcurrent and then turn back ON automatically. If the overcurrent continues to flow, this ON-OFF

operation is repeated. Note that to prevent a malfunction due to a glitch, an insensitive period of 10

μs

(typ.) is provided.

The set limit is 5 A (typ.) as a design target value. The distributions shown below exist because of the

variations in thermal characteristics of different ICs. These distributions should be fully considered in the

motor torque design.

Also, output peak current should be less than 3 A because of the variations below,

Detected current: Approximately from 3.5 to 6.5 A

50

μs

(typ.)

0

10

μs

(typ.)

Insensitive period

50

μs

(typ.)

10

μs

(typ.)

Output Current