TDA5145TS Datasheet, PDF (14/20 Pages) NXP Semiconductors – Brushless DC motor drive circuit

Philips Semiconductors
Brushless DC motor drive circuit
Product specification
TDA5145TS
Table 3 Switching sequence after a reset pulse; note 1
DIR
RESET
MOT1
MOT2
H
H
Z
L
H
L
Z
L
H
L
H
L
H
L
H
Z
H
L
Z
H
H
L
L
H
H
L
L
Z
L
H
H
L
L
L
H
L
L
L
Z
L
L
L
L
Z
L
L
L
H
L
L
Z
H
L
L
H
Z
Note
1. Z = high-impedance OFF-state; L = LOW state; H = HIGH state.
DIR
FUNCTION
H
reset
H
normal direction
Z
mode sequence
L
L
Z
H
Z
reset
Z
reverse direction
H
mode sequence
H
Z
L
L
Table 4 Priority of function; note 1
BRAKE
L
L
L
L
H
H
H
H
Note
1. L = LOW state; H = HIGH state.
TEST
L
L
H
H
L
L
H
H
RESET
L
H
L
H
L
H
L
H
FUNCTION
normal
reset
test
test
brake
brake
brake
brake
RELIABILITY
It is necessary to protect high current circuits and the output stages are protected in two ways:
• Current limiting of the ‘lower’ output transistors. The ‘upper’ output transistors use the same base current as the
conducting ‘lower’ transistor (+15%). This means that the current to and from the output stages is limited.
• Thermal protection of the six output transistors is achieved by each transistor having a thermal sensor that is active
when the transistor is switched on. The transistors are switched off when the ambient temperature becomes too high.
1998 Oct 27
14