tda5144t NXP Semiconductors, tda5144t Datasheet - Page 15

• Manufacturer Part Number: tda5144t
• Description: Brushless Dc Motor Drive Circuit
• Manufacturer: NXP Semiconductors

Philips Semiconductors
M
DC motors can be controlled in an analog manner using
the OTA.
For the analog control an external transistor is required.
The OTA can supply the base current for this transistor
and act as a control amplifier (see Fig.8).
R
It is necessary to protect high current circuits and the
output stages are protected in two ways:
It is possible, that when braking, the motor voltage (via the
flyback diodes and the impedance on VMOT) may cause
higher currents than allowed ( 0.6 A). These currents
must be limited externally.
June 1994
ELIABILITY
OTOR
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 local temperature
becomes too high.
Brushless DC motor drive circuit
C
ONTROL
15
Product specification
TDA5144