upd16858b Renesas Electronics Corporation., upd16858b Datasheet - Page 8

• Manufacturer Part Number: upd16858b
• Description: Three-phase Spindle Motor Driver For Monolithic Cd-rom
• Manufacturer: Renesas Electronics Corporation.

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(4) Standby mode
The power supplied to the internal circuitry of the IC can be turned off by setting the IC in the standby mode.
In the standby mode, each pin goes into a high-impedance state (H bridge all OFF). The internal oscillation
block also stops and therefore, the circuit current can be decreased.
If the motor driver is stopped by using the standby pin while the driver is operating, the motor is stopped by
force of inertia. It takes the motor driver about several 10 s to start when it is set in the normal operation
mode.
Caution Output current
The rated output current differs depending on whether the motor revolves at a constant
speed (steady state), is started (steady state), or reversed and brake is applied. The rated
DC current when the motor revolves at a constant speed is 0.5 A, and the rated instantaneous
current when the motor is started is 1.3 A. When brake is applied to stop the motor and when
the motor is reversed, the maximum current is 1.5 A.
When a brake is applied or the motor is reversed, a current exceeding that when the motor
revolves at a constant speed (immediately before a brake is applied) instantaneously flows
because of the counter electromotive force due to the motor inductance. Determine the value
of overcurrent for the steady state, taking the peak current for reversing or applying a brake
to the motor into consideration.
STB Pin
Data Sheet S13480EJ3V0DS00
H
L
Normal mode
Standby mode
Operation Mode
PD16858B/C