STFPC320 datasheet(15/78 Pages) STMICROELECTRONICS

部件名	STFPC320

功能描述	Front panel controller/driver with standby power management and real-time clock

PDF	78 Pages

Scroll/Zoom	100%

制造商	STMICROELECTRONICS [STMicroelectronics]

网页	http://www.st.com

标志

15 / 78 page

STFPC320

Functional description

15/78

4.3

Entering standby mode

The STFPC320 will control the power to the main board using the STBY pin. During normal

operation, the STBY pin is at a low level which externally controls a power MOS switch to

enable power to the main board. The STFPC320 asserts the STBY pin to a high when any

one of the following conditions occur:

●

Processor fails to respond by enabling the READY pin within 10 s upon first power-up

(cold boot up)

●

Guard timer counts down to 0 s

●

Processor makes the READY pin to low (can happen in various conditions, such as

user presses STBY key on front panel, STBY key on remote control, etc.)

Note:

Guard timer can be kept on during normal condition when READY is high (depending on the

user).

In this condition, the guard timer can be disabled or enabled. If the guard timer is enabled,

the timer needs to be cleared before the programmed count of the timer is reached. If the

programmed count is reached, the STBY will be asserted.

It is advisable not to enable the guard timer during normal operation.

Figure 5.

Standby mode behaviour

STFPC320 数据表(PDF) 15 Page - STMicroelectronics