datasheetbank_Logo
búsqueda de Hoja de datos y gratuito Fichas de descarga

ACT5830QJCES-T(2008) Ver la hoja de datos (PDF) - Active-Semi, Inc

Número de pieza
componentes Descripción
Lista de partido
ACT5830QJCES-T
(Rev.:2008)
ACTIVE-SEMI
Active-Semi, Inc ACTIVE-SEMI
ACT5830QJCES-T Datasheet PDF : 41 Pages
First Prev 11 12 13 14 15 16 17 18 19 20 Next Last
ACT5830
Rev PrB, 05-Mar-08
SYSTEM MANAGEMENT
FUNCTIONAL DESCRIPTIONS
The ACT5830 offers a wide array of system man-
agement functions that allow it to be configured for
optimal performance in a wide range of applica-
tions.
I²C Serial Interface
At the core of the ACT5830s flexible architecture is
an I2C interface that permits optional programming
capability to enhance overall system performance.
Use standard I2C write-byte commands to program
the ACT5830 and read-byte commands to read the
IC’s status. Figure 1: I2C Serial Bus Timing provides
a standard timing diagram for the I2C protocol. The
ACT5830 always operates as a slave device, with
address 1010101.
System Startup & Shutdown
The ACT5830 features a flexible enable architec-
ture that allows it to support a variety of push-button
enable/disable schemes. Although other startup
routines are possible, a typical startup and shut-
down process would proceed as follows (referring
to Figure 2):
System startup is initiated whenever one of the fol-
lowing conditions occurs:
1) The user presses the push-button, asserting
PWR_ON high,
2) A valid supply (>4V) is connected to the
charger input (CHG_IN), or 3) a headset is con-
nected, asserting HF_PWR high.
The ACT5830 begins its system startup procedure
by enabling REG, LDO2 and LDO3, then LDO1 are
enabled when VBUCK or VOUT2 reaches 87% of
its final value. nRST is asserted low when VOUT1
reaches 87% of its final value, holding the micro-
processor in reset for a user-selectable reset period
of 65msec. If (VBUCK or VOUT2) and VOUT1 are
within 13% of their regulation voltages when the
reset timer expires, the ACT5830 de-asserts nRST
so that the microprocessor can begin its power up
sequence. Once the power-up routine is success-
fully completed, the microprocessor asserts
PWR_HOLD high to keep the ACT5830 enabled
after the push-button is released by the user.
Once the power-up routine is completed, the re-
maining LDOs can be enabled/disabled via either
the I2C interface or the TCXO_EN (LDO4), RX_EN
(LDO5), TX_EN (LDO6), and PWR_HOLD (REG
and LDO1) pins.
This start-up procedure requires that the push-
button be held until the microprocessor assumes
control of PWR_HOLD, providing protection against
inadvertent momentary assertions of the push-
button. If desired, longer “push-and-hold” times can
be easily implemented by simply adding an addi-
tional delay before assuming control of
PWR_HOLD. If the microprocessor is unable to
complete its power-up routine successfully before
the user lets go of the push-button, the ACT5830
will automatically shut itself down.
Once a successful power-up routine is completed,
the user can initiate a shutdown process by press-
ing the push-button a second time. Upon detecting
a second assertion of PWR_ON (by depressing the
push-button), the ACT5830 asserts nON to interrupt
the microprocessor which initiates an interrupt ser-
vice routine that will reveal that the user pressed
the push-button. If HF_PWR and CHG_OK are both
low, the microprocessor then initiates a power-down
routine, the final step of which will be to de-assert
PWR_HOLD, disabling REG and LDO1.
Innovative PowerTM
ActivePMUTM is a trademark of Active-Semi.
I2CTM is a trademark of Philips Electronics.
- 11 -
www.active-semi.com
Copyright © 2008 Active-Semi, Inc.

Share Link: 

datasheetbank.com [ Privacy Policy ] [ Request Datasheet ] [ Contact Us ]