Motorola 8900 - Blackberry Curve Cell Phone OEM Car Charger, Руководство разработчика

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Chapter 2: Hardware Interface Description
December 15, 2008 C24 Module Hardware Description 41
Important:
The VREF regulator is powered from the C24's main power supply, and therefore
any current sourced through this regulator originates from the C24 VCC supply. The
overall VCC current consumed by C24 is directly affected by the VREF operation.
The C24 current consumption rises with respect to the current sourced through
VREF.
Figure 2-23 shows the VREF power-up timing.
Figure 2-23: VREF Power-up Timing
Table 2-20 gives the VREF specifications.
Wakeup Out
Some applications incorporate their own power saving mode, in which they operate with minimal
functionality, including disabling of interfaces and serial communications.
The wakeup-out (WKUPO_N) signal is an active low output, which is designed to support a low
power mode feature in the host application. This signal is used by C24 to indicate that it requires
to communicate with the host application through the serial interface, due to an incoming call or
data, or an unsolicited event. Applications that incorporate a low power mode should use this
Table 2-20: VREF Specifications
Parameter Conditions Min Typ Max Unit
V
OUT
I
OUT
< 150 mA -4% 2.8 +4% V
I
OUT
150 mA
Load regula-
tion 0.65 mV/
mA
Line regula-
tion 2.8 mV
PSRR 20 Hz - 20 kHz 21 dB