Deleted Figure 18; Renumbered Sequentially; Changes To Rising Edge Triggered Wake-Up Mode Section; Power Requirements; Internal Power, V - Analog Devices AD5100 Manual

POWER REQUIREMENTS

INTERNAL POWER, V

REG

The AD5100 internal power, V
becomes active when V
2MON
AD5100 on and off with a different behavior depending on the
V monitoring mode selection.
2MON
By default, the AD5100 turns on when the voltage at V
above the logic threshold, V
2MON_ON
logic threshold, V , AD5100 turns off 2 seconds after
2MON_OFF
SHDN is deasserted. Note that AD5100 requires 5 μs to start up
and that V must be applied before V
1MON
AD5100 turn-off allows the system to complete any housekeeping
tasks before the system is powered off.
default V and V waveforms.
2MON REG
V
2MON_ON*
V
2MON
V
2MON,IH
SHDN
V
REG
NOTES
1. 6V < V
1MON
2. * = PROGRAMMABLE
, is derived from V
REG 1MON
reaches 2.2 V. V is used to turn
2MON
2MON
. When V falls below the
2MON
. Extension of the
2MON
shows the
Figure 18
t
GLITCH
V
2MON_OFF*
t
2SD_HOLD*
t
VREG_ON_DELAY
< 30V
Figure 18. Internal Power V
Rising Edge Triggered Wake-Up Mode
If rising edge triggered wake-up V
and
the AD5100 does not turn off when V
To configure the part into rising edge triggered mode, set the
V off threshold register, Register 0x04[3:1], to 1001.
2MON
In this mode, once the part is powered on, it can only be powered
rises
down by an I
supply on the V
bus while in rising edge triggered mode, the user must first
ensure that the software power down feature is enabled.
•
Register 0x18[3] = 0: enable software power-down feature
•
Register 0x18[3] =1: disable software power-down feature
The user must then write to Register 0x17[0], to actually power
down the AD5100.
•
Register 0x17[0] = 0: AD5100 not in software power-down
•
Register 0x17[0] = 1: power down AD5100
This feature is for applications that use a wake-up signal.
V
2MON_ON*
V
2MON_OFF*
t t
2SD_DELAY* 2SD_HOLD*
t
2SD_DELAY*
vs. V Timing Diagrams (Default)
REG 2MON
Rev. A | Page 21 of 36
mode is selected instead,
2MON
2MON
2
C power-down instruction or by removing the
pin. To power down the part over the I
1MON
t
2SD_DELAY*
t
VREG_OFF_DELAY
t
VREG_OFF_DELAY
AD5100
returns to a logic low.
2
C