wm8918 Wolfson Microelectronics plc, wm8918 Datasheet - Page 123

• Manufacturer Part Number: wm8918
• Description: Ultra Low Power Dac For Portable Audio Applications
• Manufacturer: Wolfson Microelectronics plc

Production Data
POWER-ON RESET
Figure 69 Power On Reset timing - AVDD enabled first
Figure 70 Power On Reset timing - DCVDD enabled first
w
Internal POR
DCVDD
AVDD
LO
0V
0V
HI
V
pora
POR undefined
The WM8918 includes an internal Power-On-Reset (POR) circuit, which is used to reset the digital
logic into a default state after power up. The POR circuit is powered from AVDD and monitors
DCVDD. The internal POR
thresholds.
The specific behaviour of the circuit will vary, depending on the relative timing of the supply voltages.
Typical scenarios are illustrated in Figure 69 and Figure 70.
POR active
V
pord_on
¯ ¯ ¯
signal is asserted low when AVDD or DCVDD are below minimum
Device ready
POR active
PD, Rev 4.0, September 2010
V
pora_off
WM8918
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