WM8196SCDS Wolfson Microelectronics, WM8196SCDS Datasheet - Page 11

• Manufacturer Part Number: WM8196SCDS
• Description: Video ICs 16-Bit 12MSPS 3-Channel AFE
• Manufacturer: Wolfson Microelectronics
• Type: CCD/CISr

Specifications of WM8196SCDS

• Operating Supply Voltage: 3.3 V or 5 V
• Supply Current: 60 mA
• Maximum Operating Temperature: + 70 C
• Package / Case: SSOP-28
• Conversion Rate: 12000 KSPS
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Number Of Channels: 3
• Resolution: 16 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

WM8196
INTERNAL POWER ON RESET CIRCUIT
Figure 7 Typical Power up Sequence where AVDD is Powered before DVDD1
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The WM8196 includes an internal Power-On-Reset Circuit, as shown in Figure 6, which is used to
reset the digital logic into a default state after power up. The POR circuit is powered from AVDD and
monitors DVDD1. It asserts PORB low if AVDD or DVDD1 is below a minimum threshold.
The power supplies can be brought up in any order but is important that either AVDD is brought up
and is stable before DVDD comes up or vice versa as shown in Figure 7 and Figure 8.
Figure 7 shows a typical power-up sequence where AVDD is powered up first. When AVDD rises
above the minimum threshold, Vpora, there is enough voltage for the circuit to guarantee PORB is
asserted low and the chip is held in reset. In this condition, all writes to the control interface are
ignored. Now AVDD is at full supply level. Next DVDD1 rises to Vpord_on and PORB is released
high and all registers are in their default state and writes to the control interface may take place.
On power down, where AVDD falls first, PORB is asserted low whenever AVDD drops below the
minimum threshold Vpora_off.
Figure 6 Internal Power On Reset Circuit Schematic
PD Rev 4.3 March 2007
Production Data
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