zl30112 Zarlink Semiconductor, zl30112 Datasheet - Page 12

• Manufacturer Part Number: zl30112
• Description: Slic/codec Dpll
• Manufacturer: Zarlink Semiconductor

6.3
The ZL30112 requires that the 3.3 V is not powered after the 1.8 V. This is to prevent the risk of latch-up due to the
presence of parasitic diodes in the IO pads.
Two options are given:
1. Power-up 3.3 V first, 1.8 V later
2. Power up 3.3 V and 1.8 V simultaneously ensuring that the 3.3 V power is never lower than 1.8 V minus a few
6.4
A simple power up reset circuit with about a 60 µs reset low time is shown in Figure 8. Resistor R
only and limits current into the RST pin during power down conditions. The reset low time is not critical but should
be greater than 300 ns.
hundred millivolts (e.g., by using a schottky diode or controlled slew rate)
Power Up Sequence
Reset Circuit
ZL30112
ZL30112
The 100 Ω resistor and the 1 µH inductor may improve
stability and are optional.
Figure 7 - Crystal Oscillator Circuit
Figure 8 - Power-Up Reset Circuit
OSCi
OSCo
1 MΩ
RST
Zarlink Semiconductor Inc.
ZL30112
100 Ω
1 kΩ
R
12
P
20 MHz
10 kΩ
R
+3.3 V
1 µH
10 nF
C
P
is for protection
Data Sheet