mc145170-2 Freescale Semiconductor, Inc, mc145170-2 Datasheet - Page 14

• Manufacturer Part Number: mc145170-2
• Description: Pll Frequency Synthesizer With Serial Interface
• Manufacturer: Freescale Semiconductor, Inc

Pin Connections
3.5
V
Most Positive Supply Potential (Pin 16)
This pin may range from 2.7 to 5.5 V with respect to V
For optimum performance, V
very close to the device. Lead lengths on the capacitor(s) should be minimized. (The very fast switching
speed of the device causes current spikes on the power leads.)
V
Most Negative Supply Potential (Pin 12)
This pin is usually ground. For measurement purposes, the V
NOTES: This initialization sequence is usually not necessary because the on-chip power-on reset circuit performs the
14
DD
SS
ENB
initialization function. However, this initialization sequence must be used immediately after power up if control of the CLK
pin is not possible. That is, if CLK (Pin 7) toggles or floats upon power up, use the above sequence to reset the device.
Also, use this sequence if power is momentarily interrupted such that the supply voltage to the device is reduced to
below 2.7 V, but not down to at least 1 V (for example, the supply drops down to 2 V). This is necessary because the
on-chip power-on reset is only activated when the supply ramps up from a voltage below approximately 1.0 V.
CLK
D
in
Power Supply
Power Up
4 or More Clocks
1
2
Don't Cares
DD
3
should be bypassed to V
MC145170-2 Technical Data, Rev. 5
Figure 15. Reset Sequence
1
Zeroes
SS
2
.
SS
using low-inductance capacitor(s) mounted
3
SS
One
pin is tied to a ground plane.
4
Zero
5
Don't Cares
Freescale Semiconductor