Spread-Spectrum EconOscillator
DS1086
AC ELECTRICAL CHARACTERISTICS: 2-WIRE INTERFACE (continued)
(V
CC
= 5V 5%, T = 0°C to +70°C.)
A
PARAMETER
SYMBOL
CONDITION
MIN
0.6
TYP
MAX
UNITS
Fast mode
Setup Time for STOP
t
µs
SU:STO
Standard mode
4.0
Capacitive Load for Each Bus
Line
C
(Note 16)
400
10
pF
B
NV Write-Cycle Time
Input Capacitance
t
ms
pF
WR
C
5
I
Note 1:
Note 2:
All voltages are referenced to ground.
DAC and OFFSET register settings must be configured to maintain the master oscillator frequency within this range.
Correct operation of the device is not guaranteed if these limits are exceeded.
Note 3:
Note 4:
This is the absolute accuracy of the master oscillator frequency at the default settings.
This is the change that is observed in master oscillator frequency with changes in voltage from nominal voltage at
T
A
= +25°C.
Note 5:
This is the percentage frequency change from the +25°C frequency due to temperature at V
= 5V. The maximum tem-
CC
perature change varies with the master oscillator frequency setting. The minimum occurs at the default master oscillator
frequency (f ). The maximum occurs at the extremes of the master oscillator frequency range (66MHz or 133MHz)
default
(see Figure 2).
Note 6:
Note 7:
The dither deviation of the master oscillator frequency is unidirectional and lower than the undithered frequency.
The integral nonlinearity of the frequency adjust DAC is a measure of the deviation from a straight line drawn between the
two endpoints of a range. The error is in percentage of the span.
Note 8:
Note 9:
This is true when the prescaler = 1.
Frequency settles faster for small changes in value. During a change, the frequency transitions smoothly from the original
value to the new value.
Note 10: This indicates the time elapsed between power-up and the output becoming active. An on-chip delay is intentionally
introduced to allow the oscillator to stabilize. t is equivalent to approximately 512 master clock cycles and therefore
stab
depends on the programmed clock frequency.
Note 11: Output voltage swings can be impaired at high frequencies combined with high output loading.
Note 12: A fast-mode device can be used in a standard-mode system, but the requirement t > 250ns must then be met.
SU:DAT
This is automatically the case if the device does not stretch the LOW period of the SCL signal. If such a device does
stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line at least t
1000ns + 250ns = 1250ns before the SCL line is released.
+ t
=
R MAX
SU:DAT
Note 13: After this period, the first clock pulse is generated.
Note 14: A device must internally provide a hold time of at least 300ns for the SDA signal (referred to as the V
of the SCL sig-
IH MIN
nal) in order to bridge the undefined region of the falling edge of SCL.
Note 15: The maximum t
need only be met if the device does not stretch the LOW period (t
) of the SCL signal.
HD:DAT
LOW
Note 16: C —total capacitance of one bus line, timing referenced to 0.9 x V
and 0.1 x V
.
B
CC
CC
Note 17: Typical frequency shift due to aging is 0.5%. Aging stressing includes Level 1 moisture reflow preconditioning (24hr
+125°C bake, 168hr 85°C/85%RH moisture soak, and 3 solder reflow passes +240 +0/-5°C peak) followed by 1000hr
max V
biased 125°C HTOL, 1000 temperature cycles at -55°C to +125°C, 96hr 130°C/85%RH/5.5V HAST and 168hr
CC
121°C/2 ATM Steam/Unbiased Autoclave.
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5