5076 series
FUNCTIONAL DESCRIPTION
Oscillation Start-up Detector Function
The devices also feature an oscillation start-up detector circuit. This circuit functions to disable the outputs
until the oscillation starts. This prevents unstable oscillator output at oscillator start-up when power is applied.
TYPICAL PERFORMANCE (5076B1)
The following characteristics measured using the crystal below. Note that the characteristics will vary with the
crystal used.
I
Crystal used for measurement
Parameter
C0 [pF]
γ
(= C0/C1)
f
O
= 27MHz
1.5
300
I
Crystal parameters
L1
C1
R1
C0
Frequency Pulling Range
250
200
150
Pulling range [ppm]
100
50
0
−50
−100
−150
−200
−250
0.0
Pulling Sensitivity
250
200
Sensitivity [ppm/V]
150
100
50
0
0.3
0.6
0.9
V
C
[V]
1.2
1.5
1.8
0.0
0.3
0.6
0.9
V
C
[V]
1.2
1.5
1.8
V
DD
= 1.8V, f
OUT
= 27MHz, Ta = R.T.
V
DD
= 1.8V, f
OUT
= 27MHz, Ta = R.T.
Measurement circuit
VDD
Crystal
XT
XTN
VC
0.1µF
Q
VSS
C
LOUT
= 15pF
(Including probe
capacitance)
SEIKO NPC CORPORATION —9