5075 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 (5075B1)
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
0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50
V
C
[V]
Pulling range [ppm]
250
200
150
100
50
0
−50
−100
−150
−200
−250
0.00 0.30 0.60 0.90 1.20 1.50 1.65 1.80 2.10 2.40 2.70 3.00 3.30
V
C
[V]
V
DD
= 2.5V, f
OUT
= 27MHz, Ta = R.T.
V
DD
= 3.3V, f
OUT
= 27MHz, Ta = R.T.
Pulling Sensitivity
250
200
Sensitivity [ppm/V]
V
DD
= 2.5V
150
100
V
DD
= 3.3V
50
0
0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0 3.3
V
C
[V]
Measurement circuit
VDD
Crystal
XT
XTN
VC
0.1µF
Q
VSS
C
LOUT
= 15pF
(Including probe
capacitance)
V
DD
= 2.5V, 3.3V, f
OUT
= 27MHz, Ta = R.T.
SEIKO NPC CORPORATION —9
NPC [ NIPPON PRECISION CIRCUITS INC ]
