Datasheet

LTC6990
3
6990fc
For more information www.linear.com/LTC6990
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
f
OUT
Output Frequency Recommended Range: R
SET
= 50k to 800k
Extended Range: R
SET
= 25k to 800k
0.488
0.488
1000
2000
kHz
kHz
∆f
OUT
Frequency Accuracy (Note 4) Recommended Range
R
SET
= 50k to 800k
l
±0.8 ±1.5
±2.2
%
%
Extended Range
R
SET
= 25k to 800k
l
±2.4
±3.2
%
%
∆f
OUT
/∆T
Frequency Drift Over Temperature
l
±0.005 %/°C
∆f
OUT
/∆V
+
Frequency Drift Over Supply V
+
= 4.5V to 5.5V
V
+
= 2.25V to 4.5V
l
l
0.23
0.06
0.55
0.16
%/V
%/V
Long-T
erm Frequency Stability (Note 11) 90 ppm/√kHr
Period Jitter (Note 10) N
DIV
= 1 0.38 %
P-P
N
DIV
= 2 0.22
0.027
%
P-P
%
RMS
N
DIV
= 128 0.022
0.004
%
P-P
%
RMS
Duty Cycle N
DIV
= 1, R
SET
= 25k to 800k
N
DIV
> 1, R
SET
= 25k to 800k
l
l
47
48
50
50
53
52
%
%
BW Frequency Modulation Bandwidth 0.
4•f
OUT
kHz
t
S
Frequency Change Settling Time
(Note 9)
t
MASTER
= t
OUT
/N
DIV
6•t
MASTER
µs
Analog Inputs
V
SET
Voltage at SET Pin
l
0.97 1.00 1.03 V
∆V
SET
/∆T
V
SET
Drift Over Temperature
l
±75 µV/°C
∆V
SET
/∆V
+
V
SET
Drift Over Supply –150 µV/V
∆V
SET
/∆I
SET
V
SET
Droop with I
SET
–7 Ω
R
SET
Frequency-Setting Resistor Recommended Range
Extended Range
l
l
50
25
800
800
kΩ
kΩ
V
DIV
DIV Pin Voltage
l
0 V
+
V
∆V
DIV
/V
+
DIV Pin Valid Code Range (Note 5) Deviation from Ideal V
DIV
/V
+
= (DIVCODE + 0.5)/16
l
±1.5 %
DIV Pin Input Current
l
±10 nA
Power Supply
V
+
Operating Supply Voltage Range
l
2.25 5.5 V
Power-On Reset Voltage R
SET
= 25k to 800k
l
1.95 V
I
S
Supply Current R
L
= ∞, N
DIV
= 1, R
SET
= 50k V
+
= 5.5V
V
+
= 2.25V
l
l
235
145
283
183
µA
µA
R
L
= ∞, N
DIV
= 1 R
SET
= 800k V
+
= 5.5V
V
+
= 2.25V
l
l
71
59
105
92
µA
µA
R
L
= ∞, N
DIV
= 128, R
SET
= 50k V
+
= 5.5V
V
+
= 2.25V
l
l
137
106
180
145
µA
µA
R
L
= ∞, N
DIV
= 128, R
SET
= 800k V
+
= 5.5V
V
+
= 2.25V
l
l
66
56
100
90
µA
µA
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. Test conditions are V
+
= 2.25V to 5.5V, OE = V
+
, DIVCODE = 0 to 15
(N
DIV
= 1 to 128), R
SET
= 50k to 800k, R
LOAD
= 5k, C
LOAD
= 5pF unless otherwise noted.