MAXIM DS1091LUA+027

Rev 0; 9/06
Automotive Temperature Range
Spread-Spectrum Econoscillator
The DS1091L is a low-cost clock generator that is factorytrimmed to output frequencies from 130kHz to 66.6MHz
with a nominal accuracy of ±0.25%. The device can also
produce a center- or down-dithered spread-spectrum
output with pin-selectable dither magnitude and rate.
Assembled in an 8-pin µMAX package, the DS1091L is
designed to operate with a 3.0V to 3.6V power supply
over the automotive temperature range (-40°C to
+125°C).
Applications
Automotive Infotainment
Features
♦ Spread-Spectrum Clock Output from 130kHz to
66.6MHz
♦ Operating Temperature Range of -40°C to +125°C
♦ Accuracy of ±1.75% Across Temperature and
Voltage
♦ Factory Trimmed
♦ Center-Dithered (DS1091LA) or Down-Dithered
(DS1091LB) Spread-Spectrum Output
♦ Pin-Selectable Center-Dither Magnitude of 0%,
±1%, ±2%, or ±4%
♦ Pin-Selectable Down-Dither Magnitude of 0%, -2%,
-4%, or -8%
POS Terminals
LCD Displays
♦ Pin-Selectable Dither Rate
Printers
♦ 3.0V to 3.6V Supply Operation
Industrial Control
♦ Lead-Free 8-Pin µMAX Package
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
SPREAD SPECTRUM
OUTPUT FREQUENCY (MHz)
DS1091LUA+027
-40°C to +125°C
8 µMAX
Center
27.0
DS1091LUA+033
-40°C to +125°C
8 µMAX
Center
33.3
DS1091LUA+066
-40°C to +125°C
8 µMAX
Center
66.6
DS1091LUA+xxx
-40°C to +125°C
8 µMAX
Center
Custom (Contact Factory)
DS1091LUB+027
-40°C to +125°C
8 µMAX
Down
27.0
DS1091LUB+033
-40°C to +125°C
8 µMAX
Down
33.3
DS1091LUB+066
-40°C to +125°C
8 µMAX
Down
66.6
DS1091LUB+xxx
-40°C to +125°C
8 µMAX
Down
Custom (Contact Factory)
+Denotes lead-free package.
xxx Denotes factory-programmed custom frequencies.
Email [email protected] for information/questions concerning custom frequencies.
Typical Operating Circuit
Pin Configuration
VCC
fOUT
OUT
VCC
VCC
DECOUPLING
CAPACITORS
GND
SEL1
1
8
2
7
3
DS1091L
6
5
4
TOP VIEW
DR
N.C.
N.C.
SEL0
VCC
OUT
1
8
VCC
2
7
N.C.
GND
3
6
N.C.
SEL1
4
5
SEL0
DS1091L
DR
µMAX
μMAX
μMAX
88 µMAX
______________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
DS1091L
General Description
DS1091L
Automotive Temperature Range
Spread-Spectrum Econoscillator
ABSOLUTE MAXIMUM RATINGS
Voltage on VCC Relative to Ground.......................-0.5V to +6.0V
Voltage on DR, SEL0, SEL1 Relative
to Ground* ..............................................-0.5V to (VCC + 0.5V)
Operating Temperature Range .........................-40°C to +125°C
Storage Temperature Range .............................-55°C to +125°C
Soldering Temperature...................See J-STD-020 Specification
*This voltage must not exceed 6.0V.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
(TA = -40°C to +125°C.)
PARAMETER
SYMBOL
Supply Voltage
VCC
High-Level Input Voltage
(SEL0, SEL1, DR)
VIH
Low-Level Input Voltage
(SEL0, SEL1, DR)
VIL
CONDITIONS
(Note 1)
MIN
TYP
MAX
UNITS
3.0
3.3
3.6
V
0.7 x
VCC
VCC +
0.3
V
-0.3
0.3 x
VCC
V
MAX
UNITS
DC ELECTRICAL CHARACTERISTICS
(TA = -40°C to +125°C; VCC = +3.0V to +3.6V, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
High-Level Output Voltage (OUT)
VOH
IOH = -4mA, VCC = 3.0V
Low-Level Output Voltage (OUT)
VOL
IOL = 4mA
2.4
0.4
V
V
High-Level Input Current
(SEL0, SEL1, DR)
IIH
VCC = 3.6V
1
µA
Low-Level Input Current
(SEL0, SEL1, DR)
IIL
VIL = 0
Supply Current (Active)
ICC
(Note 2)
-1
µA
16
mA
MAX
UNITS
66.6
MHz
AC ELECTRICAL CHARACTERISTICS
(TA = -40°C to +125°C; VCC = +3.0V to +3.6V, unless otherwise noted.)
PARAMETER
Output Frequency Range
Output Center Frequency Tolerance
SYMBOL
fOUT
ΔfOUT
Power-Up Time
tPU
Load Capacitance
CL
2
CONDITIONS
MIN
TYP
(Note 3)
0.130
VCC = 3.3V, TA = +25°C
-0.25
Across TA and VCC
-1.75
+1.75
0°C to +70°C, across VCC
-1.2
+1.2
0
(Note 4)
_____________________________________________________________________
15
+0.25
%
0.1
ms
50
pF
Automotive Temperature Range
Spread-Spectrum Econoscillator
(TA = -40°C to +125°C; VCC = +3.0V to +3.6V.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
< 33.3MHz (Note 3)
Duty Cycle
UNITS
50
≥ 33.3MHz (Note 3)
40
%
60
Jitter (RMS), 50MHz
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
MAX
0.3
%
All voltages are referenced to ground. Currents entering the IC are specified positive and currents exiting the IC are negative.
Supply current measured with CL = 15pF, VCC = 3.6V, TA = 25°C, fOUT = 66.6MHz, no dither.
No dither.
Guaranteed by design.
For aging characteristics, contact factory.
Typical Operating Characteristics
(TA = +25°C, VCC = 3.3V, unless otherwise noted.)
FREQUENCY VARIATION (%)
VCC = 3.3V
8.2
8.0
VCC = 3.0V
7.8
0.75
0.25
fOUT = 130kHz
-0.25
fOUT = 66MHz
-0.75
7.4
-10
20
0.15
0.10
0.05
fOUT = 66MHz
0.00
-0.05
fOUT = 130kHz
-0.10
50
80
110
NO DITHER
-0.20
-1.75
-0.25
-40
-10
TEMPERATURE (°C)
20
50
80
110
3.0
3.1
3.2
TEMPERATURE (°C)
3.4
3.5
3.6
DUTY CYCLE vs. TEMPERATURE
DUTY CYCLE vs. VCC
60
51.5
58
56
DUTY CYCLE (%)
fOUT = 66MHz
50.5
fOUT = 130kHz
50.0
49.5
DS1091L toc05
52.0
51.0
3.3
VCC (V)
DS1091L toc04
-40
0.20
-0.15
-1.25
7.6
DUTY CYCLE (%)
ICC (mA)
8.6
0.25
DS1091L toc03
1.25
8.8
8.4
VCC = 3.3V
NO DITHER
FREQUENCY VARIATION (%)
VCC = 3.6V
DS1091L toc02
1.75
DS1091L toc01
9.2
9.0
FREQUENCY VARIATION (%)
vs. VOLTAGE
FREQUENCY VARIATION (%)
vs. TEMPERATURE
ICC vs. TEMPERATURE
54
fOUT = 66MHz
52
50
fOUT = 130kHz
48
46
49.0
44
NO DITHER
48.5
42
48.0
40
3.0
3.1
3.2
3.3
VCC (V)
3.4
3.5
3.6
NO DITHER
-40
-15
10
35
60
85
110
TEMPERATURE (°C)
_____________________________________________________________________
3
DS1091L
AC ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics (continued)
(TA = +25°C, VCC = 3.3V, unless otherwise noted.)
2.5
2.0
1.5
3.0
FALL TIME
= 1.13ns
TYPICAL
AT 12pF LOAD
2.5
2.0
1.5
0
RBW = 120kHz
0%
CENTER DITHER
-10
8dB
±2%
11dB
14dB
±4%
-15
-20
1.0
1.0
0.5
0.5
-30
0.0
0.0
-35
-25
31.9
TIME (ns)
fOUT = 33.3MHz
±1%
-5
ATTENUATION (dB)
RISE TIME
= 1.02ns
TYPICAL
AT 12pF LOAD
3.5
OUTPUT (V)
3.0
5
DS1091L toc07
DS1091L toc06
3.5
SPECTRUM ATTENUATION vs. FREQUENCY
AT DIFFERENT DITHER AMPLITUDES
OUTPUT FALL TIME
DS1091L toc08
OUTPUT RISE TIME
OUTPUT (V)
DS1091L
Automotive Temperature Range
Spread-Spectrum Econoscillator
32.4
TIME (ns)
32.9
33.4
33.9
34.4
34.9
FREQUENCY (MHz)
Pin Description
PIN
µMAX8
4
NAME
FUNCTION
1
OUT
Spread-Spectrum Clock Output
2
VCC
Supply Voltage
3
GND
Ground
4
SEL1
5
SEL0
6, 7
N.C.
8
DR
Spread Spectrum Dither Magnitude Select Inputs. Selects dither magnitude (see Table 1).
No Connection
Spread-Spectrum Dither Rate Selector. Selects dither rate (see Table 2).
_____________________________________________________________________
Automotive Temperature Range
Spread-Spectrum Econoscillator
DS1091L
VCC
fMOSC
GND
fMOSC
FACTORY-PROGRAMMED
MASTER OSCILLATOR
DITHER RATE DIVIDER
DR
fDITHER
TRIANGLE WAVE GENERATOR
(DITHER %)
SEL1
FACTORY-PROGRAMMED
PRESCALER
VCC
fOUT
OUT
SEL0
WHERE fMOSC IS THE MASTER OSCILLATOR FREQUENCY.
Detailed Description
The DS1091L is a clock generator that is capable of
output frequencies from 130kHz to 66.6MHz over the
full automotive temperature range (-40°C to +125°C).
The device also is capable of producing a spreadspectrum (dithered) square-wave output using four pinselectable dither percentages. Both center (DS1091LA)
and down (DS1091LB) dithering options are available.
The device also features two selectable dither rates.
The DS1091L is shipped from the factory programmed
to a customer-specified frequency.
Spread Spectrum
The DS1091L has the ability to reduce radiated emission peaks. The dither percentage is controlled by the
state of the SEL0 and SEL1 pins. The output frequency
can be dithered at 0%, ±1%, ±2%, and ±4%, centered
around the programmed frequency (for the DS1091LB
this can be down dithered by 0%, -2%, -4%, and -8%).
The two select pins SEL0 and SEL1 provide a means of
selecting the dither magnitudes as follows:
A triangle wave generator injects a control signal into
the master oscillator to dither its output. The dither rate
is a function of the output frequency, fOUT as well as the
setting of the DR pin (see the equation below). Figure 1
shows a plot of the output frequency versus time.
DITHER RATE =
fOUT
2n
where n is defined in Table 2 as a function of output frequency. For example, for an output frequency of
27.0MHz, the dither rate would be 13.2kHz for DR = 0
and 6.6kHz for DR = 1.
Table 1.
SEL1
SEL0
LOGIC LEVEL LOGIC LEVEL
DITHER MAGNITUDE
DS1091LA
DS1091LB
0
0
No Dither
No Dither
0
1
±1%
-2%
1
0
±2%
-4%
1
1
±4%
-8%
Table 2.
OUTPUT FREQUENCY fOUT
(MHz)
n
fOUT (min)
fOUT (max)
DR = LOGIC
LEVEL 1
DR = LOGIC
LEVEL 0
0.130
0.260
4
5
0.261
0.521
5
6
0.522
1.042
6
7
1.043
2.083
7
8
2.084
4.167
8
9
4.168
8.333
9
10
8.334
16.667
10
11
16.668
33.333
11
12
33.334
66.667
12
13
_____________________________________________________________________
5
DS1091L
Block Diagram
Application Information
IF DITHER AMOUNT = 0%
fOUT
PROGRAMMED fOUT+
(1%, 2%, OR 4% OF fOUT)
PROGRAMMED fOUT
PROGRAMMED fOUT(1%, 2%, OR 4% OF fOUT)
DITHER
AMOUNT
(±1%, ±2%,
OR ±4%)
1
DITHER FREQ
Power-Supply Decoupling
To achieve best results, it is highly recommended that
decoupling capacitors are used on the IC power-supply
pins. Typical values of decoupling capacitors are 0.01µF
and 0.1µF. Use a high-quality, ceramic, surface-mount
capacitor, and mount it as close as possible to the VCC
and GND pins of the IC to minimize lead inductance.
Requesting Custom Frequencies
TIME
Email [email protected] for
information/questions concerning custom frequencies.
Figure 1A. Center Dithered
Power-Up
Upon the application of power, the DS1091L output is
held in the low state until t PU has elapsed. This
removes any possibility of erroneous output transitions
during initial power-up.
DS1091L Frequency Spreading Profile as a
Function of Dither %
Chip Topology
TRANSISTOR COUNT: 4887
SUBSTRATE CONNECTED TO GROUND
Package Information
For the latest package outline information, go to
www.maxim-ic.com/DallasPackInfo.
IF DITHER AMOUNT = 0%
PROGRAMMED fOUT
DITHER
AMOUNT
(-2%, -4%,
OR -8%)
PROGRAMMED fOUT(2%, 4%, OR 8% OF fOUT)
fOUT
DS1091L
Automotive Temperature Range
Spread-Spectrum Econoscillator
1
DITHER FREQ
TIME
Figure 1B. Down Dithered
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
6 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2006 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
is a registered trademark of Dallas Semiconductor Corporation.
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