Intersil EL6201CY-T13 Low power 430mhz hfm oscillator w/disable Datasheet

EL6201
®
Data Sheet
Low Power 430MHz HFM Oscillator
w/Disable
The EL6201 is a solid state high performance laser
modulation oscillator with external resistor adjustable
frequency and amplitude. The EL6201 is available in both
the 8-pin MSOP and the 5-pin SOT-23, to enable device
placement close to the laser for reduced EMI.
The oscillator frequency is set by connecting a single
external resistor from the RFREQ pin to ground. The
oscillator current output amplitude is set by connecting a
single external resistor from the RAMP pin to ground. The
oscillator in the MSOP package also contains a high speed
output disable function using the OE pin. The OE pin can be
driven by a high speed timing signal to control precise laser
modulation during read/write operations. The output current
is disabled when a logical zero ‘L’ is driven to the CE pin.
Supply current is reduced to microamps when CE = LOW.
The EL6201 has internal supply bypass capacitors to reduce
oscillation noise spread through supply connections.
October 25, 2004
FN7216.2
Features
• Small SOT-23 and MSOP8 packages
• Frequency to 430MHz min
• Amplitude to 25mAP-P min
• Output tristate function (MSOP8)
• Power-down function (MSOP8)
• Single +3.5V to +5.0V supply
• Simple to use - only two external resistors required
• Independent resistor setting for frequency and amplitude
• Pb-Free Available (RoHS Compliant)
Applications
• DVD players
• DVD-ROM drives
• DVD-RAM drives
• CD-RW drives
• MO drives
Ordering Information
PART NUMBER
PACKAGE
TAPE & REEL PKG. DWG. #
• Optical pickup head assembly
• Laser diode modulation
EL6201CY
8-Pin MSOP
-
MDP0043
EL6201CY-T7
8-Pin MSOP
7” (1.5K pcs)
MDP0043
EL6201CY-T13
8-Pin MSOP
13” (2.5K pcs)
MDP0043
• Communications lasers
EL6201CYZ
(See Note)
8-Pin MSOP
(Pb-free)
-
MDP0043
Pinouts
EL6201CYZ-T7
(See Note)
8-Pin MSOP
(Pb-free)
7” (1.5K pcs)
MDP0043
EL6201CYZ-T13
(See Note)
8-Pin MSOP
(Pb-free)
13” (2.5K pcs)
MDP0043
EL6201CW-T7
5-Pin SOT-23
7” (3K pcs)
MDP0038
EL6201CW-T7A
5-Pin SOT-23
7” (250 pcs)
MDP0038
EL6201CWZ-T7
(See Note)
5-Pin SOT-23
(Pb-free)
7” (3K pcs)
MDP0038
EL6201CWZ-T7A
(See Note)
5-Pin SOT-23
(Pb-free)
7” (250 pcs)
MDP0038
NOTE: Intersil Pb-free products employ special Pb-free material sets;
molding compounds/die attach materials and 100% matte tin plate
termination finish, which are RoHS compliant and compatible with
both SnPb and Pb-free soldering operations. Intersil Pb-free products
are MSL classified at Pb-free peak reflow temperatures that meet or
exceed the Pb-free requirements of IPC/JEDEC J STD-020C.
1
• Local oscillator
EL6201
(5-PIN SOT-23)
TOP VIEW
1
VS
2
GND
3
IOUT
RFREQ
5
RAMP
4
EL6201
(8-PIN MSOP)
TOP VIEW
1
CE
VS
8
2
GND
IOUT
7
3
RFREQ
GND
6
4
RAMP
OE
5
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
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Copyright © Intersil Americas Inc. 2003-2004. All Rights Reserved. Elantec is a registered trademark of Elantec Semiconductor, Inc.
All other trademarks mentioned are the property of their respective owners.
EL6201
Absolute Maximum Ratings (TA = 25°C)
Voltages applied to:
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to +6.0V
RFREQ, RAMP . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to +6.0V
CE, OE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 to VCC
Power Dissipation (maximum) . . . . . . . . . . . . . . . . . . . . See Curves
Operating Ambient Temperature Range . . . . . . . . . . . 0°C to +75°C
Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . 125°C
Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35mA
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests
are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA
DC Electrical Specifications
VS = +5V, TA = 25°C, CE = HI, unless otherwise specified. RAMP = 6.67kΩ (IOUT = ±8.5mA), RFREQ =
833Ω (FO = 330MHz)
PARAMETER
DESCRIPTION
CONDITIONS
MIN
TYP
MAX
UNIT
20
27
mA
30
µA
10.5
mA
3.5
V
IS
Supply Current (Enabled)
CE = HIGH, OE = LOW
ISD
Supply Current (Disabled)
CE = LOW
ISTRI
Supply Current (Tristated)
OE = HIGH
6.5
VLOAD
Output Voltage Range
Maximum IOUTP-P
1.5
IOUTP-P
Output Current Accuracy
RAMP = 6.67k, IOUT = 2.5V to 3.0V
11
15
19
mA
IOS
Output Current DC offset
-2.5
0
+2.5
mA
VINL
Logic Input Low
0.8
V
VINH
Logic Input High
IINL
Logic Low Input Current
CE or OE at 0V
100
µA
IINH
Logic High Input Current
CE or OE at +5V
100
µA
MAX
UNIT
AC Electrical Specifications
PARAMETER
8.5
2.4
V
VS = +5V, TA = 25°C, RAMP = 6.67kΩ, RFREQ = 833Ω
DESCRIPTION
CONDITIONS
MIN
TYP
TCOSC
Oscillator Temperature Coefficient
FOSC
Initial Oscillator Frequency
Accuracy
FRANGE
Oscillator Frequency Range
500Ω ≤ RFREQ ≤ 7kΩ
ARANGE
Oscillator Amplitude Range
30kΩ ≤ RAMP ≤ 3kΩ
TON, CE
EN Delay Time to 50% IOUT
CE = Low to High
300
ns
TOFF, CE
EN Delay Time to 50% IOUT
CE = High to Low
10
ns
TON, OE
OE Delay Time to 50% IOUT
OE = Low to High
10
ns
TOFF,OE
OE Delay Time to 50% IOUT
OE = High to Low
10
ns
Duty Cycle
Measured from 25°C to 125°C die
temperature
600
270
400
MHz
80
430
MHz
7.5
25
mAP-P
40
2
330
ppm/°C
52
60
%
EL6201
Typical Performance Curves
600
600
IOUTp-p = 15mA
TA = 25°C
IOUTp-p = 15mA
TA = 25°C
500
FREQUENCY (MHz)
FREQUENCY (MHz)
500
400
300
200
100
400
300
200
100
0
0
0
1
2
3
4
0
5
1
RFREQ (kΩ)
2
3
1000Ω/RFREQ
FIGURE 1. FREQUENCY vs RFREQ
FIGURE 2. FREQUENCY vs 1000Ω/RFREQ
40
35
35
30
IDEAL
FO = 330MHz
TA = 25°C
ACTUAL
25
25
IOUTp-p (mA)
IOUTp-p (mA)
30
20
15
20
15
FO = 330MHz
TA = 25°C
10
10
5
5
0
0
0
4
8
12
16
20
0
50
75
RAMP (kΩ)
100
125
150
175
200
427/RAMP (kΩ)
FIGURE 3. IOUTp-p vs RAMP
FIGURE 4. IOUTp-p vs 427/RAMP
180
35
160
30
140
25
PDISS (mW)
ISUPPLY (mA)
120
20
15
FO = 330MHz
IOUTp-p = 15mA
TA = 25°C
10
80
FO = 330MHz
IOUTp-p = 15mA
TA = 25°C
60
40
5
0
3.0
100
20
3.5
4.0
4.5
5.0
VSUPPLY (V)
FIGURE 5. ISUPPLY vs VSUPPLY
3
5.5
0
3.0
3.5
4.0
4.5
5.0
VSUPPLY (V)
FIGURE 6. DISSIPATION vs SUPPLY VOLTAGE
5.5
EL6201
Typical Performance Curves
(Continued)
18
320
17
310
16
FREQUENCY (MHz)
IOUTp-p (mA)
15
FO = 330MHz
RAMP = 6.5kΩ
TA = 25°C
14
13
12
11
300
290
280
RFREQ = 833Ω
IOUTp-p = 15mA
TA = 25°C
270
10
260
9
8
3.0
3.5
4.0
4.5
5.0
250
3.0
5.5
3.5
4.0
VSUPPLY (V)
FIGURE 7. IOUTP-P vs VSUPPLY
5.5
35
48.6
30
IOUTp-p = 15mA
TA = 25°C
48.4
ISUPPLY (mA)
DUTY CYCLE (%)
5.0
FIGURE 8. FREQUENCY vs VSUPPLY
48.8
48.2
RFREQ = 833Ω
RAMP = 6.5kΩ
TA = 25°C
48.0
25
20
15
47.8
47.6
3.0
10
3.5
4.0
4.5
5.0
5.5
100
0
200
VSUPPLY (V)
300
400
500
FREQUENCY (MHz)
FIGURE 9. DUTY CYCLE (%) vs VSUPPLY
FIGURE 10. ISUPPLY vs FREQUENCY
180
36
34
160
RFREQ = 833Ω
TA = 25°C
32
IOUTp-p = 15mA
VS = 5V
TA = 25°C
140
ISUPPLY (mA)
DISSIPATION (mW)
4.5
VSUPPLY (V)
120
100
30
28
26
24
80
22
60
20
0
100
200
300
400
FREQUENCY (MHz)
FIGURE 11. DISSIPATION vs FREQUENCY
4
500
0
5
10
15
20
25
30
IOUTp-p (mA)
FIGURE 12. ISUPPLY vs IOUTp-p
35
40
EL6201
Typical Performance Curves
58
0
56
-10
RELATIVE AMPLITUDE (dB)
IOUTp-p = 15mA
VS = 5V
TA = 25°C
54
DUTY CYCLE (%)
(Continued)
52
50
48
46
44
42
RFREQ = 833Ω
RAMP = 6.5k
TA = 25°C
-20
-30
-40
-50
-60
-70
-80
-90
40
0
100
300
200
400
-100
340
500
345
FREQUENCY (MHz)
350
355
360
365
FREQUENCY (MHz)
FIGURE 13. DUTY CYCLE vs FREQUENCY
FIGURE 14. OUTPUT SPECTRUM - WIDEBAND
28.0
20.5
27.5
26.5
IOUTp-p (mA)
ISUPPLY (mA)
RFREQ = 833Ω
RAMP = 6.5kΩ
20.0
FO = 330MHz
IOUTp-p = 15mA
27.0
26.0
25.5
19.5
19.0
25.0
18.5
24.5
24.0
18.0
0
25
50
75
100
125
0
25
DIE TEMPERATURE (°C)
FIGURE 15. ISUPPLY vs DIE TEMPERATURE
75
100
125
FIGURE 16. IOUTp-p vs DIE TEMPERATURE
48.5
380
RFREQ = 833Ω
RAMP = 6.5kΩ
375
RFREQ = 833Ω
RAMP = 6.5kΩ
370
FREQUENCY (MHz)
48.0
DUTY CYCLE (%)
50
DIE TEMPERATURE (°C)
47.5
47.0
46.5
365
360
355
350
345
46.0
340
45.5
335
0
25
50
75
100
125
DIE TEMPERATURE (°C)
FIGURE 17. DUTY CYCLE vs DIE TEMPERATURE
5
0
25
50
75
100
125
DIE TEMPERATURE (°C)
FIGURE 18. FREQUENCY vs DIE TEMPERATURE
EL6201
Typical Performance Curves
(Continued)
SEMI G42-88 SINGLE LAYER TEST BOARD
SEMI G42-88 SINGLE LAYER TEST BOARD
0.50
0.60
391mW
POWER DISSIPAION (W)
POWER DISSIPAION (W)
0.30
0.20
486 mW
0.50
θJA = 256°C/W
0.40
195mW
0.10
θJA = 206°C/W
0.40
0.30
243mW
0.20
0.10
0.00
0.00
0
25
50
75
100
125
0
25
AMBIENT TEMPERATURE (°C)
50
75
100
125
AMBIENT TEMPERATURE (°C)
FIGURE 19. SOT23-5 POWER DISSIPATION vs AMBIENT
TEMPERATURE
FIGURE 20. MSOP8 POWER DISSIPATION vs AMBIENT
TEMPERATURE
Typical Application Circuit
+5V
+5V
1
5
RFREQ
IDC
2
3
4
RAMP
C*
*Optional AC coupling
Applications Information
The EL6201 is designed to interface easily to laser diodes to
break up optical feedback resonant modes and thereby
reduce laser noise, but it is also generally useful as a 70MHz
- 430MHz oscillator. The first applications section will focus
on laser systems, and subsequent sections are of general
topics.
Laser Diode Applications
The output of the EL6201 is composed of a sourcing and a
sinking current source, switched alternately at the oscillator
frequency. The output voltage compliance is VS to ground,
with about 40Ω of series resistance. There is no severe
squarewave distortion when the output voltage approaches
the supply extremes, although the corners will be rounded.
Being a current-source output, the output bias voltage is set
by direct connection to the laser diode, which will appear as
a low AC impedance with a DC voltage from 1.6V to 2.5V.
Thus AC coupling from the EL6201 to the diode is
unnecessary. The duty cycle of the output is between 40%
6
and 60%, so the DC contribution from the EL6201 is only
±5% of the peak-to-peak output. This will cause little
perturbation of the diode’s DC bias current.
Although not necessary, capacitance coupling can be
employed. A series capacitive reactance of less than 30Ω is
recommended. A 20pF capacitor is thus appropriate at
330MHz. Benefits include no DC error current into the laser
diode, and an attenuation of low-frequency noise from the
EL6201. Disadvantages include perhaps 20% output AC
current loss.
While the diode AC impedance is generally in the low ohm
range, any interconnect will create around 8nH per cm. of
series inductance. Because the EL6201’s output is an AC
current source, higher load reactance due to series
inductance will cause the EL6201’s output voltage to swing
more than what a direct connection to the diode would
cause. At 400MHz and 15mAP-P output, just one cm. will
generate 0.3VP-P of extra driver signal at the fundamental,
and more at harmonic frequencies. The output current
EL6201
waveform is a squarewave, and inductive loads can cause as
much as 1V of overshoot. This does not mean that the
current delivered to the diode has overshoot - just the
voltage seen at the EL6201 output. Measurements show that
the EL6201 output edge rate is about 300psec - a speed
nearly impossible to deliver over practical interconnects to
the diode.
The L Series of Figure 22 must be carefully chosen. The
goal is to get a series reactance of around 70Ω at 300MHz,
so 40nH would suffice. The inductor should be shielded to
reduce EMI and have no saturation effects at the supply
currents drawn by the EL6201. Finally, there should be no
self-resonance at the operating frequency or its harmonics.
Also important is circuit-board layout. At the EL6201’s
operating frequencies, even the ground plane is not lowimpedance, and ground loops should be avoided. Figure 23
shows the output current loops:
RFREQ
SUPPLY
BYPASS
RAMP
SOURCING CURRENT LOOP
GND
(8-PIN
PACKAGE)
FIGURE 21. OUTPUT CURRENT WAVEFORM - 1GHz
BANDWIDTH
General Considerations
EMI and Grounding
From an EMI point of view, the edge rate of the output
current is much more important than that of the output
voltage. The components are generally small and will be
placed over a ground plane, so antenna effects that launch
voltage-mode EMI are small. Measurement shows that a
practical current edge rate is about 1nsec., so interconnect
should be over a ground plane and short to minimize
inductively launched EMI. Most EMI seems to come from the
supply wires connected to the diode/EL6201 board. The
internal resistance and inductance of capacitors prevents
perfect bypass action, and 150mVP-P noise on the lines is
common. There needs to be a lossy series inductance and
secondary bypass on the supply side to control signals from
propagating down the wires. Alternatively, a series supply
resistor can be used, which will also be useful in reducing
EL6201 power dissipation. Figure 22 shows the typical
connection.
L Series: 70Ω reactance at
300MHz (see text)
VS
EL6201
+5V
0.1µF
Chip
0.1µF
Chip
GND
FIGURE 22. RECOMMENDED SUPPLY BYPASSING
7
SINKING CURRENT LOOP
LOAD
FIGURE 23. OUTPUT CURRENT LOOPS
For the sourcing current loop, the current flows through the
supply bypass capacitor. The ground end of the bypass thus
should be connected directly to the EL6201 ground pin
(output ground pin of the 8-pin package). A long ground
return path will cause the bypass capacitor currents to
generate voltage drops in the ground plane of the circuit
board, and other components (such as RAMP and RFREQ)
will pick this up as an interfering signal. Similarly, the ground
return of the load should be considered as noisy and other
grounded components should not connect to this path.
Slotting the ground plane around the load’s return will
eliminate adjacent grounded components from seeing the
noise.
RFREQ and RAMP Interfaces
RAMP and RFREQ should be connected to the non-load side
of the power ground to avoid noise pick-up.
Figure 24 shows an equivalent circuit of these pins. VREF is
roughly 0.35V for RFREQ and more accurately 1.17V for
RAMP. The RAMP and RFREQ resistor should return to the
EL6201’s ground very directly lest they pick up highfrequency noise interference. They also should have minimal
capacitance to ground. Trimmer resistors can be used to
EL6201
adjust initial operating points, but they should be replaced
with fixed resistors for further testing.
+
VREF
-
Power-Down with the SOT-23 Package
The supply current of the EL6201 is low enough so that a
logic output can simply provide the supply current of the part
and effect power-down. This is most useful using the EL6201
in the SOT-23 package, which has no enable pin.
RF Applications
PIN
FIGURE 24. RFREQ AND RAMP PIN INTERFACE
External voltage sources can be coupled to the RAMP and
RFREQ pins to effect frequency or amplitude modulation or
adjustment. It is recommended that a coupling resistor be
installed in series with the control voltage and mounted
directly next to the EL6201 pin. This will keep the inevitable
high-frequency noise of the EL6201’s local environment from
propagating to the modulation source, and it will keep
parasitic capacitance at the EL6201 pin minimized.
Both inputs have several megahertz of bandwidth for analog
modulation. The output enable pin can be used to pass
digital modulation up to about 20Mbit/sec rates.
Power Dissipation Considerations
The EL6201 can easily interface to reactive loads, and is
adequate as a short-range modulated transmitter.
Remembering that the output circuitry looks like current
sources, impedance matching becomes a matter of
transforming the load impedance to an appropriate load line
for the EL6201. Also important is maintaining correct DC
bias voltage on the output. Since the output will have a net
DC current, capacitor coupling would allow the DC level to
drift toward a supply rail and increase output harmonic
products. In cases where such harmonics are important,
Figure 25 shows coupling the EL6201 output to a 50Ω load:
EL6201
L
0.001µF
IOUT
C1
50Ω
LOAD
C2
LCHOKE
VS
R2
R1
Supply current can be predicted by the equation:
12mA + I OUTp-p
I S = ------------------------------------------------------------------------------------------------12
4 + ( V S - 1.6V ) × FREQ × 8 × 10
The 12mA quantity represents the operating DC current of
the EL6201. This is also the current drawn from the supply
during output disable. The IOUT quantity is based on a
typical 50% duty cycle of output pull-up current, and the fact
that the peak-to-peak output current is about twice the pullup or pull-down currents. The VS quantity is due to CV2F
losses within the circuit, and the 8*10-12 quantity represents
internal capacitances that must be slewed at the operating
frequency. The 1.6V offset is a curve fit to measured data.
The internal die temperature operating range is -40°C to
+125°C. Internal temperature is equal to the ambient
temperature plus power dissipated times the thermal
resistance of the mounted package, θJA. For a mounted
MSOP-8 package, θJA is 206°C/W. The SOT-23 package
has a θJA of 256°C/W.
FIGURE 25. TUNED INTERFACE TO 50Ω LEAD
Digital Clock Applications
The EL6201 can be used as a digital clock source. If
unloaded, the output will simply traverse ground to VS. It is
recommended that the VS supply be isolated from the main
digital supply with an inductor or resistor, whose value is
chosen to drop about 250mV. In this way logic noise can be
isolated by the series component and the EL6201 local
bypass.
The rise- and fall-time of the output will be equal to
VS/(CLOAD*IOUTp-p/2). The output current should be the
smallest that can set an output rise-time, in the interest of
lowest dissipation.
The jitter is about 0.7% of period, RMS.
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Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
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