MICROTUNE MT1550

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MT1550 UPSTREAM
AMPLIFIER
PRODUCT BRIEF
RF SILICON AND SYSTEMS SOLUTIONS
FOR BROADBAND COMMUNICATIONS, AUTOMOTIVE ELECTRONICS AND WIRELESS CONNECTIVITY
The MT1550 is a low-cost
programmable-gain power amplifier
IC for use in CATV upstream
applications. The Microtune®
MT1550 is a 3.3 volt part optimized
®
for the DOCSIS 1.0, 1.1, 2.0 and
programmable gain upstream
Euro-DOCSIS™ upstream standard.
An on-chip input anti-aliasing filter is
included to reduce external system
costs.
The device’s specified frequency
range is from 5 MHz to 65 MHz, with
an output P1dB > 67 dBmV through
a 1:1 impedance-ratio transformer.
A 3-wire digital serial bus controls
the variable gain, with gain control
available in 1 dB steps and a
nominal 59 dB gain range.
The MT1550 may be disabled via
an external control pin. The transmitdisable mode not only minimizes
output noise by shutting off the
output stage, but also maintains its
output impedance at nominal levels.
Output transients are nominally less
than 16 mVp-p at 61 dBmV output
level during transmit enable/disable
switching.
Operating from a single 3.3 V
supply, the amplifier typically draws
247 mA at maximum gain or
minimum attenuation. Additional
internal circuitry reduces the
amplifier’s power consumption
depending on gain setting.
Transmit-disable mode reduces the
typical current draw to 60 mA, while
shutdown mode further reduces it to
85 µA.
The MT1550 is available in a 20pin Quad Flat No-Lead (QFN)
package with an exposed pad for
the extended industrial temperature
range of -40°C to +85°C.
amplifier with integrated antialiasing filter.
MT1550 Upstream Amplifier
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Cable modems
Telephony over cable
Set-top box CATV
FEATURES
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Integrated on-chip antialiasing filter
P1dB of 67 dBmV
Low power-up/down
transients of 16 mVp-p typical
at 61 dBmV output
Ultra low third harmonic
distortion
Single 3.3 V supply
59 dB gain range
Gain programmable in 1 dB
steps
Low transmit output noise
floor: -50 dBmV in 160 kHz
Low transmit-disable output
noise: -68 dBmV
Two power-down modes
DOCSIS 1.0, 1.1, 2.0 and
Euro-DOCSIS compatible
M I C R O T U N E
The MT1550 is a 3.3V
MT1550 APPLICATIONS
M T15 50 UPSTR EAM AMPLI FIER
GND2
16
V
µA
Vcc2
85
17
UNIT
Vcsns
MAX
3.45
125
18
TYP
Vcc1
MIN
3.15
19
PARAMETER
Supply voltage
Supply current, shutdown mode
Vrsns
DC ELECTRICAL CHARACTERISTICS
20
PRODUCT BRIEF
SUPPLY CURRENT, TRANSMIT MODE, FILTER ENABLED
Gain code = 52 to 63
247
mA
0
V
V
µA
DIGITAL INPUT
High voltage
Low voltage
Current
2.0
0.7
AC ELECTRICAL CHARACTERISTICS
PARAMETER
MIN
TYP
Output 1dB compression point
Output step size
MAX
UNIT
70
1
dBmV
dB
-30
29
dB
dB
1.1
1.5
dB
dB
GND1
1
15
NC
Vin+
2
14
Vout+
Vin-
3
13
Vout-
DGND
4
12
NC
CS
5
11
Vcm
9
10
GND2
8
TXEN
SHDN
7
Fin = 42MHz
Fin = 65MHz
SCLK
GAIN RESPONSE
6
Gain code = 4
Gain code = 63
SDA
VOLTAGE GAIN
MT1550 Pin Diagram
TXEN
1.5
16
µs
µs
64
mVp-p
7
mVp-p
INPUT/OUTPUT
Input impedance
Output return loss, Z0 = 75Ω
1.55
kΩ
dB
16
VCC2
5
VCC1
TXEN enable/disable time
TXEN transient duration
TXEN transient step size, VOUT =
61dBmV
TXEN transient step size, min gain
Anti-Alias
Filter
Variable
Attenuator
Power
Amp
Vcc
VOUT+
1:1
Ohms
VIN+
VCM
0.1 µF
CEXT
STRESS RATINGS
UNIT
5.5
V
−0.7
VCC + 0.7
V
+125
°C
Junction temperature
Storage temperature range
Lead temperature (soldering, 4 seconds)
-40
+150
°C
+245
°C
Serial
Interface
CSNS
PA
Control
VRSNS
0.1 µF
RSNS
4.70 kΩ
1%
TXEN
-0.7
Input voltage levels (all inputs), VCM
Filter
Tuning
SCLK
VOUT+, VOUT-
VOUT-
CS
V
SDA
5
SHDN
MAX
-0.7
DGND
MIN
VCSNS
PARAMETER
VCC (VCC1, VCC2)
VIN-
59 pF
5%
MT1550 Block Diagram
Microtune, Inc., 2201 Tenth Street, Plano, TX 75074, USA
Tel: +1-972-673-1600, Fax: +1-972-673-1602, E-mail: [email protected], Web site: www.microtune.com
For a detailed list of design centers, sales offices, and sales representatives, visit our Web site at www.microtune.com.
The information in this document is believed to be accurate and reliable. Microtune assumes no responsibility for any consequences arising from the use of this information, nor from any infringement of patents or
the rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or other rights of Microtune. The information in this publication replaces and supersedes all
information previously supplied, and is subject to change without notice. The customer is responsible for assuring that proper design and operating safeguards are observed to minimize inherent and procedural
hazards. Microtune assumes no responsibility for applications assistance or customer product design.
The devices described in this document are not authorized for use in medical, life-support equipment, or any other application involving a potential risk of severe property or environmental damage, personal injury,
or death without prior express written approval of Microtune. Any such use is understood to be entirely at the user’s risk.
Microtune is a registered trademark of Microtune, Inc. MicroTuner, MicroStreamer, VideoCaster, DataCaster, and the Microtune logo are trademarks of Microtune, Inc. All other trademarks belong to their respective
companies.
Microtune’s products are protected by one or more of the following U.S. patents: DE10011662; GB1026825; ES1026825; DE19628727; DE19904588.7-09; DE348698; FR348698; GB348698; IT348698; DE3821716;
US5,933,946; DE50000802.7-08; DE552624 and additional patents pending or filed.
Entire contents Copyright © 1996 - 2005 Microtune, Inc.
PB-00058 — Rev 1.2
072105
October 2005
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