For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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8 - 1
HMC624LFLP4E
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
v00.0511
Functional Diagram
Electrical Specications,
TA = +25° C, 50 Ohm System, with Vdd = +5V & Vctl = 0/+5V (Unless Otherwise Noted)
The HMC624LFLP4E is a 6-bit GaAs IC Digital
Attenuator in a low cost leadless SMT package. This
versatile digital attenuator is suitable for a wide variety
of IF applications. The dual mode control interface
is CMOS/TTL compatible, and accepts either a
three wire serial input or a 6 bit parallel word. The
HMC624LFLP4E also features a user selectable
power up state and a serial output port for cascading
other Hittite serial controlled components. The
HMC624LFLP4E is housed in a RoHS compliant 4x4
mm QFN leadless package, and requires no external
matching components.
Parameter Frequency (MHz) Min. Typ. Max. Units
Insertion Loss 60 - 500 MHz 1.2 1.8 dB
Attenuation Range 60 - 500 MHz 31.5 dB
Return Loss (ATTIN, ATTOUT, All Atten. States) 60 - 500 MHz 20 dB
Attenuation Accuracy:
(Referenced to Insertion Loss) All Attenuation States
60 - 300 MHz
300 - 400 MHz
400 - 500 MHz
± (0.20 + 1% of Atten. Setting) Max
± (0.20 + 2% of Atten. Setting) Max
± (0.20 + 2.5% of Atten. Setting) Max
dB
dB
dB
Input Power for 0.1 dB Compression 60 - 100 MHz
100 - 500 MHz
30
32 dBm
Input Third Order Intercept Point
(Two-Tone Input Power = 10 dBm Each Tone)
60 - 100 MHz
100 - 500 MHz
50
55 dBm
Switching Speed tRise, tFall (10 / 90% RF)
rON, tOFF (50% LE to 10 / 90% RF) 60 - 500 MHz 30
60
ns
ns
Typical Applications Features
General Description
The HMC624LFLP4E is ideal for:
• Cellular/3G Infrastructure
• Repeaters & Access Points
• WiBro / WiMAX / 4G
• Microwave Radio & VSAT
• Test Equipment and Sensors
• IF Applications
0.5 dB LSB Steps to 31.5 dB
Power-Up State Selection
High Input IP3: +55 dBm
Low Insertion Loss: 1.2 dB
TTL/CMOS Compatible, Serial, Parallel
or Latched Parallel Control
<0.1 dB Typical Step Error @ 300 MHz
Single +3V or +5V Supply
24 Lead 4x4mm SMT Package: 16mm2
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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8 - 2
Output Return Loss
(Only Major States are Shown)
Input Return Loss
(Only Major States are Shown)
Normalized Attenuation
(Only Major States are Shown)
-35
-30
-25
-20
-15
-10
-5
0
50 150 250 350 450 550
NORMALIZED ATTENUATION (dB)
FREQUENCY (MHz)
Insertion Loss vs. Temperature
-2
-1.5
-1
-0.5
0
50 150 250 350 450 550
+25 C
+85 C
-40 C
INSERTION LOSS (dB)
FREQUENCY (MHz)
-50
-40
-30
-20
-10
0
50 150 250 350 450 550
RETURN LOSS (dB)
FREQUENCY (MHz)
-50
-40
-30
-20
-10
0
50 150 250 350 450 550
RETURN LOSS (dB)
FREQUENCY (MHz)
Bit Error vs. Frequency
(Only Major States are Shown)
Bit Error vs. Attenuation State
-1
-0.5
0
0.5
1
50 150 250 350 450 550
BIT ERROR (dB)
FREQUENCY (MHz)
31.5 dB
16 dB
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
0 4 8 12 16 20 24 28 32
60 MHz
100 MHz
200 MHz
300 MHz
400 MHz
500 MHz
BIT ERROR (dB)
ATTENUATION STATE (dB)
HMC624LFLP4E
v00.0511
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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8 - 3
Step Attn vs. Attn State, 60 - 300 MHz
IP3 @ Major Attenuation States
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 4 8 12 16 20 24 28 32
60 MHz
100 MHz
200 MHz
300 MHz
STEP ATTENUATION (dB)
ATTENUATION STATE (dB)
30
40
50
60
70
50 150 250 350 450 550
IP3 (dBm)
FREQUENCY (MHz)
Step Attn vs. Attn State, 400-500 MHz
P0.1dB vs. Temperature
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 4 8 12 16 20 24 28 32
400 MHz
500 MHz
STEP ATTENUATION (dB)
ATTENUATION STATE (dB)
20
25
30
35
40
50 150 250 350 450 550
+25 C
+85 C
-40 C
P0.1dB (dBm)
FREQUENCY (MHz)
HMC624LFLP4E
v00.0511
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
Serial Control Interface
The HMC624LFLP4E contains a 3-wire SPI compatible digital interface (SERIN, CLK, LE). The serial control interface
is activated when P/S is kept high. The 6-bit serial word must be loaded MSB rst. The positive-edge sensitive CLK
and LE requires clean transitions. If mechanical switches are used, sufficient debouncing should be provided. When
LE is high, 6-bit data in the serial input register is transferred to the attenuator. When LE is high CLK is masked to
prevent data transition during output loading.
When P/S is low, 3-wire SPI interface inputs (SERIN, CLK, LE) are disabled and the input register is loaded with
parallel digital inputs (D0-D5). When LE is high, 6-bit parallel data changes the state of the part per truth table.
For all modes of operations, the state will stay constant while LE is kept low.
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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HMC624LFLP4E
v00.0511
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
Bias Voltage Table
Vdd (V) Idd (Typ.) (mA)
30.12
50.15
PUP Truth TablePower-Up States
Control Voltage Input Reference
Insertion
Loss
D5 D4 D3 D2 D1 D0
High High High High High High 0 dB
High High High High High Low -0.5 dB
High High High High Low High -1 dB
High High High Low High High -2 dB
High High Low High High High -4 dB
High Low High High High High -8 dB
Low High High High High High -16 dB
Low Low Low Low Low Low -31.5 dB
Any combination of the above states will provide an attenuation
equal to the sum of the bits selected.
Truth Table
Timing Diagram (Latched Parallel Mode)
Parallel Mode
(Direct Parallel Mode & Latched Parallel Mode)
Note: The parallel mode is enabled when P/S is set to low.
Direct Parallel Mode - The attenuation state is changed by the control voltage inputs D0-D5 directly. The LE (Latch
Enable) must be at a logic high at all times to control the attenuator in this manner.
Latched Parallel Mode - The attenuation state is selected using the control voltage inputs D0-D5 and set while the
LE is in the Low state. The attenuator will not change state while LE is Low. Once all Control Voltage Inputs are at the
desired states the LE is pulsed. See timing diagram above for reference.
LE PUP1 PUP2 Relative Attenuation
000 -31.5
010 -24
001 -16
011 Insertion Loss
1X X 0 to -31.5 dB
Note: The logic state of D0 - D5 determines the power-
up state per truth table shown below when LE is high
at power-up.
If LE is set to logic LOW at power-up, the logic state of
PUP1 and PUP2 determines the power-up state of the
part per PUP truth table. If the LE is set to logic HIGH
at power-up, the logic state of D0-D5 determines the
power-up state of the part per truth table. The attenu-
ator latches in the desired power-up state approxi-
mately 200 ms after power-up.
Power-On Sequence
The ideal power-up sequence is: GND, Vdd, digital
inputs, RF inputs. The relative order of the digital
inputs are not important as long as they are powered
after Vdd / GND
Parameter Typ.
Min. serial period, tSCK 100 ns
Control set-up time, tCS 20 ns
Control hold-time, tCH 20 ns
LE setup-time, tLN 10 ns
Min. LE pulse width, tLEW 10 ns
Min LE pulse spacing, tLES 630 ns
Serial clock hold-time from LE, tCKN 10 ns
Hold Time, tPH. 0 ns
Latch Enable Minimum Width, tLEN 10 ns
Setup Time, tPS 2 ns
Control Voltage Table
State Vdd = +3V Vdd = +5V
Low 0 to 0.5V @ <1 µA 0 to 0.8V @ <1 µA
High 2 to 3V @ <1 µA 2 to 5V @ <1 µA
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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8 - 5
Absolute Maximum Ratings
RF Input Power (60-500 MHz) 28 dBm (T = +85 °C)
Digital Inputs (P/S, CLK, SERIN,
LE, PUP1, PUP2, D0-D5) -0.5 to Vdd +0.5V
Bias Voltage (Vdd) 5.6V
Channel Temperature 150 °C
Continuous Pdiss (T = 85 °C)
(derate 9.8 mW/°C above 85 °C) 0.635 W
Thermal Resistance 102 °C/W
Storage Temperature -65 to +150 °C
Operating Temperature -40 to +85 °C
ESD Sensitivity (HBM) Class 1B
ELECTROSTATIC SENSITIVE DEVICE
OBSERVE HANDLING PRECAUTIONS
Outline Drawing
NOTES:
1. LEADFRAME MATERIAL: COPPER ALLOY
2. DIMENSIONS ARE IN INCHES [MILLIMETERS]
3. LEAD SPACING TOLERANCE IS NON-CUMULATIVE.
4. PAD BURR LENGTH SHALL BE 0.15mm MAXIMUM.
PAD BURR HEIGHT SHALL BE 0.05mm MAXIMUM.
5. PACKAGE WARP SHALL NOT EXCEED 0.05mm.
6. ALL GROUND LEADS AND GROUND PADDLE MUST BE
SOLDERED TO PCB RF GROUND.
7. REFER TO HITTITE APPLICATION NOTE FOR SUGGESTED
LAND PATTERN.
Part Number Package Body Material Lead Finish MSL Rating Package Marking [1]
HMC624LFLP4E RoHS-compliant Low Stress Injection Molded Plastic 100% matte Sn MSL1 [2] H624LF
XXXX
[1] 4-Digit lot number XXXX
[2] Max peak reow temperature of 260 °C
Package Information
HMC624LFLP4E
v00.0511
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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8 - 6
HMC624LFLP4E
v00.0511
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
Pin Number Function Description Interface Schematic
1P/S
See truth table, control voltage
table and timing diagram.
2CLK
3SERIN
4LE
5, 14 GND These pins and package bottom
must be connected to RF/DC ground.
6, 13 ATTIN,
ATTOUT
These pins are DC coupled and matched to 50 Ohms.
Blocking capacitors are required. Select value based
on lowest frequency of operation.
7 - 12 ACG1 - ACG6
External capacitors to ground are required. Select values
for lowest frequency of operation. Place capacitors as
close to pins as possible.
15 SEROUT Serial input data delayed by 6 clock cycles.
16, 17
19 - 24
PUP2, PUP1
D5, D4, D3,
D2, D1, D0
See truth table, control voltage
table and timing diagram.
18 Vdd Supply voltage
Pin Descriptions
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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8 - 7
Application Circuit
HMC624LFLP4E
v00.0511
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
-35
-30
-25
-20
-15
-10
-5
0
0.1 1 10 100 1000
NORMALIZED ATTENUATION (dB)
FREQUENCY (MHz)
0
10
20
30
40
0.1 1 10 100 1000
+25 C
+85 C
-40 C
P0.1dB (dBm)
FREQUENCY (MHz)
Normalized Attenuation
Wideband Performance
P0.1dB vs. Temperature
Wideband Performance
Note: The capacitor value for C1-C6 shown in the stan-
dard Application Circuit as 0.1 uF will result in excellent
wideband small signal performance from 200 kHz to
500 MHz. Small signal operation to frequencies lower
than 200 kHz is possible through the proper selection of
capacitors C1-C6. Contact Hittite Applications Group for
proper selection of C1-C6 values for frequencies lower
than 200 kHz.
Note: The 0.1 dB Input Compression Point degrades for
low frequency operation. Typical 0.1 dB Input Compres-
sion Point at 60 MHz is +27 dBm tapering to +5 dBm at
250 kHz. The typical 0.1 dB Compression Point holds
constant at +5 dBm for frequencies lower than 250 kHz.
Hittite recommends that Absolute Maximum Input Power
Levels be maintained to less than the 0.1 dB Compression
point for reliable operation of the HMC624LFLP4E.
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
AttenuAtors - DIGItAL - sMt
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8 - 8
HMC624LFLP4E
v00.0511
0.5 dB LSB GaAs MMIC 6-BIT
DIGITAL ATTENUATOR, 60 - 500 MHz
Evaluation PCB
The circuit board used in the application should
use RF circuit design techniques. Signal lines
should have 50 Ohm impedance while the package
ground leads and exposed paddle should be con-
nected directly to the ground plane similar to that
shown. A sufficient number of via holes should be
used to connect the top and bottom ground planes.
The evaluation circuit board shown is available from
Hittite upon request.
List of Materials for Evaluation PCB EVAL01-HMC624LFLP4E [1]
Item Description
J1, J2 PCB Mount SMA Connector
J3 18 Pin DC Connector
J8, J11 DC Pin
C1 - C6 0.1 uF Capacitor, 0402 Pkg.
C7 - C8 1000 pF Capacitor, 0402 Pkg.
R1 - R14 100 kOhm Resistor, 0402 Pkg.
SW1, SW2 SPDT 4 Position DIP Switch
U1 HMC624LFLP4E Digital Attenuator
PCB [2] 117210 Evaluation PCB
[1] Reference this number when ordering complete evaluation PCB
[2] Circuit Board Material: Arlon 25FR