LMH6505MA/NOPB [TI]

宽带、低功耗、dB 线性可变增益放大器 | D | 8 | -40 to 85;
LMH6505MA/NOPB
型号: LMH6505MA/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

宽带、低功耗、dB 线性可变增益放大器 | D | 8 | -40 to 85

放大器 PC 光电二极管
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LMH6505  
www.ti.com  
SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
LMH6505 Wideband, Low Power, Linear-in-dB, Variable Gain Amplifier  
Check for Samples: LMH6505  
Near ideal input characteristics (i.e. low input bias  
1
FEATURES  
current, low offset, low pin 3 resistance) enable the  
device to be easily configured as an inverting  
amplifier as well.  
2
VS = ±5V, TA = 25°C, RF = 1 k, RG = 100, RL =  
100, AV = AVMAX = 9.4 V/V, Typical Values  
Unless Specified.  
To provide ease of use when working with a single  
supply, the VG range is set to be from 0V to +2V  
relative to the ground pin potential (pin 4). VG input  
impedance is high in order to ease drive requirement.  
In single supply operation, the ground pin is tied to a  
"virtual" half supply.  
3 dB BW 150 MHz  
Gain Control BW 100 MHz  
Adjustment Range (<10 MHz) 80 dB  
Gain Matching (Limit) ±0.50 dB  
Supply Voltage Range 7V to 12V  
Slew Rate (Inverting) 1500 V/μs  
Supply Current (No Load) 11 mA  
Linear Output Current ±60 mA  
Output Voltage Swing ±2.4V  
The LMH6505’s gain control is linear in dB for a large  
portion of the total gain control range from 0 dB down  
to 85 dB at 25°C, as shown below. This makes the  
device suitable for AGC applications. For linear gain  
control applications, see the LMH6503 datasheet.  
The LMH6505 is available in either the 8-Pin SOIC or  
the 8-Pin VSSOP package. The combination of  
minimal external components and small outline  
packages allows the LMH6505 to be used in space-  
constrained applications.  
Input Noise Voltage 4.4 nV/Hz  
Input Noise Current 2.6 pA/Hz  
THD (20 MHz, RL = 100, VO = 2 VPP) 45 dBc  
APPLICATIONS  
30  
12  
11  
Variable Attenuator  
AGC  
10  
10  
9
125°C  
25°C  
-55°C  
-10  
-30  
-50  
-70  
-90  
Voltage Controlled Filter  
Video Imaging Processing  
8
7
dB  
6
5
125°C  
25°C  
V/V  
DESCRIPTION  
4
3
2
1
The LMH6505 is a wideband DC coupled voltage  
controlled gain stage followed by a high speed  
current feedback operational amplifier which can  
directly drive a low impedance load. The gain  
adjustment range is 80 dB for up to 10 MHz which is  
accomplished by varying the gain control input  
voltage, VG.  
-55°C  
0
-0.5  
0
0.5  
1
1.5  
2
V
(V)  
G
Figure 1. Gain vs. VG  
Maximum gain is set by external components, and  
the gain can be reduced all the way to cutoff. Power  
consumption is 110 mW with a speed of 150 MHz  
and a gain control bandwidth (BW) of 100 MHz.  
Output referred DC offset voltage is less than 55 mV  
over the entire gain control voltage range. Device-to-  
device gain matching is within ±0.5 dB at maximum  
gain. Furthermore, gain is tested and ensured over a  
wide range. The output current feedback op amp  
allows high frequency large signals (Slew Rate =  
1500 V/μs) and can also drive a heavy load current  
(60 mA) ensured.  
Typical Application  
V
G
+
V
1
8
2
3
V
IN  
6
R
1 kW  
7
F
R
100W  
L
R
100W  
5
G
4
-
V
Figure 2. AVMAX = 9.4 V/V  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
All trademarks are the property of their respective owners.  
2
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2005–2013, Texas Instruments Incorporated  
LMH6505  
SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
www.ti.com  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
Absolute Maximum Ratings(1)(2)  
(3)  
ESD Tolerance  
Human Body Model  
Machine Model  
2000V  
200V  
Input Current  
±10 mA  
(4)  
Output Current  
120 mA  
Supply Voltages (V+ - V)  
Voltage at Input/ Output pins  
Storage Temperature Range  
Junction Temperature  
12.6V  
V+ +0.8V, V0.8V  
65°C to 150°C  
150°C  
Soldering Information:  
Infrared or Convection (20 sec)  
Wave Soldering (10 sec)  
235°C  
260°C  
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for  
which the device is intended to be functional, but specific performance is not ensured. For ensured specifications, see the Electrical  
Characteristics.  
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and  
specifications.  
(3) Human Body Model, applicable std. MIL-STD-883, Method 3015.7. Machine Model, applicable std. JESD22-A115-A (ESD MM std. of  
JEDEC). Field-Induced Charge-Device Model, applicable std. JESD22-C101-C (ESD FICDM std. of JEDEC).  
(4) The maximum output current (IOUT) is determined by device power dissipation limitations or value specified, whichever is lower.  
Operating Ratings(1)  
Supply Voltages (V+ - V)  
7V to 12V  
(2)  
Temperature Range  
40°C to +85°C  
Thermal Resistance:  
8 -Pin SOIC  
(θJC  
)
(θJA)  
60  
165  
235  
8-Pin VSSOP  
65  
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for  
which the device is intended to be functional, but specific performance is not ensured. For ensured specifications, see the Electrical  
Characteristics.  
(2) The maximum power dissipation is a function of TJ(MAX), θJA. The maximum allowable power dissipation at any ambient temperature is  
PD = (TJ(MAX) – TA)/ θJA. All numbers apply for packages soldered directly onto a PC Board.  
2
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LMH6505  
www.ti.com  
SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
Electrical Characteristics(1)  
Unless otherwise specified, all limits are ensured for TJ = 25°C, VS = ±5V, AVMAX = 9.4 V/V, RF = 1 k, RG = 100, VIN  
±0.1V, RL = 100, VG = +2V. Boldface limits apply at the temperature extremes.  
=
Symbol  
Parameter  
Conditions  
Min  
Typ  
Max  
Units  
(2)  
(3)  
(2)  
Frequency Domain Response  
BW  
GF  
3 dB Bandwidth  
VOUT < 1 VPP  
150  
38  
MHz  
MHz  
VOUT < 4 VPP, AVMAX = 100  
Gain Flatness  
VOUT < 1 VPP  
40  
0.9V VG 2V, ±0.2 dB  
Att Range Flat Band (Relative to Max Gain)  
±0.2 dB Flatness, f < 30 MHz  
±0.1 dB Flatness, f < 30 MHz  
26  
9.5  
100  
(4)  
dB  
Attenuation Range  
(5)  
BW  
Control  
Gain control Bandwidth  
Feed-through  
VG = 1V  
MHz  
CT (dB)  
VG = 0V, 30 MHz  
(Output/Input)  
51  
dB  
dB  
GR  
Gain Adjustment Range  
f < 10 MHz  
f < 30 MHz  
80  
71  
Time Domain Response  
tr, tf  
Rise and Fall Time  
0.5V Step  
2.1  
10  
ns  
%
OS %  
SR  
Overshoot  
Slew Rate  
(6)  
Non Inverting  
Inverting  
900  
1500  
V/μs  
(1) Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very  
limited self-heating of the device such that TJ = TA. No ensured specification of parametric performance is indicated in the Electrical  
Tables under conditions of internal self-heating where TJ > TA.  
(2) Limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlations using the  
Statistical Quality Control (SQC) method.  
(3) Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary  
over time and will also depend on the application and configuration. The typical values are not tested and are not ensured on shipped  
production material.  
(4) Flat Band Attenuation (Relative To Max Gain) Range Definition: Specified as the attenuation range from maximum which allows gain  
flatness specified (either ±0.2 dB or ±0.1 dB), relative to AVMAX gain. For example, for f < 30 MHz, here are the Flat Band Attenuation  
ranges:  
±0.2 dB: 19.7 dB down to -6.3 dB = 26 dB range  
±0.1 dB: 19.7 dB down to 10.2 dB = 9.5 dB range  
(5) Gain control frequency response schematic:  
R
F
1 kW  
+0.2 V  
DC  
R
OUT  
50W  
+V  
IN  
+
R
1
PORT 2  
LMH6505  
50W  
R
L
-
V
50W  
G
R
G
100W  
+5V  
-5V  
C
1
0.01 mF  
R
F
IN  
R
P1  
10 kW  
R
T
1V DC  
PORT 1  
50W  
(6) Slew rate is the average of the rising and falling slew rates.  
Copyright © 2005–2013, Texas Instruments Incorporated  
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SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
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Electrical Characteristics(1) (continued)  
Unless otherwise specified, all limits are ensured for TJ = 25°C, VS = ±5V, AVMAX = 9.4 V/V, RF = 1 k, RG = 100, VIN  
±0.1V, RL = 100, VG = +2V. Boldface limits apply at the temperature extremes.  
=
Symbol  
Parameter  
Conditions  
Min  
Typ  
Max  
Units  
(2)  
(3)  
(2)  
Distortion & Noise Performance  
HD2  
HD3  
THD  
En tot  
IN  
2nd Harmonic Distortion  
3rd Harmonic Distortion  
Total Harmonic Distortion  
Total Equivalent Input Noise  
Input Noise Current  
2VPP, 20 MHz  
47  
–61  
45  
4.4  
dBc  
f > 1 MHz, RSOURCE = 50Ω  
f > 1 MHz  
nV/Hz  
pA/Hz  
%
2.6  
DG  
Differential Gain  
f = 4.43 MHz, RL = 100Ω  
0.30  
0.15  
DP  
Differential Phase  
deg  
DC & Miscellaneous Performance  
GACCU  
G Match  
Gain Accuracy  
(See Application Information)  
VG = 2.0V  
0
+0.1/0.53  
±0.50  
+4.3/3.9  
±0.50  
dB  
0.8V < VG < 2V  
VG = 2.0V  
Gain Matching  
(See Application Information)  
dB  
0.8V < VG < 2V  
+4.2/4.0  
K
Gain Multiplier  
(See Application Information)  
0.890  
0.830  
0.940  
0.990  
1.04  
V/V  
VIN NL  
Input Voltage Range  
RG Open  
±3  
V
VIN  
I RG_MAX  
IBIAS  
L
RG = 100Ω  
±0.60  
±0.50  
±0.74  
RG Current  
Pin 3  
±6.0  
±5.0  
±7.4  
mA  
(7)  
Bias Current  
Pin 2  
0.6  
2.5  
2.6  
µA  
(8)  
TC IBIAS  
RIN  
Bias Current Drift  
Input Resistance  
Input Capacitance  
VG Bias Current  
Pin 2  
1.28  
7
nA/°C  
MΩ  
pF  
Pin 2  
Pin 2  
CIN  
2.8  
0.9  
10  
(7)  
IVG  
Pin 1, VG = 2V  
µA  
(8)  
TC IVG  
R VG  
C VG  
VG Bias Drift  
Pin 1  
pA/°C  
MΩ  
pF  
VG Input Resistance  
VG Input Capacitance  
Output Voltage Range  
Pin 1  
25  
Pin 1  
2.8  
±2.4  
VOUT  
L
RL = 100Ω  
±2.1  
±1.9  
V
VOUT NL  
ROUT  
RL = Open  
±3.1  
0.12  
±80  
Output Impedance  
Output Current  
DC  
IOUT  
VOUT = ±4V from Rails  
±60  
mA  
±40  
VO OFFSET Output Offset Voltage  
0V < VG < 2V  
±10  
–72  
–75  
11  
±55  
±70  
mV  
dB  
+PSRR  
PSRR  
IS  
+Power Supply Rejection Ratio  
Input Referred, 1V change, VG  
2.2V  
=
=
–65  
–65  
(9)  
Power Supply Rejection Ratio  
Input Referred, 1V change, VG  
2.2V  
dB  
(9)  
Supply Current  
No Load  
9.5  
7.5  
14  
16  
mA  
(7) Positive current corresponds to current flowing into the device.  
(8) Drift is determined by dividing the change in parameter distribution at temperature extremes by the total temperature change.  
(9) +PSRR definition: [|ΔVOUT/ΔV+| / AV], PSRR definition: [|ΔVOUT/ΔV| / AV] with 0.1V input voltage. ΔVOUT is the change in output  
voltage with offset shift subtracted out.  
4
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SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
Connection Diagram  
+
1
2
3
4
8
V
V
G
7
6
5
-
I
V
R
IN  
X1  
V
G
OUT  
-
+
V-  
GND  
Figure 3. 8-Pin SOIC/VSSOP Top View  
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Typical Performance Characteristics  
Unless otherwise specified: VS = ±5V, TA = 25°C, VG = VGMAX, RF = 1 k, RG = 100, VIN = 0.1V, input terminated in 50. RL  
= 100, Typical values.  
Frequency Response Over Temperature  
Frequency Response for Various VG  
150  
150  
1
0
1
0
V
= 2V  
85°C  
G
GAIN  
GAIN  
V
G
= 1V  
100  
100  
50  
25°C  
50  
V
= 0.7V  
G
-1  
-2  
-3  
-4  
-5  
-6  
-7  
-8  
-9  
-1  
-2  
-3  
-4  
-5  
-6  
-7  
-8  
-9  
-40°C  
V
= 0.9V  
G
0
-50  
-100  
0
PHASE  
PHASE  
-50  
85°C  
-100  
-150  
-200  
-250  
-300  
-350  
25°C  
-150  
-40°C  
-200  
V
= 0.7V  
= 0.9V  
G
V
G
= 2V  
V
G
-250  
-300  
P
= -22 dBm  
P
= -22 dBm  
IN  
IN  
V
= 1V  
G
-350  
1M  
100M  
10M  
FREQUENCY (Hz)  
1G  
1M  
100M  
10M  
FREQUENCY (Hz)  
1G  
Gain/Phase normalized to low frequency value at 25°C.  
Gain/Phase normalized to low frequency value at each setting.  
Figure 4.  
Figure 5.  
Frequency Response (AVMAX = 2)  
Inverting Frequency Response  
50  
3
2
1
0
40  
V
= 1V  
G
0
GAIN  
0
GAIN  
-1  
-2  
-3  
-4  
-5  
-6  
-7  
-8  
-9  
-40  
-50  
-100  
-150  
1
V = 2V  
G
-80  
0
2 V  
PP  
V
= 0.8V  
G
-120  
-160  
-200  
-240  
-280  
-320  
-360  
-1  
4 V  
PP  
PHASE  
-200  
-250  
-300  
-350  
-400  
-2  
-3  
-4  
-5  
-6  
1 V  
PP  
PHASE  
A
= 2V/V  
VMAX  
V
G
= 0.8V  
R
R
= 1 kW  
F
V
= 1V  
= 510W  
G
G
IN  
4 V  
PP  
2 V  
PP  
P
= 4 dBm  
V
= 2V  
G
1 V  
PP  
0
0
f (50 MHz/DIV)  
f (50 MHz/DIV)  
Gain/Phase normalized to low frequency value at each setting.  
Figure 6.  
Figure 7.  
Frequency Response for Various VG (AVMAX = 100)  
(Large Signal)  
Frequency Response for Various Amplitudes  
1
2
80  
40  
0
50  
GAIN  
GAIN  
1 V  
0
PP  
0
0
-2  
0.8V  
-50  
-1  
1V  
-100  
-150  
-200  
-250  
-300  
-350  
-2  
-3  
-4  
-4  
-40  
PHASE  
-80  
-6  
PHASE  
2V  
4 V  
PP  
-120  
-8  
A
= 100V/V  
VMAX  
-5  
-10  
-12  
-14  
-160  
R
F
= 2.32 kW  
2 V  
PP  
R
= 18W  
G
IN  
-6  
-7  
-200  
-240  
P
= -24 dBm,  
0
0
f (10 MHz/DIV)  
f (20 MHz/DIV)  
Gain/Phase normalized to low frequency value at each setting.  
Gain/Phase normalized to low frequency value at each setting.  
Figure 8.  
Figure 9.  
6
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Typical Performance Characteristics (continued)  
Unless otherwise specified: VS = ±5V, TA = 25°C, VG = VGMAX, RF = 1 k, RG = 100, VIN = 0.1V, input terminated in 50. RL  
= 100, Typical values.  
Gain Control Frequency Response  
IS vs. VS  
15  
10  
5
120  
20  
18  
16  
14  
12  
10  
8
40°C  
MAGNITUDE  
V
= V  
G_MIN  
G
R
80  
40  
= OPEN  
L
85°C  
25°C  
0
0
85°C  
ANGLE  
-40  
-5  
40°C  
25°C  
85°C  
-10  
-15  
-20  
-25  
-80  
-120  
-160  
-200  
-240  
-280  
-320  
25°C  
6
V
V
V
(AC) = -13.7 dBm  
G
IN  
G
-40°C  
-30  
4
= 0.2V (DC)  
-35  
-40  
= 0.98 AVERAGE  
2
0
10M  
1M  
100M  
1G  
100k  
3
3.5  
4
4.5  
5
5.5  
6
FREQUENCY (Hz)  
±SUPPLY VOTLAGE (V)  
See Electrical Characteristics Note (5).  
Figure 10.  
Figure 11.  
IS vs. VS  
Input Bias Current vs. VS  
-0.4  
-0.5  
20  
18  
16  
14  
12  
10  
8
R
= OPEN  
L
85°C  
85°C  
25°C  
-0.6  
-0.7  
-0.8  
25°C  
6
-40°C  
4
-40°C  
2
0
2
3
4
5
6
3
3.5  
4
4.5  
5
5.5  
6
±SUPPLY VOLTAGE (V)  
±SUPPLY VOTLAGE (V)  
Figure 12.  
Figure 13.  
PSRR  
AVMAX vs. Supply Voltage  
0
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
12  
10  
8
85°C  
25°C  
-40°C  
-PSRR  
6
4
+PSRR  
10M  
2
0
100  
10k 100k  
1M  
100M  
1k  
2.5  
3
3.5  
4
4.5  
5
5.5  
6
FREQUENCY (Hz)  
±SUPPLY VOLTAGE  
See Electrical Characteristics Note (9)  
Figure 14.  
Figure 15.  
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Typical Performance Characteristics (continued)  
Unless otherwise specified: VS = ±5V, TA = 25°C, VG = VGMAX, RF = 1 k, RG = 100, VIN = 0.1V, input terminated in 50. RL  
= 100, Typical values.  
Feed through Isolation for Various AVMAX  
60  
Gain Variation Over entire Temp Range vs. VG  
100  
TEMP RANGE: -55°C TO 125°C  
|GAIN(COLD) œ GAIN (HOT)  
40  
20  
10  
0
A
= 100 V/V  
= 10 V/V  
= 2 V/V  
VMAX  
1
0.1  
-20  
-40  
-60  
-80  
-100  
A
A
VMAX  
VMAX  
0.01  
0
0.5  
1
1.5  
2
100k  
1M  
10M  
100M  
1G  
V
(V)  
G
FREQUENCY (Hz)  
Figure 16.  
Figure 17.  
IRG vs. VIN  
Gain vs. VG  
-10  
-8  
30  
10  
12  
11  
10  
9
-6  
125°C  
-4  
-10  
-30  
-50  
-70  
-90  
8
7
25°C  
-2  
0
-55°C  
dB  
6
5
125°C  
V/V  
+2  
+4  
+6  
+8  
4
3
2
1
25°C  
-55°C  
0
-0.5  
-0.5  
0
0.5  
1
1.5  
-1.5  
-1  
0
0.5  
1
1.5  
2
V
(V)  
V (V)  
G
IN  
See Electrical Characteristics Note (7).  
Figure 18.  
Figure 19.  
Output Offset Voltage vs. VG (Typical Unit #1)  
Output Offset Voltage vs. VG (Typical Unit #2)  
10  
30  
25°C  
-40°C  
25  
5
85°C  
20  
0
15  
25°C  
-5  
10  
85°C  
85°C  
-10  
5
-40°C  
-15  
0
1
0
0.5  
1
1.5  
(V)  
2
2.5  
0
0.5  
1.5  
(V)  
2
2.5  
V
V
G
G
Figure 20.  
Figure 21.  
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Typical Performance Characteristics (continued)  
Unless otherwise specified: VS = ±5V, TA = 25°C, VG = VGMAX, RF = 1 k, RG = 100, VIN = 0.1V, input terminated in 50. RL  
= 100, Typical values.  
Output Offset Voltage vs. VG (Typical Unit #3)  
Distribution of Output Offset Voltage  
24  
22  
20  
30  
25°C  
25  
20  
18  
16  
14  
12  
10  
8
15  
-40°C  
10  
85°C  
6
4
2
5
25°C  
0
0
-55  
-45  
-15 -5  
5
35 45  
15 25 55  
-35 -25  
0
0.5  
1
1.5  
(V)  
2
2.5  
OFFSET VOLTAGE (mV)  
V
G
Figure 22.  
Output Noise Density vs. Frequency  
Figure 23.  
Output Noise Density vs. Frequency  
10000  
1000  
100  
100000  
10000  
1000  
100  
R
- 50W  
SOURCE  
A
= 100  
VMAX  
R
R
R
= 2.4 kW  
F
= 22W  
G
V
G_MAX  
= 50W  
SOURCE  
V
G_MAX  
V
V
G_MID  
G_MID  
V
G_MIN  
V
G_MIN  
100  
10  
10  
1
1M 10M  
10  
1k 10k 100k  
100  
1
1M 10M  
10  
1k 10k 100k  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 24.  
Figure 25.  
Output Noise Density vs. Frequency  
Input Referred Noise Density vs. Frequency  
10000  
1000  
100  
1000  
100  
10  
1000  
A
= 2  
VMAX  
R
= 510W  
G
R
= 50W  
SOURCE  
V
G_MAX  
100  
10  
1
VOLTAGE  
V
G_MID  
V
G_MIN  
CURRENT  
10  
1
1
10 100 1k 10k 100k  
FREQUENCY (Hz)  
Figure 26.  
10M  
1
10 100 1k 10k 100k  
FREQUENCY (Hz)  
Figure 27.  
10M  
1M  
1M  
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Typical Performance Characteristics (continued)  
Unless otherwise specified: VS = ±5V, TA = 25°C, VG = VGMAX, RF = 1 k, RG = 100, VIN = 0.1V, input terminated in 50. RL  
= 100, Typical values.  
Output Voltage vs. Output Current (Sinking)  
Output Voltage vs. Output Current (Sourcing)  
5
5
25°C  
85°C  
-40°C  
-40°C  
85°C  
25°C  
4
4
3
2
1
0
3
2
1
0
-40°C  
-40°C  
25°C  
85°C  
85°C  
0
20  
40  
60  
(mA)  
80  
100  
120  
0
20  
40  
60  
80  
100  
120  
I
I
(mA)  
OUT  
OUT  
Figure 28.  
Distortion vs. Frequency  
Figure 29.  
HD vs. POUT  
-120  
-110  
-100  
-90  
-30  
V
G
= V  
V
V
= V  
G_MAX  
GMAX  
G
HD3, 100 kHz  
= 1 V  
OUT  
PP  
-40  
-50  
HD2, 100 kHz  
-80  
-60  
-70  
-70  
THD  
-60  
HD2  
HD3  
-50  
-80  
HD2, 20 MHz  
-40  
HD3, 20 MHz  
-90  
-30  
-20  
-100  
-10  
-5  
0
5
10  
15  
20  
100k  
1M  
10M  
100M  
FREQUENCY (Hz)  
P
(dBm)  
OUT  
Figure 30.  
Figure 31.  
THD vs. POUT  
THD vs. POUT  
-70  
-60  
-50  
-100  
V
G
= V  
G_MAX  
-90  
-80  
-70  
-60  
-50  
-40  
-30  
-20  
1 MHz  
20 MHz  
-40  
100 kHz  
20 MHz  
-30  
-20  
-10  
0
V
= V  
= ~1V  
G
GMID  
-10  
-5  
0
10  
15  
20  
5
-10  
-5  
0
10  
15  
20  
5
POUT (dBm)  
P
(dBm)  
OUT  
Figure 32.  
Figure 33.  
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Typical Performance Characteristics (continued)  
Unless otherwise specified: VS = ±5V, TA = 25°C, VG = VGMAX, RF = 1 k, RG = 100, VIN = 0.1V, input terminated in 50. RL  
= 100, Typical values.  
THD vs. Gain  
= 0.25 V  
100 kHz  
THD vs. Gain  
-90  
-80  
-70  
-60  
-50  
-40  
-30  
-20  
-10  
0
-80  
-70  
-60  
-50  
-40  
-30  
-20  
-10  
V
V
100 kHz  
OUT  
VARIED  
PP  
V
V
= 1 V  
PP  
OUT  
G
VARIED  
G
2 MHz  
2 MHz  
20 MHz  
20 MHz  
0
-15 -10  
-5  
0
5
10  
15  
20  
-5  
0
5
10  
15  
20  
GAIN (dB)  
GAIN (dB)  
Figure 34.  
Figure 35.  
Differential Gain & Phase  
f = 4.43 MHz  
VG Bias Current vs. VG  
0.15  
0.1  
0.5  
0.4  
0.3  
0.2  
940  
920  
900  
880  
860  
840  
820  
R
= 100W  
L
V
= V  
GMAX  
G
0.05  
0
DP  
DG  
-0.05  
-0.1  
-0.15  
0.1  
0
-0.1  
-1.4 -1 -0.6 -0.2 0.2 0.6  
1
1.4  
0
0.5  
1
1.5  
(V)  
2
2.5  
3
V
DC (V)  
OUT  
V
G
Figure 36.  
Step Response Plot  
Figure 37.  
Step Response Plot  
0.5 V SMALL SIGNAL  
PP  
0.5 V SMALL SIGNAL  
PP  
SS REF  
LS REF  
SS REF  
LS REF  
4 V LARGE SIGNAL  
PP  
4 V LARGE SIGNAL  
PP  
V
G
= V  
G_MID  
5 ns/DIV  
5 ns/DIV  
Figure 38.  
Figure 39.  
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Typical Performance Characteristics (continued)  
Unless otherwise specified: VS = ±5V, TA = 25°C, VG = VGMAX, RF = 1 k, RG = 100, VIN = 0.1V, input terminated in 50. RL  
= 100, Typical values.  
Gain vs. VG Step  
2.5  
2
10  
9
GAIN  
8
7
V
G
1.5  
1
6
5
4
3
0.5  
2
1
V
= 0.3V  
IN  
0
0
t (10 ns/DIV)  
Figure 40.  
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APPLICATION INFORMATION  
GENERAL DESCRIPTION  
The key features of the LMH6505 are:  
Low power  
Broad voltage controlled gain and attenuation range (from AVMAX down to complete cutoff)  
Bandwidth independent, resistor programmable gain range (RG)  
Broad signal and gain control bandwidths  
Frequency response may be adjusted with RF  
High impedance signal and gain control inputs  
The LMH6505 combines a closed loop input buffer (“X1” Block in Figure 41), a voltage controlled variable gain  
cell (“MULT” Block) and an output amplifier (“CFA” Block). The input buffer is a transconductance stage whose  
gain is set by the gain setting resistor, RG. The output amplifier is a current feedback op amp and is configured  
as a transimpedance stage whose gain is set by, and is equal to, the feedback resistor, RF. The maximum gain,  
AVMAX, of the LMH6505 is defined by the ratio: K · RF/RG where “K” is the gain multiplier with a nominal value of  
0.940. As the gain control input (VG) changes over its 0 to 2V range, the gain is adjusted over a range of about  
80 dB relative to the maximum set gain.  
-
+
INPUT  
SIGNAL  
5V  
6.8 µF  
GAIN  
CONTROL  
0.1 µF  
+V  
CC  
V
G
MULT  
R
F
V
IN  
RX  
50W  
I-  
X1  
1 kW  
O
OUTPUT  
R
O
V
R
G
R
IN  
50W  
50W  
-
-V  
CC  
CFA  
GND  
+
R
G
-
6.8 µF  
+
100W  
0.1 µF  
-5V  
Figure 41. LMH6505 Typical Application and Block Diagram  
SETTING THE LMH6505 MAXIMUM GAIN  
RF  
RG  
AVMAX  
=
· K  
(1)  
Although the LMH6505 is specified at AVMAX = 9.4 V/V, the recommended AVMAX varies between 2 and 100.  
Higher gains are possible but usually impractical due to output offsets, noise and distortion. When varying AVMAX  
several tradeoffs are made:  
RG: determines the input voltage range  
RF: determines overall bandwidth  
The amount of current which the input buffer can source/sink into RG is limited and is given in the IRG_MAX  
specification. This sets the maximum input voltage:  
VIN (MAX) = IRG  
· RG  
MAX  
(2)  
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As the IRG_MAX limit is approached with increasing the input voltage or with the lowering of RG, the device's  
harmonic distortion will increase. Changes in RF will have a dramatic effect on the small signal bandwidth. The  
output amplifier of the LMH6505 is a current feedback amplifier (CFA) and its bandwidth is determined by RF. As  
with any CFA, doubling the feedback resistor will roughly cut the bandwidth of the device in half.  
For more about CFAs, see the basic tutorial, OA-20, Current Feedback Myths Debunked, (literature number  
SNOA376), or a more rigorous analysis, OA-13, Current Feedback Amplifier Loop Gain Analysis and  
Performance Enhancements, (literature number SNOA366).  
OTHER CONFIGURATIONS  
1. Single Supply Operation  
The LMH6505 can be configured for use in a single supply environment. Doing so requires the following:  
(a) Bias pin 4 and RG to a “virtual half supply” somewhere close to the middle of V+ and Vrange. The other  
end of RG is tied to pin 3. The “virtual half supply” needs to be capable of sinking and sourcing the  
expected current flow through RG.  
(b) Ensure that VG can be adjusted from 0V to 2V above the “virtual half supply”.  
(c) Bias the input (pin 2) to make sure that it stays within the range of 2V above Vto 2V below V+. See the  
Input Voltage Range specification in the Electrical Characteristics table. This can be accomplished by  
either DC biasing the input and AC coupling the input signal, or alternatively, by direct coupling if the  
output of the driving stage is also biased to half supply.  
Arranged this way, the LMH6505 will respond to the current flowing through RG. The gain control relationship  
will be similar to the split supply arrangement with VG measured with reference to pin 4. Keep in mind that  
the circuit described above will also center the output voltage to the “virtual half supply voltage.”  
2. Arbitrarily Referenced Input Signal  
Having a wide input voltage range on the input (pin 2) (±3V typical), the LMH6505 can be configured to  
control the gain on signals which are not referenced to ground (e.g. Half Supply biased circuits). This node  
will be called the “reference node”. In such cases, the other end of RG which is the side not tied to pin 3 can  
be tied to this reference node so that RG will “look at” the difference between the signal and this reference  
only. Keep in mind that the reference node needs to source and sink the current flowing through RG.  
GAIN ACCURACY  
Gain accuracy is defined as the actual gain compared against the theoretical gain at a certain VG, the results of  
which are expressed in dB. (See Figure 42).  
Theoretical gain is given by:  
RF  
1
x
x
A(V/V) = K  
RG  
N - VG  
VC  
1 + e  
where  
K = 0.940 (nominal) N = 1.01V  
VC = 79 mV at room temperature  
(3)  
For a VG range, the value specified in the tables represents the worst case accuracy over the entire range. The  
"Typical" value would be the difference between the "Typical Gain" and the "Theoretical Gain." The "Max" value  
would be the worst case difference between the actual gain and the "Theoretical Gain" for the entire population.  
GAIN MATCHING  
As Figure 42 shows, gain matching is the limit on gain variation at a certain VG, expressed in dB, and is specified  
as "±Max" only. There is no "Typical." For a VG range, the value specified represents the worst case matching  
over the entire range. The "Max" value would be the worst case difference between the actual gain and the  
typical gain for the entire population.  
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MAX GAIN LIMIT  
THEORETICAL GAIN  
MIN GAIN LIMIT  
D
C
TYPICAL GAIN  
PARAMETER:  
B
A
GAIN ACCURACY (TYPICAL) = B-C  
GAIN ACCURACY (+MAX) = D-C  
GAIN ACCURACY (-MAX) = A-C  
GAIN MATCHING (+MAX) = D-B  
GAIN MATCHING (-MAX) = A-B  
V
(V)  
G
Figure 42. LMH6505 Gain Accuracy & Gain Matching Defined  
GAIN PARTITIONING  
If high levels of gain are needed, gain partitioning should be considered:  
V
G
V
IN  
1
+
25W  
2
3
LMH6624  
6
R
C
V
LMH6505  
O
-
7
4
R
2
R
F
R
G
R
1
Figure 43. Gain Partitioning  
The maximum gain range for this circuit is given by the following equation:  
R2  
R1  
RF  
RG  
MAXIMUM GAIN =  
K
1 +  
·
·
(4)  
The LMH6624 is a low noise wideband voltage feedback amplifier. Setting R2 at 909and R1 at 100produces  
a gain of 20 dB. Setting RF at 1000as recommended and RG at 50, produces a gain of about 26 dB in the  
LMH6505. The total gain of this circuit is therefore approximately 46 dB. It is important to understand that when  
partitioning to obtain high levels of gain, very small signal levels will drive the amplifiers to full scale output. For  
example, with 46 dB of gain, a 20 mV signal at the input will drive the output of the LMH6624 to 200 mV and the  
output of the LMH6505 to 4V. Accordingly, the designer must carefully consider the contributions of each stage  
to the overall characteristics. Through gain partitioning the designer is provided with an opportunity to optimize  
the frequency response, noise, distortion, settling time, and loading effects of each amplifier to achieve improved  
overall performance.  
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LMH6505 GAIN CONTROL RANGE AND MINIMUM GAIN  
Before discussing Gain Control Range, it is important to understand the issues which limit it. The minimum gain  
of the LMH6505 is theoretically zero, but in practical circuits it is limited by the amount of feedthrough, here  
defined as the gain when VG = 0V. Capacitive coupling through the board and package, as well as coupling  
through the supplies, will determine the amount of feedthrough. Even at DC, the input signal will not be  
completely rejected. At high frequencies feedthrough will get worse because of its capacitive nature. At  
frequencies below 10 MHz, the feed through will be less than 60 dB and therefore, it can be said that with  
AVMAX = 20 dB, the gain control range is 80 dB.  
LMH6505 GAIN CONTROL FUNCTION  
In the plot, Gain vs. VG (Figure 19), we can see the gain as a function of the control voltage. The “Gain (V/V)”  
plot, sometimes referred to as the S-curve, is the linear (V/V) gain. This is a hyperbolic tangent relationship and  
is given by Equation 3. The “Gain (dB)” plots the gain in dB and is linear over a wide range of gains. Because of  
this, the LMH6505 gain control is referred to as “linear-in-dB.”  
For applications where the LMH6505 will be used at the heart of a closed loop AGC circuit, the S-curve control  
characteristic provides a broad linear (in dB) control range with soft limiting at the highest gains where large  
changes in control voltage result in small changes in gain. For applications requiring a fully linear (in dB) control  
characteristic, use the LMH6505 at half gain and below (VG 1V).  
GAIN STABILITY  
The LMH6505 architecture allows complete attenuation of the output signal from full gain to complete cutoff. This  
is achieved by having the gain control signal VG “throttle” the signal which gets through to the final stage and  
which results in the output signal. As a consequence, the RG pin's (pin 3) average current (DC current) influences  
the operating point of this “throttle” circuit and affects the LMH6505's gain slightly. Figure 44 below, shows this  
effect as a function of the gain set by VG.  
4.5  
4
3.5  
3
4.5 mA SOURCING  
2.5  
2
1.5  
1
4.5 mA SINKING  
0.5  
0
-0.5  
-80  
-60  
-40  
-20  
(dB)  
0
20  
A
V
Figure 44. LMH6505 Gain Variation over RG DC Current Capability vs. Gain  
This plot shows the expected gain variation for the maximum RG DC current capability (±4.5 mA). For example,  
with gain (AV) set to 60 dB, if the RG pin DC current is increased to 4.5 mA sourcing, one would expect to see  
the gain increase by about 3 dB (to 57 dB). Conversely, 4.5 mA DC sinking current through RG would increase  
gain by 1.75 dB (to 58.25 dB). As you can see from Figure 44 above, the effect is most pronounced with  
reduced gain and is limited to less than 3.75 dB variation maximum.  
If the application is expected to experience RG DC current variation and the LMH6505 gain variation is beyond  
acceptable limits, please refer to the LMH6502 (Differential Linear in dB variable gain amplifier) datasheet  
instead at http://www.ti.com/lit/gpn/LMH6502.  
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AVOIDING OVERDRIVE OF THE LMH6505 GAIN CONTROL INPUT  
There is an additional requirement for the LMH6505 Gain Control Input (VG): VG must not exceed +2.3V (with  
±5V supplies). The gain control circuitry may saturate and the gain may actually be reduced. In applications  
where VG is being driven from a DAC, this can easily be addressed in the software. If there is a linear loop  
driving VG, such as an AGC loop, other methods of limiting the input voltage should be implemented. One simple  
solution is to place a 2.2:1 resistive divider on the VG input. If the device driving this divider is operating off of  
±5V supplies as well, its output will not exceed 5V and through the divider VG can not exceed 2.3V.  
IMPROVING THE LMH6505 LARGE SIGNAL PERFORMANCE  
Figure 45 illustrates an inverting gain scheme for the LMH6505.  
V
G
1
2
3
6
V
O
LMH6505  
25W  
V
IN  
7
4
R
G
R
F
Figure 45. Inverting Amplifier  
The input signal is applied through the RG resistor. The VIN pin should be grounded through a 25resistor. The  
maximum gain range of this configuration is given in the following equation:  
RF  
-
=
·K  
AVMAX  
RG  
(5)  
The inverting slew rate of the LMH6505 is much higher than that of the non-inverting slew rate. This 2X  
performance improvement comes about because in the non-inverting configuration the slew rate of the overall  
amplifier is limited by the input buffer. In the inverting circuit, the input buffer remains at a fixed voltage and does  
not affect slew rate.  
TRANSMISSION LINE MATCHING  
One method for matching the characteristic impedance of a transmission line is to place the appropriate resistor  
at the input or output of the amplifier. Figure 46 shows a typical circuit configuration for matching transmission  
lines.  
V
G
C
O
Z
O
1
2
3
Z
O
6
R
S
OUTPUT  
LMH6505  
R
I
SIGNAL  
INPUT  
+
R
O
7
-
R
T
4
R
G
R
F
Figure 46. Transmission Line Matching  
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The resistors RS, RI, RO, and RT are equal to the characteristic impedance, ZO, of the transmission line or cable.  
Use CO to match the output transmission line over a greater frequency range. It compensates for the increase of  
the op amp’s output impedance with frequency.  
MINIMIZING PARASITIC EFFECTS ON SMALL SIGNAL BANDWIDTH  
The best way to minimize parasitic effects is to use surface mount components and to minimize lead lengths and  
component distance from the LMH6505. For designs utilizing through-hole components, specifically axial  
resistors, resistor self-capacitance should be considered. For example, the average magnitude of parasitic  
capacitance of RN55D 1% metal film resistors is about 0.15 pF with variations of as much as 0.1 pF between  
lots. Given the LMH6505’s extended bandwidth, these small parasitic reactance variations can cause  
measurable frequency response variations in the highest octave. We therefore recommend the use of surface  
mount resistors to minimize these parasitic reactance effects.  
RECOMMENDATIONS  
Here are some recommendations to avoid problems and to get the best performance:  
Do not place a capacitor across RF. However, an appropriately chosen series RC combination can be used to  
shape the frequency response.  
Keep traces connecting RF separated and as short as possible.  
Place a small resistor (20-50) between the output and CL.  
Cut away the ground plane, if any, under RG.  
Keep decoupling capacitors as close as possible to the LMH6505.  
Connect pin 2 through a minimum resistance of 25.  
ADJUSTING OFFSETS AND DC LEVEL SHIFTING  
Offsets can be broken into two parts: an input-referred term and an output-referred term. These errors can be  
trimmed using the circuit in Figure 47. First set VG to 0V and adjust the trim pot R4 to null the offset voltage at the  
output. This will eliminate the output stage offsets. Next set VG to 2V and adjust the trim pot R1 to null the offset  
voltage at the output. This will eliminate the input stage offsets.  
V
G
1
2
3
V
IN  
6
V
O
LMH6505  
R
F
7
+5V  
-5V  
4
R
10 kW  
2
+5V  
-5V  
R
G
R
10 kW  
R
1
3
10 kW  
R
10 kW  
4
0.1 µF  
0.1 µF  
Figure 47. Offset Adjust Circuit  
DIGITAL GAIN CONTROL  
Digitally variable gain control can be easily realized by driving the LMH6505 gain control input with a digital-to-  
analog converter (DAC). Figure 48 illustrates such an application. This circuit employs TI’s eight-bit DAC0830,  
the LMC8101 MOS input op amp (Rail-to-Rail Input/Output), and the LMH6505 VGA. With VREF set to 2V, the  
circuit provides up to 80 dB of gain control in 256 steps with up to 0.05% full scale resolution. The maximum gain  
of this circuit is 20 dB.  
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DIGITAL  
INPUT  
R
FB  
I
I
o1  
-
V
REF  
LMC8101  
DAC0830  
+
1
2
3
o2  
V
IN  
V
O
6
LMH6505  
7
4
R
G
100W  
R
F
1 kW  
Figure 48. Digital Gain Control  
USING THE LMH6505 IN AGC APPLICATIONS  
In AGC applications, the control loop forces the LMH6505 to have a fixed output amplitude. The input amplitude  
will vary over a wide range and this can be the issue that limits dynamic range. At high input amplitudes, the  
distortion due to the input buffer driving RG may exceed that which is produced by the output amplifier driving the  
load. In the plot, THD vs. Gain, total harmonic distortion (THD) is plotted over a gain range of nearly 35 dB for a  
fixed output amplitude of 0.25 VPP in the specified configuration, RF = 1 k, RG = 100. When the gain is  
adjusted to 15 dB (i.e. 35 dB down from AVMAX), the input amplitude would be 1.41 VPP and we can see the  
distortion is at its worst at this gain. If the output amplitude of the AGC were to be raised above 0.25 VPP, the  
input amplitudes for gains 40 dB down from AVMAX would be even higher and the distortion would degrade  
further. It is for this reason that we recommend lower output amplitudes if wide gain ranges are desired. Using a  
post-amp like the LMH6714/LMH6720/LMH6722 family or the LMH6702 would be the best way to preserve  
dynamic range and yield output amplitudes much higher than 100 mVPP. Another way of addressing distortion  
performance and its limitations on dynamic range, would be to raise the value of RG. Just like any other high-  
speed amplifier, by increasing the load resistance, and therefore decreasing the demanded load current, the  
distortion performance will be improved in most cases. With an increased RG, RF will also have to be increased  
to keep the same AVMAX and this will decrease the overall bandwidth. It may be possible to insert a series RC  
combination across RF in order to counteract the negative effect on BW when a large RF is used.  
AUTOMATIC GAIN CONTROL (AGC)  
Fast Response AGC Loop  
The AGC circuit shown in Figure 49 will correct a 6 dB input amplitude step in 100 ns. The circuit includes a two  
op amp precision rectifier amplitude detector (U1 and U2), and an integrator (U3) to provide high loop gain at low  
frequencies. The output amplitude is set by R9. The following are some suggestions for building fast AGC loops:  
Precision rectifiers work best with large output signals. Accuracy is improved by blocking DC offsets, as shown in  
Figure 49.  
Copyright © 2005–2013, Texas Instruments Incorporated  
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19  
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LMH6505  
SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
www.ti.com  
INCLUDES SCOPE  
PROBE CAPACITANCE  
1
C
3
2
3
V
IN  
40 pF  
+
OUTPUT  
20 MHz,  
U4  
LMH6505  
6
0.1 V  
PP  
-
7
C
1
R
F
R
10  
500W  
4
1.0 µF  
R
G
100W  
R
1
C
2
20W  
680 pF  
R
5
R
3
25W  
300W  
R
8
+
500W  
U2  
LMH6714  
-
U3  
LMH6609  
-
R
R
4
6
+
R
9
300W  
300W  
4.22 kW  
-
U1  
LMH6714  
R
7
1N5712  
SCHOTTKY  
300W  
+
-5V  
R
2
25W  
Figure 49. Automatic Gain Control Circuit  
Signal frequencies must not reach the gain control port of the LMH6505, or the output signal will be distorted  
(modulated by itself). A fast settling AGC needs additional filtering beyond the integrator stage to block signal  
frequencies. This is provided in Figure 49 by a simple R-C filter (R10 and C3); better distortion performance can  
be achieved with a more complex filter. These filters should be scaled with the input signal frequency. Loops with  
slower response time, which means longer integration time constants, may not need the R10 – C3 filter.  
Checking the loop stability can be done by monitoring the VG voltage while applying a step change in input signal  
amplitude. Changing the input signal amplitude can be easily done with an arbitrary waveform generator.  
20  
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Copyright © 2005–2013, Texas Instruments Incorporated  
Product Folder Links: LMH6505  
 
LMH6505  
www.ti.com  
SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
CIRCUIT LAYOUT CONSIDERATIONS & EVALUATION BOARDS  
A good high frequency PCB layout including ground plane construction and power supply bypassing close to the  
package is critical to achieving full performance. The amplifier is sensitive to stray capacitance to ground at the I-  
input (pin 7) so it is best to keep the node trace area small. Shunt capacitance across the feedback resistor  
should not be used to compensate for this effect. Capacitance to ground should be minimized by removing the  
ground plane from under the body of RG. Parasitic or load capacitance directly on the output (pin 6) degrades  
phase margin leading to frequency response peaking.  
The LMH6505 is fully stable when driving a 100load. With reduced load (e.g. 1k.) there is a possibility of  
instability at very high frequencies beyond 400 MHz especially with a capacitive load. When the LMH6505 is  
connected to a light load as such, it is recommended to add a snubber network to the output (e.g. 100and 39  
pF in series tied between the LMH6505 output and ground). CL can also be isolated from the output by placing a  
small resistor in series with the output (pin 6).  
Component parasitics also influence high frequency results. Therefore it is recommended to use metal film  
resistors such as RN55D or leadless components such as surface mount devices. High profile sockets are not  
recommended.  
Texas Instruments suggests the following evaluation board as a guide for high frequency layout and as an aid in  
device testing and characterization:  
Device  
Package  
Evaluation Board  
Part Number  
LMH6505  
SOIC  
LMH730066  
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SNOSAT4E DECEMBER 2005REVISED APRIL 2013  
www.ti.com  
REVISION HISTORY  
Changes from Revision D (April 2013) to Revision E  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 21  
22  
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Copyright © 2005–2013, Texas Instruments Incorporated  
Product Folder Links: LMH6505  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LMH6505MA/NOPB  
LMH6505MAX/NOPB  
LMH6505MM/NOPB  
ACTIVE  
SOIC  
SOIC  
D
D
8
8
8
95  
RoHS & Green  
SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
-40 to 85  
-40 to 85  
-40 to 85  
LMH65  
05MA  
ACTIVE  
ACTIVE  
2500 RoHS & Green  
1000 RoHS & Green  
SN  
SN  
LMH65  
05MA  
VSSOP  
DGK  
AZ2A  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
5-Jan-2022  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LMH6505MAX/NOPB  
LMH6505MM/NOPB  
SOIC  
D
8
8
2500  
1000  
330.0  
178.0  
12.4  
12.4  
6.5  
5.3  
5.4  
3.4  
2.0  
1.4  
8.0  
8.0  
12.0  
12.0  
Q1  
Q1  
VSSOP  
DGK  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
5-Jan-2022  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LMH6505MAX/NOPB  
LMH6505MM/NOPB  
SOIC  
D
8
8
2500  
1000  
367.0  
208.0  
367.0  
191.0  
35.0  
35.0  
VSSOP  
DGK  
Pack Materials-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
5-Jan-2022  
TUBE  
*All dimensions are nominal  
Device  
Package Name Package Type  
SOIC  
Pins  
SPQ  
L (mm)  
W (mm)  
T (µm)  
B (mm)  
LMH6505MA/NOPB  
D
8
95  
495  
8
4064  
3.05  
Pack Materials-Page 3  
PACKAGE OUTLINE  
D0008A  
SOIC - 1.75 mm max height  
SCALE 2.800  
SMALL OUTLINE INTEGRATED CIRCUIT  
C
SEATING PLANE  
.228-.244 TYP  
[5.80-6.19]  
.004 [0.1] C  
A
PIN 1 ID AREA  
6X .050  
[1.27]  
8
1
2X  
.189-.197  
[4.81-5.00]  
NOTE 3  
.150  
[3.81]  
4X (0 -15 )  
4
5
8X .012-.020  
[0.31-0.51]  
B
.150-.157  
[3.81-3.98]  
NOTE 4  
.069 MAX  
[1.75]  
.010 [0.25]  
C A B  
.005-.010 TYP  
[0.13-0.25]  
4X (0 -15 )  
SEE DETAIL A  
.010  
[0.25]  
.004-.010  
[0.11-0.25]  
0 - 8  
.016-.050  
[0.41-1.27]  
DETAIL A  
TYPICAL  
(.041)  
[1.04]  
4214825/C 02/2019  
NOTES:  
1. Linear dimensions are in inches [millimeters]. Dimensions in parenthesis are for reference only. Controlling dimensions are in inches.  
Dimensioning and tolerancing per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed .006 [0.15] per side.  
4. This dimension does not include interlead flash.  
5. Reference JEDEC registration MS-012, variation AA.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
D0008A  
SOIC - 1.75 mm max height  
SMALL OUTLINE INTEGRATED CIRCUIT  
8X (.061 )  
[1.55]  
SYMM  
SEE  
DETAILS  
1
8
8X (.024)  
[0.6]  
SYMM  
(R.002 ) TYP  
[0.05]  
5
4
6X (.050 )  
[1.27]  
(.213)  
[5.4]  
LAND PATTERN EXAMPLE  
EXPOSED METAL SHOWN  
SCALE:8X  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
METAL  
EXPOSED  
METAL  
EXPOSED  
METAL  
.0028 MAX  
[0.07]  
.0028 MIN  
[0.07]  
ALL AROUND  
ALL AROUND  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
4214825/C 02/2019  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
D0008A  
SOIC - 1.75 mm max height  
SMALL OUTLINE INTEGRATED CIRCUIT  
8X (.061 )  
[1.55]  
SYMM  
1
8
8X (.024)  
[0.6]  
SYMM  
(R.002 ) TYP  
[0.05]  
5
4
6X (.050 )  
[1.27]  
(.213)  
[5.4]  
SOLDER PASTE EXAMPLE  
BASED ON .005 INCH [0.125 MM] THICK STENCIL  
SCALE:8X  
4214825/C 02/2019  
NOTES: (continued)  
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
9. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
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TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE  
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD  
PARTY INTELLECTUAL PROPERTY RIGHTS.  
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate  
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable  
standards, and any other safety, security, regulatory or other requirements.  
These resources are subject to change without notice. TI grants you permission to use these resources only for development of an  
application that uses the TI products described in the resource. Other reproduction and display of these resources is prohibited. No license  
is granted to any other TI intellectual property right or to any third party intellectual property right. TI disclaims responsibility for, and you  
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TI’s products are provided subject to TI’s Terms of Sale or other applicable terms available either on ti.com or provided in conjunction with  
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