General description

LMH Company #8482; 6503 is a kind of broadband DC coupling differential input voltage control gain level. Essence The range of gain adjustment is greater than 70db to 10MHz. The maximum gain from external components and gain settings can be reduced all the way to cutting. The power consumption is 370mW and the speed is 135MHz. The voltage control of the entire gain control of the output reference DC offset is less than 350mv voltage range. The gain matching between the equipment is 0.7DB at the maximum gain. In addition, the gain of any VG is testing and guarantee tolerance. The output current feedback operation amplifier allows high -frequency large signals (rotation rate 1800V/μs), and can also drive heavy load current (75 mAh). Differential input allows co -mode to inhibit low -level enlarged or on a relatively long -term wire. For single -ended operations, unused inputs can be easily connected to the ground (or virtual semi -supply in single power applications). Reversal or non -reversible gains can get polar or other by selecting an input. When used in a single power supply, when multi -functional applications can be further improved, the range control range is set to 1V to+1V relative to the pin 11 potential (ground pins). During a single supply operation, the grounding pin is connected to the virtual semi -power supply. The gain control pipe foot has high input impedance to simplify its input impedance driver. The gain control in the V/V range is the scope of linear gain adjustment. The maximum gain can be set at anywhere at 1V/V to 100V/V or higher. Linear (unit: DB) gain control application, see LMH6502 product introduction. LMH6503 provides parcels in SOIC-14 and Tssop-14.

Features

vs ± 5V, TA 25 ; C, RF 1K , RG 174 , RL 100 , average average AV (MAX) 10, unless there are other regulations, it is a typical value.

-3db BW 135MHz

Increase control BW 100MHz

adjustment range (typical over temperature) 70db

gain matching (limit) ± 0.7db [123

]

Conversion rate 1800V/μs

Power current (empty load) 37MA

Linear output current ± 75ma

output voltage (RL 100 ) ± 3.2V

Input voltage noise 6.6nv/

Input current noise 2.4Pa/

Thd (20MHz, RL 100 , VO 2VPP) #8722 ; 57dbc

Replace CLC522

Variable Attack

Automatic gain control

Voltage controller Filter

multiplication

Absolute maximum rated value (Note 1)

ESD tolerance: (Note 4)

Human body 2kv
]

Machine model 200V

Input current ± 10mA

vin difference ± (v+ v )

output current 120mA (Note 3 )

Power voltage (v+-v ) 12.6 volts

Input/output pin voltage v ++ 0.8V, V -0.8V

Welding information:

Infrared or convection (20 seconds) 235 ; C

Peak welding (10 seconds) 260 ; C

Storage temperature range #8722 ; 65 ; C to+150 ; C

Jacking temperature+150 ; c

working rated (Note 1)

Power voltage (V+ -V ) 5V to 12V

The temperature range 40 ; Needle SOIC 138 ; C/W 45 ; C/W

14 -needle TSSOP 160 ; C/W 51 ; C/W

Electric characteristics (Note 2 )

Unless there are other regulations, tj 25 ; c, vs ± 5V, AV (maximum value) 10, vcm 0V, RF 1K , RG 174 #8486 ;, All the guarantee limit of VIN -_Diff ± 0.1V, RL 100 , VG +1V. Black body restrictions are suitable for extreme temperatures.

Electric characteristics (Note 2) (continued)

Unless there are other regulations, otherwise, TJ 25 ; C, vs ± 5V, AV, AV, AV (Maximum value) 10, VCM 0V, RF 1K , RG 174 , all guarantee limit of VIN -_Diff ± 0.1V, RL 100 , vg +1V. Black body restrictions are suitable for extremestemperature.

Electrical characteristics (Note 2) (continued)

Note 1: Absolutely maximum rated value indicates the limit of damage to the device. The working conditions of the work are designed to play the function of the equipment, but the specific performance cannot be guaranteed. For the guarantee specifications, see the electrical characteristic table.

Note 2: The value of the electrical meter is only applicable to the factory test conditions at the specified temperature. Factory testing conditions lead to the device of TJ TA. Under the condition of internal self -heating (TJ GT; TA), no parameter performance is given in the electrical meter.

Note 3: The maximum output current (iOUT) is determined by the power consumption limit or specified value of the device, which is subject to lower.

Note 4: Human model: 1.5K series 100pf. Model: 0 , 200pf series.

Note 5: The rotation rate is the average value of the increase rate and the decline rate.

Note 6: Typical values represent the most likely parameter specifications. The number of rough numbers means that the temperature is too high.

Note 7: Positive current corresponds to the current flowing in the device.

Note 8: Use the changes in parameter distribution at extreme temperature to determine the drift by changing the total temperature.

Note 9: CMRR definition: 0.1v Differential input voltage [| #8710; vout/ #8710; vcm |/av]. #8710; Vout is a change in the output voltage after the offset.

Note 10:+PSRR definition: [| #8710; vout/ #8710; v+|/av],-PSRR definition: [| #8710; vout/ #8710; v #8722 ;/Av], the input voltage difference is 0.1V. #8710; VOUT is the offset offset of the output voltage.

Note 11: The schematic diagram of the frequency of gain control:

Note 12: gain/phase standardization to the low frequency value of each AV.

Note 13: The scope definition of flat band attenuation (relative to the maximum gain): specifies the maximum attenuation range (0.2DB or ± 0.1dB) that allows the flat degree of flatness, which is compared to the AVMAX gain. For example, for f lt; 30MHz, the following is the attenuation range of the flat band: ± 0.2db: 10V/V to 1V/V 20db range ± 0.1db: 10V/V to 4.7V/v 6.5db range

Unless there are other regulations, typical performance characteristics: vs ± 5V, 25 ; c, vg vg_max, vcm 0V, RF 1K , RG 174 , two inputs are connected at 50 # 8486;, RL 100 , typical valueThe results of the reference device output:

Unless there are other regulations, typical performance characteristics: vs ± 5V, 25 ; c, vg vg_max, VCM input, VCM input The end connection is 1K , all of which are 0 , the reference value is 100 , RL 50 Output: (continued)

Unless there are other regulations, typical performance characteristics: vs ± 5V, 25 ; c, vg vg_max, and VCM input terminals are 1K , all 0 , the reference value is 100 #8486 ; RL 50 Output: (continued)

Application information Operation theory

LMH6503 is a linear broadband The variable -increasing blee is shown in Figure 1. The difference between two inputs (+vin, vin) can be applied to the voltage input signal, or it exists alone by grounding one of the two unused inputs. This LMH6503 input buffer converts the input voltage to current (IRG) is a function of a differential input voltage (VINPUT) (+VIN)-( VIN)) and the value of the resistance (RG). The current (IRG) was subsequently mirror to the gain -level current gain to K (nominal value of 1.72). Voltage control two -elephant limited multiplication method attenuation This current turns through the output amplifier and converts to voltage. This output amplifier is a current feedback computing amplifier, configured as a transmissile amplifier. Its transgender gain is the feedback resistor (RF). Input signals, output and gain control are voltage. The output voltage is easy to calculate by 1:

Therefore, the gain of LMH6503 is a function external variable: RG, RF, and VG, the second chapter of the equal formula chapter 2 :

The ideal input range of the gain control voltage (VG) is 1V LT; vg LT;+1V. When VG +1V, the gain of the LMH6503 is the maximum value as shown in Formula 3:

Note that the equivalent 3 applies to differential and single -end operations at the same time.

Select RF and RG RG calculated based on Formula 4. VINPUTMAX is the largest peak

Input voltage (VPK) determined by the application. IRGMAX is often 2.3 mAh through RG's maximum allowable current. Once you determine the AVMAX and the expected output voltage RF according to the minimum input, then use Formula 5Essence These values of RF and RG are

Meet the input voltage and maximum gain limit. Adjusting the resistance value will reduce bandwidth and improve stability. Figure 2 illustrates the generated LMH6503 bandwidth as the maximum (Y axis) and minimum values (related to X).) When Vout maintains constant input voltage at 1VPP.

Adjust the offset

The processing process of the offset LMH6503 that is processed by input and output is completed in two steps. The output -level offset voltage is first applied on the VG to the core of 1.1V, which effectively separates the core of the input and output level. As shown in Figure 3, the LMH6503 Evaluation Committee (CLC730033) should be adjusted to make the output (pin 10) at LMH6503.

Once this is completed, the offset error and then process the input level and the core of the multiplication. This second step requires the input signal and matching the source impedance on the two input pins to eliminate the bias current error. After completion,+1.1V should apply to the fine -tuning tank of VG and R10, and adjust the bias voltage of the LMH6503 output end to zero. If the expected gain range is more limited, the above -mentioned adjustment should be made at these operating points. These steps will minimize the output offset voltage. However, since the compensation itself changes with the gain setting, correction is not perfect, and there will be some remaining output offset. The gain accuracy is defined as the optimal ratio (V/V) that measures at a specific VG, and the best fit line drawn through typical gain (V/V)

-1v lt; vg lt; 1V distribution (result is based on the results of the distribution DB said) (see Figure 4). The best fitting gain (AV) is concluded by the following formulas: average (V/V) 4.87VG+4.61 (6) for: 1V ≤VG ≤+1V, RF 1K , RG 174 For VG range, the value specified in the table represents the worst accuracy of the entire range. The typical value will be the typical gain and the best fit. The maximum value is the worst case between the maximum/minimum gain restriction and the best fit. 123]

Definition as a limitation of gain change when a VG (EX presses DB) (see Figure 4). It is only specified as maximum value (whether typical ). The worst situation in the range. The worst situation ratio and typical income between the maximum value of the maximum value and minimum gain limit.

Application information (continued) [continued) 123]

Noise

FIG. 5 describes the function of the output reference point of LMH6503 is the function of the frequency of the frequency, avmax 10V/v.Including all noise influencing factors. However, when the two inputs are connected at 50 the input noise contribution is the least. When AVMAX 10V/V, the LMH6503 has a typical flat band input reference point noise density (EIN) to 6.6nv/for 3dB BW to expand to a flat frequency band. The input average root voltage noise can be determined by the following single pole model:

Circuit layout Note

All the decoupling electrical containers shown in Figure 6 must be placed very close to ensure properly High -frequency and low impedance bypass. This is also the case for ground plane and low -induction power circuit

The layout is required. The minimum parasitic capacitance 3, 4, 5, 6, 9, 10, and 12 will ensure the best high -frequency performance. The parasitic inductance or needle 4, 5 and 9 of the component lead should also be stored at the minimum value. The output parasitic or load capacitance CL (pin 10) reduces phase margin and may cause frequency response peak or circuit oscillation. LMH6503 completely drives 100 stable when load. Reduce loads (e.g. 1K ) there is unstable possibility of unstable in the case of high frequency of more than 400MHz, especially under the capacitance load. When the LMH6503 is connected to the light load, it is recommended to add a buffer network to the output end (for example. 100 and 39pf series between LMH6503 output). CL can also connect a small resistance string to the output end (pin 10) in the following ways. Ingredient parasites also affect high -frequency results. Therefore, it is recommended to use metal membrane resistors such as RN55D or lead -free components, such as surface installation equipment. It is not recommended to use high -specification sockets. NATIONAL SEMICONDUCTOR recommends the following assessment as a guide for high-frequency layout and auxiliary device testing and characteristic description: The number of equipment package assessment boards

LMH6503MA SOIC-14 CLC730033

LMH6503MT TSSOP-14 CLC730146 [123 123 ] Single power operation

You can use a single power supply to operate LMH6503. To do this, connect the needle 11 (GND) to the point of the potential to show two samples amp; AMP; Figure 8 between V+and V-.

The rated operating voltage of LMH6503 at a lower power supply voltage is 5V (v+-v ). Here is the display show Some operation specifications ± 2.5V (that is, frequency response, CMRR, PSRR, gain and VG, etc.). Compared with ± 5V operations, under lower power conditions: A) VG is narrowed. Reference Figure 9, note that VG_MAX (VG voltage required to get the maximum gain) is 0.5V (vs ± 2.5V), and VS ± 5V is 1.0V. ± 5V. Table 1 shows the functions of various VG voltages as V-:

(b) reduce the limit value of VG (maximum allow voltage on VG). This is due to the restrictions generated from the crystal tube inside the device. More than this limit, equipment performance will be affected (non -destructive). Figure 9, please note that in the case of V+ 2.5V and V 4V, VG_ is limited to the maximum value of VG, and the maximum gain has been reduced by 1DB. This means that these conditions have reduced the maximum allowable voltage to be lower than the level required to obtain the maximum gain. If the power supply voltage is asymmetric, refer to Figure 9 and Figure 10 to ensure that the operating area is not subject to the restraint of the VG_ limit and the excessive limit of VG -_ to the maximum curve.

(C) The maximum gain decrease. There is a maximum gain when the total power supply voltage is reduced (see the typical performance characteristic chart of the gain and VG (vs ± 2.5 volts). Show 9 Figure 10 shows similar diagrams and references of V+ 5V operations.

Application circuit

Four Elephant Restrictions

The application of multiplication, square, or other non -linear functions can be implemented with a four -elephant limited multiplication. The LMH6503 realizes the four -elephant limited multiplication instruments as shown in Figure 11:

Frequency plastic surgery [ 123]

Frequency plastic surgery and bandwidth expansion LMH6503 can be implemented by parallel networks connected by the RG port. The display diagram of the displayed network graphics 12 will effectively expand the bandwidth of LMH6503. ] Second -order adjustable band pass filter

LMH6503 variable incremental amplifier is placed in the feedback circuit, providing signal processing functions, such as the second -order adjustable band of the filter. The order band controls the voltage VG by using the gain of LMH6503. The integral device uses LMH6682 to provide the coefficient of the transmission function.