Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Custom amplification Variable V factor WQFN 32

26 dB

OUTA+

OUTA-

+5V

INA+

INA-

26 dB

INB+

INB-

OUTB+

OUTB-

Attenuator

0 dB to 31.5 dB

Attenuator

0 dB to 31.5 dB

ATTEN_A

LATCH _A

EN_A

SPI

ATTEN_B

LATCH _B

EN_B

Digital

Control

PULSE_A

PULSE_B

GND

0 4 8 12 16 20 24 28 32

-0.20

-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

0.20

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

GAIN MATCHING ERROR (dB)

ATTENUATION (dB)

PHASE MATCHING ERROR (degrees)

Gain Matching Error

Phase Matching Error

LMH6521

www.ti.com

SNOSB47D –MAY 2011–REVISED MARCH 2013

High Performance Dual DVGA

Check for Samples: LMH6521

FEATURES

DESCRIPTION

The LMH6521 contains two high performance,

• OIP3 of 48.5 dBm at 200 MHz

digitally controlled variable gain amplifiers (DVGA).

• Maximum Voltage Gain of 26 dB

Both channels of the LMH6521 have an independent,

• Gain Range of 31.5 dB with 0.5dB Step Size

digitally controlled attenuator followed by a high

• Channel Gain Matching of ±0.04 dB

linearity, differential output amplifier. Each block has

• Noise Figure of 7.3 dB at Maximum Gain

been optimized for low distortion and maximum

system design flexibility. Each channel has a high

• -3 dB Bandwidth of 1200 MHz

speed power down mode.

• Low Power Dissipation

The internal digitally controlled attenuator provides

• Independent Channel Power Down

precise 0.5dB gain steps over a 31.5dB range. Serial

• Three Gain Control Modes:

and parallel programming options are provided. Serial

– Parallel Interface

mode programming utilizes the SPI interface. A Pulse

mode is also offered where simple up or down

– Serial Interface (SPI)

commands can change the gain one step at a time.

– Pulse Mode Interface

The output amplifier has a differential output allowing

• Temperature Range –40°C to +85°C

10V

PPD

signal swings on a single 5V supply. The low

• Thermally Enhanced, 32–Pin WQFN Package

impedance output provides maximum flexibility when

driving filters or analog to digital converters.

APPLICATIONS

• Cellular Base Stations

• Wideband and Narrowband IF Sampling

Receivers

• Wideband Direct Conversion

• Digital Pre-Distortion

• ADC Driver

Figure 1. LMH6521 Block Diagram Figure 2. Channel Matching Error (Ch A – Ch B)

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.

2All trademarks are the property of their respective owners.

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.

Summary of content (29 pages)

PAGE 1
LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 High Performance Dual DVGA Check for Samples: LMH6521 FEATURES DESCRIPTION • • • • • • • • • The LMH6521 contains two high performance, digitally controlled variable gain amplifiers (DVGA). 1 • • OIP3 of 48.5 dBm at 200 MHz Maximum Voltage Gain of 26 dB Gain Range of 31.5 dB with 0.5dB Step Size Channel Gain Matching of ±0.04 dB Noise Figure of 7.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 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 ESD Tolerance (1) (2) (3) Human Body Model 2 kV Machine Model 200V Charged Device Model 750V −0.6V to 5.5V Positive Supply Voltage (Pin 14, 27) Differential Voltage between Any Two Grounds <200 mV −0.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 5V Electrical Characteristics (1) The following specifications apply for single supply with V+ = 5V, Differential VOUT = 4VPP, RL= 200Ω, TA=25°C, fin = 200 MHz, and Maximum Gain (0 attenuation). Boldface limits apply at temperature extremes.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com 5V Electrical Characteristics (1) (continued) The following specifications apply for single supply with V+ = 5V, Differential VOUT = 4VPP, RL= 200Ω, TA=25°C, fin = 200 MHz, and Maximum Gain (0 attenuation). Boldface limits apply at temperature extremes. Symbol Parameter Conditions Min (2) Typ (3) Max (2) Units Power Requirements VCC Supply Voltage 5.0 5.25 V ICC Supply Current Both Channels Enabled 4.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 PIN DESCRIPTIONS Pin Number Symbol Description 30, 11 INA+, INB+ Amplifier non—inverting input. Internally biased to mid supply. Input voltage should not exceed V+ or go below GND by more than 0.5V. 29, 12 INA−, INB− Amplifier inverting input. Internally biased to mid supply. Input voltage should not exceed V+ or go below GND by more than 0.5V. 24, 17 OUTA+, OUTB+ Amplifier non—inverting output. Externally biased to 0V.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 Typical Performance Characteristics V+ = 5V, Differential VOUT = 4VPP, RL = 200Ω, TA=25 °C, fin = 200 MHz, and Maximum Gain (0 Attenuation) Gain Flatness vs. Temperature Frequency Response 2dB Gain Steps 27.0 30 26.8 25 26.6 20 GAIN (dB) 26.4 GAIN (dB) 15 10 5 26.2 26.0 25.8 25.6 0 25.4 -5 25.2 100 MHz 200 MHz 300 MHz 400 MHz 25.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com Typical Performance Characteristics (continued) V+ = 5V, Differential VOUT = 4VPP, RL = 200Ω, TA=25 °C, fin = 200 MHz, and Maximum Gain (0 Attenuation) Third Order Harmonic Distortion vs. Frequency Second Order Harmonic Distortion vs.
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LMH6521 www.ti.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com Typical Performance Characteristics (continued) V+ = 5V, Differential VOUT = 4VPP, RL = 200Ω, TA=25 °C, fin = 200 MHz, and Maximum Gain (0 Attenuation) Supply Current vs. Temperature Channel To Channel Isolation -30 250 -40 ISOLATION (dB) SUPPLY CURRENT (mA) Both Channels Enabled 240 230 220 210 Vs = 4.5V Vs = 5.0V Vs = 5.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 APPLICATION INFORMATION VCC 1 PH 0.01 PF RF 40.2: 200: 0.01 PF ½ LMH6521 ADC 40.2: 0.01 PF 0.01 PF 1 PH LO 6 GAIN 0-5 LATCH ENABLE Figure 26. LMH6521 Typical Application INTRODUCTION The LMH6521 is a dual, digitally controlled variable gain amplifier designed for narrowband and wideband intermediate frequency sampling applications. The LMH6521 is optimized for accurate 0.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com +5V 0.01 PF 50: 0.01 PF + 40.2: OUT+ IN+ 0.01 PF ½ LMH6521 AC 100: OUT- 0.01 PF IN- 50: 40.2: 1 PH 6 0.01 PF 1 PH A0 - A5 Figure 27. Basic Operating Connection +5V Attenuator INA+ OUTA+ 26 dB INA- ATTEN_A LATCH _A OUTA- 0 dB to 31.5 dB 6 EN_A PULSE_A SPI ATTEN_B LATCH _B 2 4 6 Digital Control EN_B PULSE_B INB+ 2 Attenuator OUTB+ 26 dB INB- OUTB- 0 dB to 31.5 dB GND Figure 28.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 INPUT CHARACTERISTICS The LMH6521 input impedance is set by internal resistors to a nominal 200Ω. At higher frequencies device parasitic reactances will start to impact the input impedances. Refer to Figure 24 in Typical Performance Characteristics for more details For many AC coupled applications the impedance can be easily changed using LC circuits to transform the actual impedance to the desired impedance.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com 1P RT + FILTER 0.01P +IN RT LMH6521 RT . 1P RT VRM ADC16DV160 -IN 0.01P Figure 30. Example Output Configuration The outputs of the LMH6521 need to be biased to near ground potential. On the evaluation board, 1µH inductors are installed to provide proper output biasing.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 PARALLEL MODE (MOD1= 1, MOD0 = 1) When designing a system that requires very fast gain changes parallel mode is the best selection. Refer to for pin definitions of the LMH6521 in parallel mode. The LMH6521 has a 6-bit gain control bus as well as latch pins LATA and LATB for channels A and B. When the latch pin is low, data from the gain control pins is immediately sent to the gain circuit (i.e. gain is changed immediately).
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com ENA and ENB pins are active in serial mode. For fast disable capability these pins can be used and the serial register will hold the last active gain state. These pins will float high and can be left disconnected for serial mode. The serial control bus can also disable the DVGA channels, but at a much slower speed. The serial enable function is an AND function.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 D2 D1 D0 (LSB) D2 D1 17 SCLK SCSb COMMAND FIELD SDI C7 C6 C5 C4 R/Wb 0 0 0 DATA FIELD C3 C2 C1 C0 A3 A2 A1 A0 Reserved (3-bits) D7 D6 (MSB) D5 D4 D3 Write DATA Address (4-bits) D7 D6 (MSB) D5 D4 D3 D0 (LSB) Hi-Z Read DATA SDO Data (8-bits) Single Access Cycle Figure 35. Serial Interface Protocol (SPI compatible) R/Wb Read / Write bit.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com Control Logic LMH6521 CLK CSb SDI Clock out Chip Select out Data Out Data In SDO R 20: V+ (Logic High) For SDO (MISO) pin only: VOH = V+, VOL = (V+) ± [0.012*(R+20) + Vcesat] 12 mA Max Recommended: R = 300 Ohms to 2000 Ohms V+ (Logic) = 2.5V to 3.3V Figure 36. Serial Mode 4–wire Connection st 1 clock th th 8 clock 16 clock SCLK tCSH tCSS tCSH tCSS CSb tOZD SDO tODZ tOD D7 D1 D0 Figure 37. Read Timing Table 3.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 tPL tPH 16th clock SCLK tSU SDI tH Valid Data Valid Data Figure 38. Write Timing, Data Written to SDI Pin Table 4. Write Timing Data Input on SDI Pin Parameter Description tPL Minimum clock low time (clock duty dycle) tPH Minimum clock high time (clock duty cycle) tSU Input data setup time tH Input data hold time PULSE MODE (MOD1= 0, MOD0 = 1) Pulse mode is a simple yet fast way to adjust gain settings.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com RESET TIMING UP tRW DN Figure 39. Pulse Mode Timing THERMAL MANAGEMENT The LMH6521 is packaged in a thermally enhanced WQFN package and features an exposed pad that is connected to the GND pins. It is recommended that the exposed pad be attached directly to a large power supply ground plane for maximum heat dissipation.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 2.5 2.0 OUT + 2.5 VPP 1.5 VOUT (V) 1.0 0.5 0.0 1.25 VP COMMON MODE = 0V -0.5 -1.0 -1.5 -2.0 -2.5 0 5 VPPD (DIFFERENTIAL) OUT - 45 90 135 180 225 270 315 360 PHASE (°) Figure 40. Output Voltage with Respect to Output Common Mode R1 C1 L1 AMP VOUT - L5 R4 C2 L2 AMP VOUT + ADC ZIN C3 AMP ZOUT R3 ADC VIN + ADC VIN - R2 ADC VCM Figure 41.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com Table 6. LMH6521+BPF+ADC16DV160 vs Typical ADC16DV160 Specifications ADC Input SNR (dBFS) SFDR (dBFS) LMH6521+BPF+ADC16DV160 –1dBFS 75.5 82 ADC16DV160 only –1dBFS 76 89 Configuraton POWER SUPPLIES The LMH6521 was designed primarily to be operated on 5V power supplies. The voltage range for VCC is 4.75V to 5.25V.
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LMH6521 www.ti.com SNOSB47D – MAY 2011 – REVISED MARCH 2013 Table 7.
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LMH6521 SNOSB47D – MAY 2011 – REVISED MARCH 2013 www.ti.com REVISION HISTORY Changes from Revision C (March 2013) to Revision D • 24 Page Changed layout of National Data Sheet to TI format ..........................................................................................................
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE MATERIALS INFORMATION www.ti.com 26-Mar-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing LMH6521SQ/NOPB WQFN RTV 32 LMH6521SQE/NOPB WQFN RTV LMH6521SQX/NOPB WQFN RTV SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant 1000 178.0 12.4 5.3 5.3 1.3 8.0 12.0 Q1 32 250 178.0 12.4 5.3 5.3 1.3 8.0 12.0 Q1 32 4500 330.0 12.4 5.3 5.3 1.3 8.0 12.
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PACKAGE MATERIALS INFORMATION www.ti.com 26-Mar-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LMH6521SQ/NOPB WQFN RTV 32 1000 213.0 191.0 55.0 LMH6521SQE/NOPB WQFN RTV 32 250 213.0 191.0 55.0 LMH6521SQX/NOPB WQFN RTV 32 4500 367.0 367.0 35.
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MECHANICAL DATA RTV0032A SQA32A (Rev B) www.ti.
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