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MAX4205EUA-T中文资料

________________General Description

The MAX4200–MAX4205 are ultra-high-speed, open-loop buffers featuring high slew rate, high output cur-rent, low noise, and excellent capacitive-load-driving capability. The MAX4200/MAX4201/MAX4202 are sin-gle buffers, while the MAX4203/MAX4204/MAX4205 are dual buffers. The MAX4201/MAX4204 have integrated 50?termination resistors, making them ideal for driv-ing 50?transmission lines. The MAX4202/MAX4205include 75?back-termination resistors for driv-ing 75?transmission lines. The MAX4200/MAX4203have no internal termination resistors.

The MAX4200–MAX4205 use a proprietary architecture to achieve up to 780MHz -3dB bandwidth, 280MHz 0.1dB gain flatness, 4200V/μs slew rate, and ±90mA output current drive capability. They operate from ±5V supplies and draw only 2.2mA of quiescent current.These features, along with low-noise performance, make these buffers suitable for driving high-speed analog-to-digital converter (ADC) inputs or for data-communica-tions applications.

________________________Applications

High-Speed DAC Buffers Wireless LANs

Digital-Transmission Line Drivers High-Speed ADC Input Buffers IF/Communications Systems

____________________________Features

?2.2mA Supply Current

?High Speed

780MHz -3dB Bandwidth (MAX4201/MAX4202)280MHz 0.1dB Gain Flatness (MAX4201/MAX4202)4200V/μs Slew Rate ?Low 2.1nV/√Hz Voltage-Noise Density ?Low 0.8pA/√Hz Current-Noise Density

?High ±90mA Output Drive (MAX4200/MAX4203)?Excellent Capacitive-Load-Driving Capability ? Available in Space-Saving SOT23 or μMAX ?Packages

MAX4200–MAX4205

Ultra-High-Speed, Low-Noise, Low-Power,

SOT23 Open-Loop Buffers

________________________________________________________________Maxim Integrated Products 1

19-1338; Rev 3; 3/07

_______________Ordering Information

___________Typical Application Circuit

PART

NO. OF BUFFERS INTERNAL

OUTPUT TERMINATION

(?)

PIN-PACKAGE

MAX42042508 SO/μMAX MAX42001—8 SO, 5 SOT23MAX42011508 SO, 5 SOT23MAX4205

8 SO/μMAX

MAX42021758 SO, 5 SOT23MAX42032—8 SO/μMAX ___________________________Selector Guide

Pin Configurations appear at end of data sheet.

For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at https://www.wendangku.net/doc/0417341721.html,.

μMAX is a registered trademark of Maxim Integrated Products, Inc.

temperature range.

M A X 4200–M A X 4205

Ultra-High-Speed, Low-Noise, Low-Power,SOT23 Open-Loop Buffers 2_______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

DC ELECTRICAL CHARACTERISTICS

(V CC = +5V, V EE = -5V, R L = ∞, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

Supply Voltage (V CC to V EE )................................................+12V Voltage on Any Pin to GND..............(V EE - 0.3V) to (V CC + 0.3V)Output Short-Circuit Duration to GND........................Continuous Continuous Power Dissipation (T A = +70°C)

5-Pin SOT23 (derate 7.1mW/°C above +70°C).............571mW 8-Pin μMAX (derate 4.1mW/°C above +70°C)..............330mW 8-Pin SO (derate 5.9mW/°C above +70°C)...................471mW

Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range.............................-65°C to +150°C Lead Temperature (soldering, 10s).................................+300°C

MAX4200–MAX4205

Ultra-High-Speed, Low-Noise, Low-Power,

SOT23 Open-Loop Buffers

_______________________________________________________________________________________3

AC ELECTRICAL CHARACTERISTICS

(V CC = +5V, V EE = -5V, R L = 100?for MAX4200/MAX4201/MAX4203/MAX4204, R L = 150?for MAX4202/MAX4205, T A = T MIN to T MAX , unless otherwise noted. Typical values are at T A = +25°C.)

Note 1:Tested with no load; increasing load will decrease input impedance.

M A X 4200–M A X 4205

Ultra-High-Speed, Low-Noise, Low-Power,SOT23 Open-Loop Buffers 4_______________________________________________________________________________________

__________________________________________Typical Operating Characteristics

(V CC = +5V, V EE = -5V, R L = 100?for MAX4200/MAX4201/MAX4203/MAX4204, R L = 150?for MAX4202/MAX4205, unless otherwise noted.)

4-6100k

10M 100M

1G MAX4200

SMALL-SIGNAL GAIN vs. FREQUENCY

-4-5-3

FREQUENCY (Hz)

N O R M A L I Z E D G A I N (d B )

-2-102134-6

100k 1M 10M 100M 1G MAX4201/MAX4202

SMALL-SIGNAL GAIN vs. FREQUENCY

-4-5-3

FREQUENCY (Hz)

N O R M A L I Z E D G A I N (d B )

-2-102134

-6

100k 1M 10M 100M 1G

MAX4200/MAX4201/MAX4202LARGE-SIGNAL GAIN vs. FREQUENCY

-4-5

-3FREQUENCY (Hz)

N O R M A L I Z E D G A I N (d B )

-2-102134-6100k

10M 100M

MAX4203

SMALL-SIGNAL GAIN vs. FREQUENCY

-4-5

-3FREQUENCY (Hz)

N O R M A L I Z E D G A I N (d B )

-2-102135-5100k

10M

100M

10G GROUP DELAY vs. FREQUENCY

-3-4-2M A X 4200/25-07

FREQUENCY (Hz)G R O U P D E L A Y (n s )

-1013244-6100k

10M

100M

10G

MAX4204/MAX4205

SMALL-SIGNAL GAIN vs. FREQUENCY

-4-5

-3

FREQUENCY (Hz)

N O R M A L I Z E D G A I N (d B )

-2-102134

-6

100k 1M 10M 100M 1G

MAX4203/MAX4204/MAX4205LARGE-SIGNAL GAIN vs. FREQUENCY

-4-5-3

FREQUENCY (Hz)

N O R M A L I Z E D G A I N (d B )

-2-102130-100

100k 1M 10M 100M 1G 10G POWER-SUPPLY REJECTION

vs. FREQUENCY

-80-90-70M A X 4200/25-08

FREQUENCY (Hz)

P S R (d B )

-60-50-40-20-30-109000

0 1.0 3.02.5 5.0

SLEW RATE vs. OUTPUT VOLTAGE

300020001000400070008000M A X 4200/4205-09

OUTPUT VOLTAGE (Vp-p)

S L E W R A T E (V /μs ) 1.5 2.00.5 3.550006000 4.0 4.5

MAX4200–MAX4205

Ultra-High-Speed, Low-Noise, Low-Power,

SOT23 Open-Loop Buffers

_______________________________________________________________________________________5

0-10-100

100k 100M

10M 1M MAX4200/MAX4201/MAX4202HARMONIC DISTORTION vs. FREQUENCY

-60-70-80-90-30-40-50-20

FREQUENCY (Hz)

H A R M O N I C D I S T O R T I O N (d B c )

0-10-100

100k

100M

10M

MAX4203/MAX4204/MAX4205HARMONIC DISTORTION vs. FREQUENCY

-60-70-80-90-30-40-50-20

FREQUENCY (Hz)

H A R M O N I C D I S T O R T I O N (d B c )

100

100k

10M 100M

MAX4200/MAX4203

OUTPUT IMPEDANCE vs. FREQUENCY

M A X 4200/4205-12

FREQUENCY (Hz)

O U T P U T I M P E D A N C E (?)

100

10100k

10M 100M

MAX4201/MAX4204

OUTPUT IMPEDANCE vs. FREQUENCY

M A X 4200/4205-13

FREQUENCY (Hz)

O U T P U T I M P E D A N C E (?)

1001

100

10k

100k

10M

INPUT VOLTAGE-NOISE DENSITY

vs. FREQUENCY

M A X 4200/4205-16

FREQUENCY (Hz)

V O L T A G E N O I S E D E N S I T Y (n V /H z )

10100

10100k

10M 100M

MAX4202/MAX4205

OUTPUT IMPEDANCE vs. FREQUENCY

M A X 4200/4205-14

FREQUENCY (Hz)

O U T P U T I M P E D A N C E (?)

-100

100k

10M

100M

10G

MAX4203/MAX4204/MAX4205CROSSTALK vs. FREQUENCY

-80-90

M A X 4200/4205-15

FREQUENCY (Hz)

C R O S S T A L K (d B )

-60-70-40-50-20-30-10100.1

100

10k

100k

10M

INPUT CURRENT-NOISE DENSITY

vs. FREQUENCY

M A X 4200/4205-17

FREQUENCY (Hz)

C U R R E N T N O I S E

E N S I T Y (p A /√H z )

1.0

-0.05

1000

100

DIFFERENTIAL GAIN AND PHASE

(R L = 150?)

-0.5

000.050.50.101.00.200.151.5

IRE

D I F F P H A S

E (d e g )

D I F F G A I N (%)

M A X 4200/4205-18

_________________________________Typical Operating Characteristics (continued)

(V CC = +5V, V EE = -5V, R L = 100?for MAX4200/MAX4201/MAX4203/MAX4204, R L = 150?for MAX4202/MAX4205, unless otherwise noted.)

M A X 4200–M A X 4205

Ultra-High-Speed, Low-Noise, Low-Power,SOT23 Open-Loop Buffers 6_______________________________________________________________________________________

_________________________________Typical Operating Characteristics (continued)

(V CC = +5V, V EE = -5V, R L = 100?for MAX4200/MAX4201/MAX4203/MAX4204, R L = 150?for MAX4202/MAX4205, unless otherwise noted.)

04286121014-5

-3

-2

-4

-1

5GAIN ERROR vs. INPUT VOLTAGE

INPUT VOLTAGE (V)

G A I N E R R O R (%)

3265498710

015020050100250300350400OUTPUT VOLTAGE SWING vs. EXTERNAL LOAD RESISTANCE

EXTERNAL LOAD RESISTANCE (

O U T P U T V O L T A

G E S W I N G (V p -p

)

IN VOLTAGE 50mV/div

OUT

GND

TIME (5ns/div)

SMALL-SIGNAL PULSE RESPONSE

MAX4200-21

IN VOLTAGE 50mV/div

OUT

GND

TIME (5ns/div)

MAX4200/MAX4203

SMALL-SIGNAL PULSE RESPONSE

IN VOLTAGE 50mV/div

OUT

GND GND

TIME (5ns/div)

MAX4201/MAX4202/MAX4204/MAX4205

SMALL-SIGNAL PULSE RESPONSE

C LOA

D = 22pF

IN VOLTAGE 1V/div

OUT

GND

TIME (5ns/div)

LARGE-SIGNAL PULSE RESPONSE

MAX4200-24

MAX4200–MAX4205

Ultra-High-Speed, Low-Noise, Low-Power,

SOT23 Open-Loop Buffers

_______________________________________________________________________________________7

-5-2-3-4-1012345-40

-15

INPUT OFFSET VOLTAGE vs. TEMPERATURE

M A X 4200-28

TEMPERATURE (°C)

I N P U T O F F S E T V O L T A G E (m V )

-5

-2-3-4-1012345-40

-15

INPUT BIAS CURRENT vs. TEMPERATURE

M A X 4200-29

TEMPERATURE (°C)

I N P U T B I A S C U R R E N T (μA )

3.03.2

3.6

3.4

3.8

4.0

-40

-15

MAX4200/MAX4203OUTPUT VOLTAGE SWING vs. TEMPERATURE

TEMPERATURE (°C)

V O L T A G E S W I N G (V p -p

)

_________________________________Typical Operating Characteristics (continued)

(V CC = +5V, V EE = -5V, R L = 100?for MAX4200/MAX4201/MAX4203/MAX4204, R L = 150?for MAX4202/MAX4205, unless otherwise noted.)

IN VOLTAGE 1V/div

OUT

GND GND

TIME (5ns/div)

MAX4200/MAX4203

LARGE-SIGNAL PULSE RESPONSE

C LOA

D = 15pF

VOLTAGE 1V/div

OUT

GND

TIME (5ns/div)

MAX4201/MAX4202/MAX4204/MAX4205

LARGE-SIGNAL PULSE RESPONSE

1.02.01.5

3.02.53.5

4.0

-40

-15

SUPPLY CURRENT (PER BUFFER)

vs. TEMPERATURE

M A X 4200-27

TEMPERATURE (°C)

S U P P L Y C U R R E N T (m A )

_______________Detailed Description

The MAX4200–MAX4205 wide-band, open-loop buffers feature high slew rates, high output current, low 2.1nV √Hz voltage-noise density, and excellent capaci-tive-load-driving capability. The MAX4200/MAX4203are single/dual buffers with up to 660MHz bandwidth,230MHz 0.1dB gain flatness, and a 4200V/μs slew rate.The MAX4201/MAX4204 single/dual buffers with inte-grated 50?output termination resistors, up to 780MHz bandwidth, 280MHz gain flatness, and a 4200V/μs slew rate, are ideally suited for driving high-speed signals over 50?cables. The MAX4202/MAX4205 provide bandwidths up to 720MHz, 230MHz gain flatness,4200V/μs slew rate, and integrated 75?output termina-tion resistors for driving 75?cables.

With an open-loop gain that is slightly less than +1V/V,these devices do not have to be compensated with the internal dominant pole (and its associated phase shift)that is present in voltage-feedback devices. This fea-ture allows the MAX4200–MAX4205 to achieve a nearly constant group delay time of 405ps over their full fre-quency range, making them well suited for a variety of RF and IF signal-processing applications.

These buffers operate with ±5V supplies and consume only 2.2mA of quiescent supply current per buffer while providing up to ±90mA of output current drive capability.

__________Applications Information

Power Supplies

The MAX4200–MAX4205 operate with dual supplies from ±4V to ±5.5V. Both V CC and V EE should be bypassed to the ground plane with a 0.1μF capacitor located as close to the device pin as possible.

Layout Techniques

Maxim recommends using microstrip and stripline tech-niques to obtain full bandwidth. To ensure that the PC board does not degrade the amplifier’s performance,design it for a frequency greater than 6GHz. Pay care-ful attention to inputs and outputs to avoid large para-sitic capacitance. Whether or not you use a constant-impedance board, observe the following guidelines when designing the board:

?Do not use wire-wrap boards, because they are too inductive.?Do not use IC sockets, because they increase para-sitic capacitance and inductance.

M A X 4200–M A X 4205

Ultra-High-Speed, Low-Noise, Low-Power,SOT23 Open-Loop Buffers 8_______________________________________________________________________________________

______________________________________________________________Pin Description

MAX4200–MAX4205

Ultra-High-Speed, Low-Noise, Low-Power,

SOT23 Open-Loop Buffers

_______________________________________________________________________________________9

?Use surface-mount instead of through-hole compo-nents for better high-frequency performance.?Use a PC board with at least two layers; it should be as free from voids as possible.

?Keep signal lines as short and as straight as possi-ble. Do not make 90°turns; round all corners.

Input Impedance

The MAX4200–MAX4205 input impedance looks like a 500k ?resistor in parallel with a 2pF capacitor. Since these devices operate without negative feedback, there is no loop gain to transform the input impedance upward, as in closed-loop buffers. As a consequence,the input impedance is directly related to the output impedance. I f the output load impedance decreases,the input impedance also decreases. I nductive input sources (such as an unterminated cable) may react with the input capacitance and produce some peaking in the buffer’s frequency response. This effect can usu-ally be minimized by using a properly terminated trans-mission line at the buffer input, as shown in Figure 1.

Output Current and Gain Sensitivity

The absence of negative feedback means that open-loop buffers have no loop gain to reduce their effective output impedance. As a result, open-loop devices usu-ally suffer from decreasing gain as the output current is decreased. The MAX4200–MAX4205 include local feedback around the buffer’s class-AB output stage to ensure low output impedance and reduce gain sensitiv-ity to load variations. This feedback also produces demand-driven current bias to the output transistors for ±90mA (MAX4200/MAX4203) drive capability that is rel-atively independent of the output voltage (see Typical Operating Characteristics ).

Output Capacitive Loading and Stability

The MAX4200–MAX4205 provide maximum AC perfor-mance with no load capacitance. This is the case when the load is a properly terminated transmission line.However, these devices are designed to drive any load capacitance without oscillating, but with reduced AC per-formance.

Since the MAX4200–MAX4205 operate in an open-loop configuration, there is no negative feedback to be transformed into positive feedback through phase shift introduced by a capacitive load. Therefore, these devices will not oscillate with capacitive loading, unlike similar buffers operating in a closed-loop configuration.However, a capacitive load reacting with the buffer’s output impedance can still affect circuit performance. A capacitive load will form a lowpass filter with the buffer’s output resistance, thereby limiting system

bandwidth. With higher capacitive loads, bandwidth is dominated by the RC network formed by R T and C L ;the bandwidth of the buffer itself is much higher. Also note that the isolation resistor forms a divider that decreases the voltage delivered to the load.

Another concern when driving capacitive loads results from the amplifier’s output impedance, which looks inductive at high frequency. This inductance forms an L-C resonant circuit with the capacitive load and caus-es peaking in the buffer’s frequency response.

Figure 2 shows the frequency response of the MAX4200/MAX4203 under different capacitive loads. To settle out some of the peaking, the output requires an iso-lation resistor like the one shown in Figure 3. Figure 4 is a plot of the MAX4200/MAX4203 frequency response with capacitive loading and a 10?isolation resistor. In many applications, the output termination resistors included in the MAX4201/MAX4202/ MAX4204/MAX4205 will serve this purpose, reducing component count and board space. Figure 5 shows the MAX4201/MAX4202/MAX4204/MAX4205 frequency response with capacitive loads of 47pF, 68pF, and 120pF.

Coaxial Cable Drivers

Coaxial cable and other transmission lines are easily dri-ven when properly terminated at both ends with their characteristic impedance. Driving back-terminated transmission lines essentially eliminates the line’s capaci-tance. The MAX4201/MAX4204, with their integrated 50?output termination resistors, are ideal for driving 50?cables. The MAX4202/MAX4205 include integrated 75?termination resistors for driving 75?cables. Note that the output termination resistor forms a voltage divider with the load resistance, thereby decreasing the amplitude of the signal at the receiving end of the cable by one half (see the Typical Application Circuit).

Figure 1. Using a Properly Terminated Input Source

M A X 4200–M A X 4205

Ultra-High-Speed, Low-Noise, Low-Power,SOT23 Open-Loop Buffers 10______________________________________________________________________________________

Figure 2. MAX4200/MAX4203 Small-Signal Gain vs.

Frequency with Load Capacitance and No Isolation Resistor

Figure 3. Driving a Capacitive Load Through an Isolation Resistor

Figure 4. MAX4200/MAX4203 Small-Signal Gain vs.

Frequency with Load Capacitance and 10?Isolation Resistor

Figure 5. MAX4201/MAX4202/MAX4204/MAX4205 Small-Signal Gain vs. Frequency with Capacitive Load and No External Isolation Resistor

MAX4200–MAX4205

Ultra-High-Speed, Low-Noise, Low-Power,

SOT23 Open-Loop Buffers

______________________________________________________________________________________11

__________________________________________________________Pin Configurations

___________________Chip Information

TRANSISTOR COUNTS:

MAX4200/MAX4201/MAX4202: 33MAX4203/MAX4204/MAX4205: 67SUBSTRATE CONNECTED TO V EE

M A X 4200–M A X 4205

Ultra-High-Speed, Low-Noise, Low-Power,SOT23 Open-Loop Buffers 12______________________________________________________________________________________

Package Information

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to https://www.wendangku.net/doc/0417341721.html,/packages .)

MAX4200–MAX4205

Ultra-High-Speed, Low-Noise, Low-Power,

SOT23 Open-Loop Buffers

______________________________________________________________________________________13

Package Information (continued)

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to https://www.wendangku.net/doc/0417341721.html,/packages .)

S O T -23 5L .E P

M A X 4200–M A X 4205

Ultra-High-Speed, Low-Noise, Low-Power,SOT23 Open-Loop Buffers Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

14____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600?2007 Maxim Integrated Products

is a registered trademark of Maxim Integrated Products, Inc.

Package Information (continued)

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to https://www.wendangku.net/doc/0417341721.html,/packages .)

Revision History

Pages changed at Rev 3: 1–5, 8, 10–14