19-4754; Rev 1; 8/01 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable ____________________________Features The MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 are precision, closed-loop, gain of +2 (or -1) buffers featuring high slew rates, high output current drive, and low differential gain and phase error. They operate with a single 3.15V to 11V supply or with 1.575V to 5.5V dual supplies. The input common-mode voltage range extends 100mV beyond the negative power-supply rail, and the output swings Rail-to-Rail(R). These devices require only 5.5mA of quiescent supply current while achieving a 230MHz -3dB bandwidth and a 600V/s slew rate. In addition, the MAX4215/ MAX4219 have a disable feature that reduces the supply current to 400A per buffer. Input voltage noise is only 10nV/Hz, and input current noise is only 1.3pA/Hz. This buffer family is ideal for low-power/lowvoltage applications requiring wide bandwidth, such as video, communications, and instrumentation systems. For space-sensitive applications, the MAX4214 comes in a miniature 5-pin SOT23 package. Internal Precision Resistors for Closed-Loop Gains of +2V/V or -1V/V _______________Ordering Information High Speed 230MHz -3dB Bandwidth 90MHz 0.1dB Gain Flatness (MAX4219/MAX4222) 600V/s Slew Rate Single 3.3V/5.0V Operation Outputs Swing Rail-to-Rail Input Common-Mode Range Extends Beyond VEE Low Differential Gain/Phase Error: 0.03%/0.04 Low Distortion at 5MHz -72dBc SFDR -71dB Total Harmonic Distortion High Output Drive: 120mA Low 5.5mA Supply Current 400A Shutdown Supply Current (MAX4215/MAX4219) PINPACKAGE TOP MARK Space-Saving SOT23, MAX, or QSOP Packages MAX4214EUK-T -40C to +85C 5 SOT23-5 ABAH ______________________Selector Guide MAX4215ESA 8 SO 8 MAX 8 SO 8 MAX 14 SO 16 QSOP 14 SO 16 QSOP PART MAX4215EUA MAX4217ESA MAX4217EUA MAX4219ESD MAX4219EEE MAX4222ESD MAX4222EEE TEMP RANGE -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -40C to +85C -- -- -- -- -- -- -- -- ________________________Applications PART NO. OF AMPS MAX4214 1 No 5 SOT23 MAX4215 1 Yes 8 SO/MAX MAX4217 2 No 8 SO/MAX MAX4219 3 Yes 14 SO, 16 QSOP MAX4222 4 No 14 SO, 16 QSOP ENABLE PIN-PACKAGE __________________Pin Configurations Battery-Powered Instruments Video Line Drivers Analog-to-Digital Converter Interface CCD Imaging Systems Video Routing and Switching Systems Video Multiplexing Applications TOP VIEW OUT 1 VEE 2 Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd. VCC 4 IN- MAX4214 IN+ 3 Typical Application Circuit appears at end of data sheet. 5 SOT23-5 Pin Configurations continued at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 1 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 _________________General Description MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable ABSOLUTE MAXIMUM RATINGS Supply Voltage (VCC to VEE) ..................................................12V IN_-, IN_+, OUT_, EN_ ....................(VEE - 0.3V) to (VCC + 0.3V) Output Short-Circuit Duration to VCC or VEE ..............Continuous Continuous Power Dissipation (TA = +70C) 5-Pin SOT23 (derate 7.1mW/C above +70C).............571mW 8-Pin SO (derate 5.9mW/C above +70C)...................471mW 8-Pin MAX (derate 4.1mW/C above +70C) .............330mW 14-Pin SO (derate 8.3mW/C above +70C)................667mW 16-Pin QSOP (derate 8.3mW/C above +70C)...........667mW Operating Temperature Range ...........................-40C to +85C Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C 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. DC ELECTRICAL CHARACTERISTICS (VCC = 5V, VEE = 0, IN_- = 0, EN_ = 5V, RL = to 0, VOUT = VCC/2, noninverting configuration, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER SYMBOL Operating Supply Voltage Range VCC to VEE, guaranteed by PSRR tests Input Voltage Range VIN Input Offset Voltage VOS Input Offset Voltage Drift MIN VEE - 0.1 VCC + 0.1 RL = 50 SO, QSOP 4 10 SOT23-5, MAX 4 15 IN_+ 1 mV AV RL 50, (VEE + 0.5V) VOUT (VCC - 2.0V) 1.9 2 VCC = 5V, VEE = 0, VOUT = 2.0V 55 58 VCC = 5V, VEE = -5V, VOUT = 0 60 66 Output Current Short-Circuit Output Current IOUT ISC Output Voltage Swing VOUT RL = 150 RL = 2k Disabled Output Resistance VIL MAX4215/MAX4219 EN_ Logic High Threshold VIH MAX4215/MAX4219 2 2.1 V/V dB 25 TA = +25C 70 TA = TMIN to TMAX 60 m 120 mA 150 mA VCC - VOH 1.60 1.90 VOL - VEE 0.04 0.075 VCC - VOH 0.75 1.00 VOL - VEE 0.04 0.075 VCC - VOH 0.06 VOL - VEE 0.06 ROUT(OFF) MAX4215/MAX4219, EN_ = 0, 0 VOUT 5V EN_ Logic Low Threshold A M 45 Sinking or sourcing RL = 50 12 3 f = DC RL = 20 to VCC or VEE mV V/C 5.4 VCC = 3.3V, VEE = 0, VOUT = 0.90V V 8 Voltage Gain ROUT V IN_- IN_+, over input voltage range Output Resistance 11.0 VCC - 2.25 RIN PSRR UNITS VEE - 0.1 Input Resistance Power-Supply Rejection Ratio (Note 2) MAX IN_+ Between any two channels for MAX4217/MAX4219/MAX4222 IB TYP 3.15 TCVOS Input Offset Voltage Matching Input Bias Current CONDITIONS 1 V k VCC - 2.6 VCC - 1.6 _______________________________________________________________________________________ V V High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable (VCC = 5V, VEE = 0, IN_- = 0, EN_ = 5V, RL = to 0, VOUT = VCC/2, noninverting configuration, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER SYMBOL EN_ Logic Input Low Current IIL EN_ Logic Input High Current IIH Quiescent Supply Current (per Buffer) ICC Shutdown Supply Current ISD CONDITIONS MIN TYP MAX UNITS MAX4215/MAX4219, (VEE + 0.2V) EN_ VCC 0.5 MAX4215/MAX4219, EN_ = VEE 200 350 MAX4215/MAX4219, EN_ = VCC 0.5 10 A 5.5 7.0 mA 400 550 A MAX4215/MAX4219, disabled (EN_ = VEE) A Note 1: The MAX421_EU_ is 100% production tested at TA = 25C. Specifications over temperature limits are guaranteed by design. Note 2: PSRR for single 5V supply tested with VEE = 0, VCC = 4.5V to 5.5V; for dual 5V supply with VEE = -4.5V to -5.5V, VCC = 4.5V to 5.5V; and for single 3V supply with VEE = 0, VCC = 3.15V to 3.45V. AC ELECTRICAL CHARACTERISTICS (VCC = 5V, VEE = 0, IN_- = 0, EN_ = 5V, RL = 100 to VCC/2, noninverting configuration, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER Small-Signal -3dB Bandwidth SYMBOL BW-3dB Full-Power -3dB Bandwidth FPBW Bandwidth for 0.1dB Gain Flatness Slew Rate Settling Time to 0.1% BW0.1dB CONDITIONS MIN TYP VOUT = 100mVP-P MAX4214/MAX4215/MAX4217 230 MAX4219/MAX4222 200 VOUT = 2VP-P MAX4214/MAX4215/MAX4217 220 MAX4219/MAX4222 200 VOUT = 100mVP-P MAX4214/MAX4215/MAX4217 50 MAX4219/MAX4222 90 MAX UNITS MHz MHz MHz SR VOUT = 2V step 600 V/s tS VOUT = 2V step 45 ns 1 ns -72 dBc Rise/Fall Time tR, tF VOUT = 100mVP-P Spurious-Free Dynamic Range SFDR fC = 5MHz, VOUT = 2VP-P Second harmonic -72 Third harmonic -77 Total harmonic distortion -71 Harmonic Distortion HD VOUT = 2VP-P, fC = 5MHz Third-Order Intercept IP3 f = 10MHz 35 dBm f = 10MHz 11 dBm Input 1dB Compression Point dBc Differential Phase Error DP NTSC, RL = 150 0.04 degrees Differential Gain Error DG NTSC, RL = 150 0.03 % Input Noise-Voltage Density en f = 10kHz 10 nV/Hz Input Noise-Current Density in f = 10kHz 1.3 pA/Hz Input Capacitance CIN 1 pF 2 pF Disabled Output Capacitance COUT(OFF) MAX4215/MAX4219, EN_ = 0 _______________________________________________________________________________________ 3 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 DC ELECTRICAL CHARACTERISTICS (continued) AC ELECTRICAL CHARACTERISTICS (continued) (VCC = 5V, VEE = 0, IN_- = 0, EN_ = 5V, RL = 100 to VCC/2, noninverting configuration, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL Output Impedance ZOUT Buffer Enable Time Buffer Disable Time CONDITIONS All-Hostile Crosstalk MIN TYP MAX UNITS f = 10MHz 200 m tON MAX4215/MAX4219 100 ns tOFF MAX4215/MAX4219 Buffer Gain Matching XTALK 1 s MAX4217/MAX4219/MAX4222, f = 10MHz, VOUT = 100mVP-P 0.1 dB MAX4217/MAX4219/MAX4222, f = 10MHz, VOUT = 2VP-P -95 dB __________________________________________Typical Operating Characteristics (VCC = 5V, VEE = 0, AVCL = 2V/V, RL = 100 to VCC/2, TA = +25C, unless otherwise noted.) VOUT = 100mVP-P 8 6.4 6.3 10 9 7 6.1 6 4 GAIN (dB) 6.2 5 6.0 5 5.9 4 3 5.8 3 2 5.7 2 1 5.6 1 100k 1M 10M 100M 100k 1M 10M 100M 100k 1G 1M 10M 100M 1G FREQUENCY (Hz) FREQUENCY (Hz) FREQUENCY (Hz) MAX4219/MAX4222 SMALL-SIGNAL GAIN vs. FREQUENCY MAX4219/MAX4222 GAIN FLATNESS vs. FREQUENCY MAX4219/MAX4222 LARGE-SIGNAL GAIN vs. FREQUENCY 8 6.4 VOUT = 100mVP-P 10 6.3 9 6.1 6 4 GAIN (dB) 7 6 GAIN (dB) 6.2 6.0 5.9 5 4 3 5.8 3 2 5.7 2 1 5.6 1 0 5.5 100k 1M 10M FREQUENCY (Hz) 100M 1G 100k 1M 10M FREQUENCY (Hz) 100M 1G VOUT = 2VP-P RL = 100 8 7 5 MAX4214 toc06 VOUT = 100mVP-P MAX4214 toc05 6.5 MAX4214 toc04 10 9 0 5.5 1G VOUT = 2VP-P 8 6 0 4 VOUT = 100mVP-P 7 GAIN (dB) GAIN (dB) 6.5 MAX4214 toc02 9 MAX4214 toc01 10 MAX4214/MAX4215/MAX4217 LARGE-SIGNAL GAIN vs. FREQUENCY MAX4214/MAX4215/MAX4217 GAIN FLATNESS vs. FREQUENCY MAX4214 toc03 MAX4214/MAX4215/MAX4217 SMALL-SIGNAL GAIN vs. FREQUENCY GAIN (dB) MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable 0 100k 1M 10M FREQUENCY (Hz) _______________________________________________________________________________________ 100M 1G High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable -30 -40 -50 -60 2ND HARMONIC -80 3RD HARMONIC -90 -20 -30 -40 -50 -60 2ND HARMONIC -70 -80 0 -10 3RD HARMONIC -90 -100 1M 10M 100M f = 5MHz -20 -30 -40 -50 -60 2ND HARMONIC -70 -80 3RD HARMONIC -90 -100 -100 0 100 200 300 400 500 600 700 800 900 1k 0.5 1.0 1.5 2.0 2.5 3.0 FREQUENCY (Hz) RESISTIVE LOAD () VOLTAGE SWING (Vp-p) VOLTAGE-NOISE DENSITY vs. FREQUENCY CURRENT-NOISE DENSITY vs. FREQUENCY MAX4217/MAX4219/MAX4222 CROSSTALK vs. FREQUENCY 10 10 3.5 50 30 10 CROSSTALK (dB) NOISE (pA/ Hz) MAX4214 toc10 100 MAX4214 toc11 100k NOISE (nV/Hz) VOUT = 2VP-P f = 5MHz MAX4214 toc12 -70 0 -10 HARMONIC DISTORTION (dBc) -20 HARMONIC DISTORTION vs. VOLTAGE SWING MAX4214 toc08 VOUT = 2VP-P HARMONIC DISTORTION (dBc) HARMONIC DISTORTION (dBc) MAX4214 toc07 0 -10 HARMONIC DISTORTION vs. RESISTIVE LOAD MAX4214 toc09 HARMONIC DISTORTION vs. FREQUENCY -10 -30 -50 -70 -90 -110 -130 -150 1 1 10 100 1k 10k 100k 1M 1 10M 10 100 -30 -40 -50 -60 10M 100M CLOSED-LOOP OUTPUT IMPEDANCE vs. FREQUENCY 100 -10 1G 10 -20 IMPEDANCE () -20 1M MAX4215/MAX4219 OFF-ISOLATION vs. FREQUENCY MAX4214 toc14 0 -10 100k 10M FREQUENCY (Hz) 0 OFF-ISOLATION (dB) POWER-SUPPLY REJECTION (dB) 10 1M 10 MAX4214 toc13 20 10k 100k FREQUENCY (Hz) FREQUENCY (Hz) POWER-SUPPLY REJECTION vs. FREQUENCY 1k MAX4214 toc15 1 -30 -40 -50 -60 1 0.1 -70 -70 -80 -80 -90 100k 1M 10M FREQUENCY (Hz) 100M 0.01 100k 1M 10M FREQUENCY (Hz) 100M 100k 1M 10M 100M 1G FREQUENCY (Hz) _______________________________________________________________________________________ 5 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 _____________________________Typical Operating Characteristics (continued) (VCC = 5V, VEE = 0, AVCL = 2V/V, RL = 100 to VCC/2, TA = +25C, unless otherwise noted.) _____________________________Typical Operating Characteristics (continued) (VCC = 5V, VEE = 0, AVCL = 2V/V, RL = 100 to VCC/2, TA = +25C, unless otherwise noted.) CLOSED-LOOP BANDWIDTH vs. LOAD RESISTANCE -0.01 100 DIFF. PHASE (deg) 0 IRE 0.02 0.00 -0.02 VOUT = 100mVP-P RL = 150 VCM = 1.35V -0.04 -0.06 0 5.0 300 250 200 150 100 4.5 50 4.0 3.5 3.0 2.5 2.0 1.5 0 100 MAX4214 toc18 350 OUTPUT SWING (Vp-p) 0.01 0.00 OUTPUT SWING vs. LOAD RESISTANCE MAX4214 toc17 RL = 150 VCM = 1.35V CLOSED-LOOP BANDWIDTH (MHz) 0.04 0.03 0.02 MAX4214 toc16 DIFF. GAIN (%) DIFFERENTIAL GAIN AND PHASE 1.0 IRE 200 300 400 LOAD RESISTANCE () SMALL-SIGNAL PULSE RESPONSE LARGE-SIGNAL PULSE RESPONSE 0 100 500 25 50 75 100 125 150 175 200 225 250 LOAD RESISTANCE () ENABLE RESPONSE TIME MAX4214 toc19 MAX4214 toc20 MAX4214 toc21 5.0V (ENABLE) IN EN_ 0 (DISABLE) 25mV/div 500mV/div IN OUT OUT 1V OUT 0 20ns/div 1s/div VCM = 0.9V, RL = 100 to GROUND SMALL-SIGNAL PULSE RESPONSE (CL = 5pF) VIN = 0.5V LARGE-SIGNAL PULSE RESPONSE (CL = 5pF) MAX4214 toc22 VOLTAGE SWING vs. TEMPERATURE MAX4214 toc23 5.0 MAX4214 toc24 20ns/div VCM = 1.25V, RL = 100 to GROUND RL = 150 to 0 IN VOLTAGE SWING (Vp-p) 4.8 500mV/div IN 25mV/div MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable OUT OUT 4.6 4.4 4.2 4.0 6 20ns/div 20ns/div VCM = 1.25V, RL = 100 to 0 VCM = 1.75V, RL = 100 to 0 -50 -25 0 25 50 TEMPERATURE (C) _______________________________________________________________________________________ 75 100 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable INPUT BIAS CURRENT (A) 3 2 1 0 INPUT OFFSET CURRENT vs. TEMPERATURE 5.5 5.0 4.5 0.20 0.16 0.12 0.08 0.04 0 4.0 0 25 50 TEMPERATURE (C) 75 100 -50 -25 0 25 50 TEMPERATURE (C) 75 POWER-SUPPLY CURRENT (PER AMPLIFIER) vs. POWER-SUPPLY VOLTAGE 8 6 4 2 0 -50 -25 0 25 50 TEMPERATURE (C) 75 100 POWER-SUPPLY CURRENT (PER AMPLIFIER) vs. TEMPERATURE 7 POWER-SUPPLY CURRENT (mA) 10 100 MAX4214 toc29 -25 MAX4214 toc28 -50 MAX4214 toc27 MAX4214 toc26 6.0 MAX4214 toc25 4 POWER-SUPPLY CURRENT (mA) INPUT OFFSET VOLTAGE (mV) 5 INPUT BIAS CURRENT vs. TEMPERATURE INPUT OFFSET CURRENT (A) INPUT OFFSET VOLTAGE vs. TEMPERATURE 6 5 4 3 3 4 5 6 7 8 9 10 POWER-SUPPLY VOLTAGE (V) 11 -50 -25 0 25 50 TEMPERATURE (C) 75 100 _______________________________________________________________________________________ 7 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 _____________________________Typical Operating Characteristics (continued) (VCC = 5V, VEE = 0, AVCL = 2V/V, RL = 100 to VCC/2, TA = +25C, unless otherwise noted.) MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable _______________________________________________________________Pin Description PIN 8 NAME FUNCTION 8, 9 N.C. No Connection. Not internally connected. Tie to ground or leave open. -- -- OUT Amplifier Output 13 11 13 VEE Negative Power Supply or Ground (in single-supply operation) -- -- -- -- IN+ Noninverting Input -- -- -- -- IN- Inverting Input MAX4214 MAX4215 MAX4217 SOT23-5 SO/MAX SO/MAX SO MAX4219 QSOP SO MAX4222 QSOP -- 1, 5 -- -- 8, 9 -- 1 6 -- -- -- 2 4 4 11 3 3 -- 4 2 -- 5 7 8 4 4 4 4 VCC Positive Power Supply -- 8 -- -- -- -- -- EN Enable Amplifier -- -- -- 1 1 -- -- ENA Enable Amplifier A -- -- -- 3 3 -- -- ENB Enable Amplifier B -- -- -- 2 2 -- -- ENC Enable Amplifier C -- -- 1 7 7 1 1 OUTA Amplifier A Output -- -- 2 6 6 2 2 INA- Amplifier A Inverting Input -- -- 3 5 5 3 3 INA+ Amplifier A Noninverting Input -- -- 7 8 10 7 7 OUTB Amplifier B Output -- -- 6 9 11 6 6 INB- Amplifier B Inverting Input -- -- 5 10 12 5 5 INB+ Amplifier B Noninverting Input -- -- -- 14 16 8 10 OUTC Amplifier C Output -- -- -- 13 15 9 11 INC- Amplifier C Inverting Input -- -- -- 12 14 10 12 INC+ Amplifier C Noninverting Input -- -- -- -- -- 14 16 OUTD Amplifier D Output -- -- -- -- -- 13 15 IND- Amplifier D Inverting Input -- -- -- -- -- 12 14 IND+ Amplifier D Noninverting Input _______________________________________________________________________________________ High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable The MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 are single-supply, rail-to-rail output, voltage-feedback, closed-loop buffers that employ current-feedback techniques to achieve 600V/s slew rates and 230MHz bandwidths. These buffers use internal 500 resistors to provide a preset closed-loop gain of 2V/V in the noninverting configuration or -1V/V in the inverting configuration. Excellent harmonic distortion and differential gain/phase performance make them an ideal choice for a wide variety of video and RF signal-processing applications. Local feedback around the buffer's output stage ensures low output impedance, which reduces gain sensitivity to load variations. This feedback also produces demand-driven current bias to the output transistors for 120mA drive capability, while constraining total supply current to less than 7mA. Since the inverting input exhibits a 500 input impedance, terminate the input with a 56 resistor when configured for an inverting gain in 50 applications (terminate with 88 in 75 applications). Terminate the input with a 49.9 resistor in the noninverting case. Output terminating resistors should directly match cable impedances in either configuration. Layout Techniques Maxim recommends using microstrip and stripline techniques to obtain full bandwidth. To ensure the PC board does not degrade the buffer's performance, design it for a frequency greater than 1GHz. Pay careful attention to inputs and outputs to avoid large parasitic capacitance. Whether or not you use a constantimpedance board, observe the following guidelines when designing the board: * Don't use wire-wrapped boards. They are too inductive. ___________Applications Information * Don't use IC sockets. They increase parasitic capacitance and inductance. Power Supplies * Use surface-mount instead of through-hole components for better high-frequency performance. These devices operate from a single 3.15V to 11V power supply or from dual supplies of 1.575V to 5.5V. For single-supply operation, bypass the VCC pin to ground with a 0.1F capacitor as close to the pin as possible. If operating with dual supplies, bypass each supply with a 0.1F capacitor. * 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 possible. Do not make 90 turns; round all corners. Selecting Gain Configuration Input Voltage Range and Output Swing Each buffer in the MAX4214 family can be configured for a voltage gain of 2V/V or -1V/V. For a gain of 2V/V, ground the inverting terminal. Use the noninverting terminal as the signal input of the buffer (Figure 1a). Grounding the noninverting terminal and using the inverting terminal as the signal input configures the buffer for a gain of -1V/V (Figure 1b). The MAX4214 family's input range extends from (VEE - 100mV) to (VCC - 2.25V). Input ground sensing increases the dynamic range for single-supply applications. The outputs drive a 2k load to within 60mV of the power-supply rails. With smaller resistive loads, the output swing is reduced as shown in the Electrical Characteristics and Typical Operating Characteristics. IN+ IN IN+ OUT RTIN RTO OUT OUT RS RTO RO OUT RO 500 500 500 IN IN- 500 IN- RTIN MAX42_ _ Figure 1a. Noninverting Gain Configuration (AV = +2V/V) MAX42_ _ Figure 1b. Inverting Gain Configuration (AV = -1V/V) _______________________________________________________________________________________ 9 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 ________________Detailed Description As the load resistance decreases, the useful input range is effectively limited by the output drive capability, since the buffers have a fixed voltage gain of 2V/V or -1V/V. For example, a 50 load can typically be driven from 40mV above VEE to 1.6V below VCC, or 40mV to 3.4V when operating from a single 5V supply. If the buffer is operated in the noninverting, gain of 2V/V configuration with the inverting input grounded, the useful input voltage range becomes 20mV to 1.7V instead of the -100mV to 2.75V indicated by the Electrical Characteristics. Beyond the useful input range, the buffer output is a nonlinear function of the input, but it will not undergo phase reversal or latchup. Enable sists of five back-to-back Schottky diodes between IN_+ and IN_-. These diodes reduce the disabled output resistance from 1k to 500 when the output voltage is 3V greater or less than the voltage at IN_+. Under these conditions, the input protection diodes will be forward biased, lowering the disabled output resistance to 500. Output Capacitive Loading and Stability The MAX4214 family provides maximum AC performance with no load capacitance. This is the case when the load is a properly terminated transmission line. These devices are designed to drive up to 20pF of load capacitance without oscillating, but AC performance will be reduced under these conditions. The MAX4215/MAX4219 have an enable feature (EN_) that allows the buffer to be placed in a low-power state. When the buffers are disabled, the supply current is reduced to 400A per buffer. As the voltage at the EN_ pin approaches the negative supply rail, the EN_ input current rises. Figure 2 shows a graph of EN_ input current versus EN_ pin voltage. Figure 3 shows the addition of an optional resistor in series with the EN pin, to limit the magnitude of the current increase. Figure 4 displays the resulting EN pin input current to voltage relationship. ENABLE 10k EN_ IN+ OUT MAX42_ _ Disabled Output Resistance The MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 include internal protection circuitry that prevents damage to the precision input stage from large differential input voltages (Figure 5). This protection circuitry con- 500 0 0 -1 -20 -2 -40 -60 -80 -100 500 Figure 3. Circuit to Reduce Enable Logic-Low Input Current 20 -3 -4 -5 -6 -7 -120 -8 -140 -9 -10 -160 0 100 200 300 400 500 VIL (mV ABOVE VEE) Figure 2. Enable Logic-Low Input Current vs. Enable LogicLow Threshold 10 IN- INPUT CURRENT (A) INPUT CURRENT (A) MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable 0 100 200 300 400 500 VIL (mV ABOVE VEE) Figure 4. Enable Logic-Low Input Current vs. Enable LogicLow Threshold with 10k Series Resistor ______________________________________________________________________________________ High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable 5 MAX4214 MAX4215 MAX4217 MAX4219 MAX4222 OUT NORMALIZED GAIN (dB) IN+ CL = 15pF 4 3 CL = 10pF 2 1 0 CL = 5pF -1 -2 -3 IN500 -4 500 100k 1M 10M 100M 1G FREQUENCY (Hz) Figure 5. Input Protection Circuit Figure 6. Small-Signal Gain vs. Frequency with Load Capacitance and No Isolation Resistor 16 14 500 12 500 RISO () 10 RISO 6 VOUT MAX42_ _ VIN 8 4 CL 2 RTIN 50 0 0 50 100 150 CLOAD (pF) 200 250 Figure 7. Driving a Capacitive Load Through an Isolation Resistor Figure 8. Isolation Resistance vs. Capacitive Load Driving large capacitive loads increases the chance of oscillations occurring in most amplifier circuits. This is especially true for circuits with high loop gains, such as voltage followers. The buffer's output resistance and the load capacitor combine to add a pole and excess phase to the loop response. If the frequency of this pole is low enough to interfere with the loop response and degrade phase margin sufficiently, oscillations can occur. A second problem when driving capacitive loads results from the amplifier's output impedance, which looks inductive at high frequencies. This inductance forms an L-C resonant circuit with the capacitive load, which causes peaking in the frequency response and degrades the amplifier's gain margin. Figure 6 shows the devices' frequency response under different capacitive loads. To drive loads with greater than 20pF of capacitance or to settle out some of the peaking, the output requires an isolation resistor like the one shown in Figure 7. Figure 8 is a graph of the Optimal Isolation Resistor vs. Load Capacitance. Figure 9 shows the frequency response of the MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 when driving capacitive loads with a 27 isolation resistor. Coaxial cables and other transmission lines are easily driven when properly terminated at both ends with their characteristic impedance. Driving back-terminated transmission lines essentially eliminates the lines' capacitance. ______________________________________________________________________________________ 11 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 6 3 2 _________Typical Application Circuit RISO = 27 CL = 47pF 1 NORMALIZED GAIN (dB) MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable 0 IN+ 75 CL = 68pF -1 -2 VOUT CL = 120pF -3 75 MAX4214 -4 IN- -5 500 500 -6 -7 100k 1M 10M 100M 1G GAIN OF +2 VIDEO/RF CABLE DRIVER FREQUENCY (Hz) Figure 9. Small-Signal Gain vs. Frequency with Load Capacitance and 27 Isolation Resistor Chip Information MAX4214 TRANSISTOR COUNT: 95 MAX4215 TRANSISTOR COUNT: 95 MAX4217 TRANSISTOR COUNT: 190 MAX4219 TRANSISTOR COUNT: 299 MAX4222 TRANSISTOR COUNT: 362 SUBSTRATE CONNECTED TO VEE 12 ______________________________________________________________________________________ High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable TOP VIEW N.C. 1 IN- 2 8 EN OUTA 1 7 VCC INA- 2 MAX4215 8 VCC 7 OUTB MAX4217 IN+ 3 6 OUT INA+ 3 6 INB- VEE 4 5 N.C. VEE 4 5 INB+ SO/MAX SO/MAX ENA 1 14 OUTC ENA 1 16 OUTC ENC 2 13 INC- ENC 2 15 INC- 12 INC+ ENB 3 11 VEE VCC 4 10 INB+ INA+ 5 12 INB+ ENB 3 VCC 4 MAX4219 INA+ 5 14 INC+ MAX4219 13 VEE INA- 6 9 INB- INA- 6 11 INB- OUTA 7 8 OUTB OUTA 7 10 OUTB 9 N.C. 8 N.C. SO QSOP OUTA 1 16 OUTD 13 IND- INA- 2 15 IND- 12 IND+ INA+ 3 14 IND+ 11 VEE VCC 4 INB+ 5 10 INC+ INB+ 5 12 INC+ INB- 6 9 INC- INB- 6 11 INC- OUTB 7 8 OUTC OUTB 7 10 OUTC OUTA 1 14 OUTD INA- 2 INA+ 3 VCC 4 MAX4222 MAX4222 N.C. 8 13 VEE 9 N.C. SO QSOP ______________________________________________________________________________________ 13 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 _______________________________________________Pin Configurations (continued) __________________________________________________Tape-and-Reel Information D P0 W P2 B0 t D1 F P NOTE: DIMENSIONS ARE IN MM. AND FOLLOW EIA481-1 STANDARD. 3.988 0.102 40.005 0.203 P2 2.007 0.051 t 0.254 0.127 8.001 +0.305 -0.102 0.102 P0 3.505 0.051 P010 K0 1.397 0.102 P 3.988 0.102 3.200 0.102 B0 3.099 0.102 F D 1.499 +0.102 +0.000 D1 0.991 +0.254 +0.000 A0 K0 A0 E 1.753 W 5 SOT23-5 E 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 www.maxim-ic.com/packages.) SOT5L.EPS MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable 14 ______________________________________________________________________________________ High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable E y 0.500.1 8 INCHES DIM A A1 A2 b H c D e E H 0.60.1 1 L 1 0.60.1 S BOTTOM VIEW D MIN 0.002 0.030 MAX 0.043 0.006 0.037 0.010 0.014 0.005 0.007 0.116 0.120 0.0256 BSC 0.116 0.120 0.188 0.198 0.016 0.026 6 0 0.0207 BSC 8LUMAXD.EPS 4X S 8 MILLIMETERS MAX MIN 0.05 0.75 1.10 0.15 0.95 0.25 0.36 0.13 0.18 2.95 3.05 0.65 BSC 2.95 3.05 4.78 5.03 0.41 0.66 0 6 0.5250 BSC TOP VIEW A1 A2 e FRONT VIEW A c b L SIDE VIEW PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, 8L uMAX/uSOP APPROVAL DOCUMENT CONTROL NO. REV. J 1 1 SOICN.EPS 21-0036 ______________________________________________________________________________________ 15 MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 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 www.maxim-ic.com/packages.) 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 www.maxim-ic.com/packages.) QSOP.EPS MAX4214/MAX4215/MAX4217/MAX4219/MAX4222 High-Speed, Single-Supply, Gain of 2, Closed-Loop, Rail-to-Rail Buffers with Enable 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. 16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 (c) 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Maxim Integrated: MAX4222ESD+ MAX4214EUK+T MAX4215ESA+ MAX4215ESA+T MAX4215EUA+ MAX4215EUA+T MAX4217ESA+ MAX4217ESA+T MAX4217EUA+ MAX4217EUA+T MAX4219EEE+ MAX4219ESD+ MAX4219ESD+T MAX4222ESD+T MAX4219EEE+T MAX4222EEE+T MAX4222EEE+ MAX4214EUK+