Low-Cost, Low-Power, Ultra-Small, 3V/5V, 500MHz Single-Supply Op Amps with Rail-to-Rail Outputs

Transcription

1 9-83; Rev ; / Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz General Description The MAX442 single and MAX443 dual operational amplifiers are unity-gain-stable devices that combine high-speed performance, low supply current, and ultrasmall packaging. Both devices operate from a single +2.7V to +5.5V supply, have Rail-to Rail outputs, and exhibit a common-mode input voltage range that extends from mv below ground to within +.5V of the positive supply rail. The achieve a 5MHz -3dB bandwidth and a 22V/µs slew rate while consuming only.7ma of supply current per amplifier. This makes the ideal for low-power/low-voltage, high-speed portable applications such as video, communications, and instrumentation. For systems requiring tighter specifications, Maxim offers the MAX444 MAX449 family of operational amplifiers. The MAX444 MAX449 are laser trimmed versions of the and include compensated and uncompensated devices. The MAX442 is available in ultra-small 5-pin SC7 and SOT23 packages, while the MAX443 is available in a space-saving 8-pin SOT23. Applications Battery-Powered Instruments Portable Communications Keyless Entry Systems Cellular Telephones Video Line Drivers Baseband Applications Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd. Typical Operating Characteristic Features Ultra-Low.7mA Supply Current Low Cost Single +3V/+5V Operation High Speed 5MHz -3dB Bandwidth 5MHz.dB Gain Flatness 22V/µs Slew Rate Rail-to-Rail Outputs Input Common-Mode Range Extends Beyond V EE Low Differential Gain/Phase:.%/.3 Low Distortion at 5MHz -93dBc SFDR.3% Total Harmonic Distortion Ultra-Small SC7-5, SOT23-5, and SOT23-8 Packages PART TEMP. RANGE Ordering Information PIN- PACKAGE TOP M ARK MAX442EXK-T -4 C to +85 C 5 SC7-5 ABH MAX442EUK-T -4 C to +85 C 5 SOT23-5 ADOL MAX443EKA-T -4 C to +85 C 8 SOT23-8 AADR Pin Configurations 2..9 SUPPLY CURRENT vs. SUPPLY VOLTAGE (PER AMPLIFER) MAX442 toc TOP VIEW SUPPLY CURRENT (ma) SUPPLY VOLTAGE (V) OUT V EE IN+ V CC OUTB INB- INB+ OUTA INA- INA+ V EE MAX443 SOT V CC MAX IN- SC7/SOT23 Maxim Integrated Products For price, delivery, and to place orders, please contact Maxim Distribution at , or visit Maxim s website at

2 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz ABSOLUTE MAXIMUM RATINGS Supply Voltage (V CC to V EE )...+6V Differential Input Voltage...±2.5V IN_-, IN_+, OUT_...(V CC +.3V) to (V EE -.3V) Current into Input Pins...±2mA Output Short-Circuit Duration to V CC or V EE...Continuous Continuous Power Dissipation (T A = +7 C) 5-Pin SC7 (derate 3.mW/ C above +7 C)...247mW 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 5-Pin SOT23 (derate 7.mW/ C above +7 C)...57mW 8-Pin SOT23 (derate 9.mW/ C above +7 C)...727mW Operating Temperature Range...-4 C to +85 C Junction Temperature...+5 C Storage Temperature Range C to +5 C Lead Temperature (soldering, s)...+3 C (V CC = +2.7V to +5.5V, V CM = V CC /2 -.75V, V EE =, R L = to V CC /2, V OUT = V CC /2, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Supply Voltage Range V S Guaranteed by PSRR test V Quiescent Supply Current (per amplifier) Input Common Mode Voltage Range V CC = +5V I S V CC = +3V.5 V CM Guaranteed by CMRR test Input Offset Voltage V OS.4 9 mv Input Offset Voltage Temperature Coefficient V EE -. V CC -.5 TC VOS 3 µv/ C Input Offset Voltage Matching MAX443 ± mv Input Bias Current I B.6 4 µa Input Offset Current I OS..7 µa Differential mode, -.4V (V IN+ - V IN- ) +.4V Input Resistance R IN Common mode, V EE -.V < V CM < V CC -.5V ma V 6 kω 6 MΩ Common Mode Rejection Ratio CMRR V EE -.V < V CM < V CC -.5V 6 94 db Open-Loop Gain A VOL V CC = +5V V CC = +3V +.2V V OUT +4.8V, R L = kω +.4V V OUT +4.6V, R L = kω +V V OUT +4V, R L = 5Ω +.2V V OUT +2.8V, R L = kω +.25V V OUT +2.75V R L = kω +.5V V OUT +2.5V, R L = 5Ω db 2

3 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz DC ELECTRICAL CHARACTERISTICS (continued) (V CC = +2.7V to +5.5V, V CM = V CC /2 -.75V, V EE =, R L = to V CC /2, V OUT = V CC /2, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage Swing V OUT V CC = +5V V CC = +3V V CC - V OH.85 R L = kω VOL - V EE.5 R L = kω V CC - V OH V OL - V EE R L = V CC - V OH.385 5Ω V OL - V EE.5 V CC - V OH.6 R L = kω VOL - V EE. R L = kω V CC - V OH.75 V OL - V EE.25 R L = V CC - V OH.275 5Ω V OL - V EE.7 Output Current I OUT R L = 2Ω connected to V C C or V E E, V C C = + 5V ±25 ±75 ma Output Short-Circuit Current I SC Sinking or sourcing ±85 ma Power Supply Rejection Ratio PSRR V CC = +2.7V to +5.5V, V CM =, V OUT = 2V 6 77 db V AC ELECTRICAL CHARACTERISTICS (V CC = +5V, V EE =, V CM = +.75V, R L = kω connected to V CC /2, C L = 5pF, A VCL = +V/V, T A = +25 C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Small Signal -3dB Bandwidth BW SS V OU T = mv p - p 5 MHz Large Signal -3dB Bandwidth BW LS V OUT = 2Vp-p 3 MHz V OUT = mvp-p 5 Bandwidth for.db Flatness BW.dB V OUT = 2Vp-p 6 Slew Rate SR V OUT = 2V step 22 V/µs Rise/Fall Time t R, t F V OUT = 2V step, % to 9% 4 ns Settling Time to.% t S % V OUT = 2V step ns MHz Spurious-Free Dynamic Range SFDR V CC = +5V, f C = 5MHz, V OUT = Vp-p -84 V CC = +3V, f C = 5MHz, V OUT = Vp-p -93 dbc 3

4 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz AC ELECTRICAL CHARACTERISTICS (continued) (V CC = +5V, V EE =, V CM = +.75V, R L = kω connected to V CC /2, C L = 5pF, A VCL = +V/V, T A = +25 C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 2 nd Harmonic Distortion 3 rd Harmonic Distortion Total Harmonic Distortion Two-Tone, Third-Order Intermodulation Distortion THD Differential Gain Error DG R L = 5Ω, NTSC Differential Phase Error DP R L = 5Ω, NTSC V CC = +5V, f C = 5MHz, V OUT = Vp-p -84 V CC = +3V, f C = 5MHz, V OUT = Vp-p -93 V CC = +5V, f C = 5MHz, V OUT = Vp-p -95 V CC = +3V, f C = 5MHz, V OUT = Vp-p -95 V CC = +5V, f C = 5MHz, V OUT = Vp-p.7 V CC = +3V, f C = 5MHz, V OUT = Vp-p.3 IP3 f = MHz, f 2 = 9.9MHz -67 dbc A V = +V/V.3 A V = +2V/V. A V = +V/V.3 A V = +2V/V.3 Gain Matching MAX443, V OUT = mvp-p, f MHz. db dbc dbc % % d egr ees Phase Matching MAX443, V OUT = mvp-p f MHz. d egr ees Input Noise-Voltage Density e n f = khz 3 nv/ Hz Input Noise-Current Density I n f = khz.7 p A/ Hz Input Capacitance C IN.8 pf Output Impedance Z OUT f = MHz.7 Ω Capacitive Load Drive No sustained oscillations 2 pf Power-Up % Settling Time (Note 2).2 µs Crosstalk X TALK M AX443, f = M H z, V OU T = 2V p -p -82 db Note : All devices are % production tested at T A = +25 C. Specifications over temperature are guaranteed by design. Note 2: Guaranteed by design. 4

5 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz SUPPLY CURRENT (ma) Typical Operating Characteristics (V CC = +5V, V EE =, V CM = +.75V, A VCL = +V/V, R F = 24Ω, R L = kω to V CC /2, C L = 5pF, T A = +25 C, unless otherwise noted.) SUPPLY CURRENT vs. SUPPLY VOLTAGE (PER AMPLIFER) SUPPLY VOLTAGE (V) MAX442 toc SMALL-SIGNAL GAIN (db) SMALL-SIGNAL GAIN vs. FREQUENCY -7 k M M M G MAX442 toc2 SMALL-SIGNAL GAIN (db) SMALL-SIGNAL GAIN with CAPACATIVE LOAD vs. FREQUENCY pF 5pF 5pF -6 k M M M G MAX442 toc3 SMALL-SIGNAL GAIN (db) SMALL-SIGNAL GAIN with CAPACITIVE LOAD and 22Ω ISOLATION RESISTOR vs. FREQUENCY pF 5pF 5pF -5 k M M M G MAX442 toc4 GAIN FLATNESS (db) SMALL-SIGNAL GAIN FLATNESS vs. FREQUENCY -.5 k M M M G MAX442 toc5 LARGE-SIGNAL GAIN (db) LARGE-SIGNAL GAIN FLATNESS vs. FREQUENCY V OUT = 2V P-P V OUT = V P-P -.5 k M M M G MAX442 toc6 LARGE-SIGNAL GAIN (db) LARGE-SIGNAL GAIN vs. FREQUENCY V OUT = 2V P-P V OUT = V P-P -7 k M M M G MAX442 toc7 GAIN (db) GAIN AND PHASE vs. FREQUENCY MAX442 toc9 8 A VCL = +V/V 35 9 GAIN 45 PHASE k K M M M G PHASE (deg) DIFFERENTIAL GAIN (%) DIFFERENTIAL PHASE (deg) DIFFERENTIAL GAIN AND PHASE IRE IRE MAX442 toc 5

6 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz Typical Operating Characteristics (continued) (V CC = +5V, V EE =, V CM =.75V, A VCL = +V/V, R F = 24Ω, R L = kω to V CC /2, C L = 5pF, T A = +25 C, unless otherwise noted.) INPUT 5mV/div OUTPUT 5mV/div SMALL-SIGNAL PULSE RESPONSE R L = kω 5ns/div MAX442 toc INPUT 5mV/div OUTPUT 5mV/div LARGE-SIGNAL PULSE RESPONSE R L = kω 5ns/div MAX442 toc2 INPUT V/div OUTPUT V/div LARGE-SIGNAL PULSE RESPONSE R L = kω 5ns/div MAX442 toc3 SMALL-SIGNAL PULSE RESPONSE LARGE-SIGNAL PULSE RESPONSE SMALL-SIGNAL PULSE RESPONSE (C L = 5pF) INPUT 5mV/div MAX442 toc4 INPUT 5mV/div MAX442 toc5 INPUT 5mV/div MAX442 toc6 OUTPUT 5mV/div OUTPUT 5mV/div OUTPUT 5mV/div R L = 5Ω R L = 5Ω 5ns/div 5ns/div 5ns/div OUTPUT IMPEDANCE (Ω) CLOSED-LOOP OUTPUT IMPEDANCE vs. FREQUENCY. k M M M G MAX442 toc7 CROSSTALK (db) MAX443 CROSSTALK vs. FREQUENCY - k M M M G MAX442 toc8 BANDWIDTH (MHz) SMALL SIGNAL BANDWIDTH vs. LOAD RESISTANCE R LOAD (Ω) MAX442 toc9 6

7 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz Typical Operating Characteristics (continued) (V CC = +5V, V EE =, V CM =.75V, A VCL = +V/V, R F = 24Ω, R L = kω to V CC /2, C L = 5pF, T A = +25 C, unless otherwise noted.) OPEN-LOOP GAIN (db) OPEN-LOOP GAIN vs. LOAD RESISTANCE k k k R LOAD (Ω) MAX442 toc2 OUTPUT VOLTAGE SWING (mv) OUTPUT VOLTAGE SWING vs. LOAD RESISTANCE V OH V OL k k R LOAD (Ω) MAX442 toc2 PSR (db) POWER SUPPLY REJECTION vs. FREQUENCY - k M M M G MAX442 toc22 CMR (db) COMMON-MODE REJECTION vs. FREQUENCY MAX442 toc23 VOLTAGE NOISE DENSITY nv/ Hz VOLTAGE NOISE DENSITY vs. FREQUENCY MAX442 toc24 CURRENT NOISE DENSITY pa/ Hz CURRENT NOISE DENSITY vs. FREQUENCY MAX442 toc25 - k M M M G k k k M k k k M DISTORTION (dbc) HARMONIC DISTORTION vs. FREQUENCY V OUT = V p-p 2nd HARMONIC MAX442 toc26 DISTORTION (dbc) f = 5MHz HARMONIC DISTORTION vs. OUTPUT VOLTAGE 2nd HARMONIC MAX442 toc27 DISTORTION (dbc) HARMONIC DISTORTION vs. LOAD RESISTENCE V OUT = V p-p, f = 5MHz 2nd HARMONIC MAX442 toc28-3rd HARMONIC -95 3rd HARMONIC - 3rd HARMONIC -2 K M M M OUTPUT VOLTAGE (V p-p ) K K R LOAD (Ω) 7

8 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz Typical Operating Characteristics (continued) (V CC = +5V, V EE =, V CM =.75V, A VCL = +V/V, R F = 24Ω, R L = kω to V CC /2, C L = 5pF, T A = +25 C, unless otherwise noted.) RISO (Ω) ISOLATION RESISTANCE vs. CAPACITIVE LOAD C LOAD (pf) MAX442 toc29 V SUPPLY 2.V/div V OUT 75mV/div POWER-UP RESPONSE TIME 5ns/div MAX442 toc3 +5V +.5V SUPPLY CURRENT (ma) SUPPLY CURRENT (PER AMPLIFIER) vs. TEMPERATURE TEMPERATURE ( C) MAX442 toc3 INPUT BIAS CURRENT (µa) INPUT OFFSET VOLTAGE (mv) INPUT BIAS CURRENT vs. TEMPERATURE TEMPERATURE ( C) INPUT OFFSET VOLTAGE vs. TEMPERATURE TEMPERATURE ( C) MAX442 toc32 MAX442 toc34 INPUT OFFSET CURRENT (na) OUTPUT VOLTAGE SWING (mv) INPUT OFFSET CURRENT vs. TEMPERATURE TEMPERATURE ( C) OUTPUT VOLTAGE SWING vs. TEMPERATURE V OH = V CC - V OUT V OL = V OUT - V EE TEMPERATURE ( C) MAX442 toc33 MAX442 toc35 8

9 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz PIN MAX442 MAX443 NAME OUT Amplifier Output OUTA Amplifier A Output 7 OUTB Amplifier B Output 2 4 V EE Negative Power Supply 3 IN+ Amplifier Noninverting Input 3 INA+ Amplifier A Noninverting Input 5 INB+ Amplifier B Noninverting Input 4 IN- Amplifier Inverting Input 2 INA- Amplifier A Inverting Input 6 INB- Amplifier B Inverting Input 5 8 V CC Positive Power Supply FUNCTION Pin Description Detailed Description The single-supply, rail-to-rail, voltage-feedback amplifiers achieve 22V/µs slew rates and 5MHz -3dB bandwidths, while consuming only.7ma of supply current per amplifier. Excellent harmonic distortion and differential gain/phase performance make these amplifiers an ideal choice for a wide variety of video and RF signal-processing applications. Internal feedback around the output stage ensures low open-loop output impedance, reducing gain sensitivity to load variations. This feedback also produces demand-driven current bias to the output transistors. Rail-to-Rail Outputs, Ground-Sensing Input The input common-mode range extends from (V EE -.V) to (V CC -.5V) with excellent common-mode rejection. Beyond this range, the amplifier output is a nonlinear function of the input, but does not undergo phase reversal or latchup. The output swings to within 5mV of either power-supply rail with a kω load. Input ground sensing and railto-rail outputs substantially increase the dynamic range. With a symmetric input in a single +5V application, the input can swing 3.6Vp-p, and the output can swing 4.6Vp-p with minimal distortion. Output Capacitive Loading and Stability The are optimized for AC performance. They are not designed to drive highly reactive loads. Such loads decrease phase margin and may produce excessive ringing and oscillation. The use of an isolation resistor eliminates this problem (Figure ). Figure 2 is a graph of the Optimal Isolation Resistor (R ISO ) vs. Capacitive Load. The Small Signal Gain vs. Frequency with Capacitive Load and No Isolation Resistor graph in the Typical Operating Characteristics shows how a capacitive load causes excessive peaking of the amplifier s frequency response if the capacitor is not isolated from the amplifier by a resistor. A small isolation resistor (usually 2Ω to 3Ω) placed before the reactive load prevents ringing and oscillation. At higher capacitive loads, AC performance is controlled by the interaction of the load capacitance and the isolation resistor. The Small-Signal Gain vs. Frequency with Capacitive Load and 22Ω Isolation Resistor graph shows the effect of a 22Ω isolation resistor on closed-loop response. Coaxial cable 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 line s capacitance. Applications Information Choosing Resistor Values Unity-Gain Configuration The are internally compensated for unity gain. When configured for unity gain, the devices require a 24Ω feedback resistor (R F ). This resistor improves AC response by reducing the Q of the parallel LC circuit formed by the parasitic feedback capacitance and inductance. 9

10 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz Inverting and Noninverting Configurations Select the gain-setting feedback (R F ) and input (R G ) resistor values that best fit the application. Large resistor values increase voltage noise and interact with the amplifier s input and PC board capacitance. This can generate undesirable poles and zeros and decrease bandwidth or cause oscillations. For example, a noninverting gain-of-two configuration (R F = R G ) using kω resistors, combined with.8pf of amplifier input capacitance and pf of PC board capacitance, causes a pole at 4MHz. Since this pole is within the amplifier bandwidth, it jeopardizes stability. Reducing the kω resistors to Ω extends the pole frequency to.4ghz, but could limit output swing by adding 2Ω in parallel with the amplifier s load resistor. Note: For high-gain applications where output offset voltage is a consideration, choose R S to be equal to the parallel combination of R F and R G (Figures 3a and 3b): RS = RF RF Video Line Driver The are designed to minimize differential gain error and differential phase error to.%/.3 respectively, making them ideal for driving video loads. Active Filters The low distortion and high bandwidth of the make them ideal for use in active filter circuits. Figure 4 is a 5MHz lowpass, multiplefeedback active filter using the MAX442. GAIN + = RG RG R2 R R G R F R ISO V OUT R G R F V IN C L R BIN V OUT IN R S R V OUT = [+ (R F / R G )] V IN Figure. Driving a Capacitive Load Through an Isolation Resistor RISO (Ω) ISOLATION RESISTANCE vs. CAPACITIVE LOAD MAX442 toc29 Figure 3a. Noninverting Gain Configuration R G R F IN V OUT 6 4 V OUT = (R F / R G ) V IN R O 2 R S C LOAD (pf) Figure 2. Isolation Resistance vs. Capacitive Load Figure 3b. Inverting Gain Configuration

11 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz f = 2π Q = R2 R3 C C2 C2 C C2 R2 R3 + + R R2 R3 ADC Input Buffer Input buffer amplifiers can be a source of significant errors in high-speed analog-to-digital converter (ADC) applications. The input buffer is usually required to rapidly charge and discharge the ADC s input, which is often capacitive (see Output Capacitive Loading and Stability). In addition, since a high-speed ADC s input impedance often changes very rapidly during the conversion cycle, measurement accuracy must be maintained using an amplifier with very low output impedance at high frequencies. The combination of high speed, fast slew rate, low noise, and a low and stable distortion overload makes the MAX442/ MAX443 ideally suited for use as buffer amplifiers in high-speed ADC applications. Layout and Power-Supply Bypassing These amplifiers operate from a single +2.7V to +5.5V power supply. Bypass V CC to ground with a.µf capacitor as close to the pin as possible. Maxim recommends using microstrip and stripline techniques to obtain full bandwidth. Design the PC board for a frequency greater than GHz to prevent amplifier performance degradation due to board parasitics. Avoid large parasitic capacitances at inputs and outputs. Whether or not a constant-impedance board is used, observe the following guidelines: Do not use wire-wrap boards due to their high inductance. Do not use IC sockets because of the increased parasitic capacitance and inductance. Use surface-mount instead of through-hole components 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 possible. Do not make 9 turns; round all corners.

12 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz V IN R 5Ω R2 5Ω C pf R3 5Ω C2 5pF k k +5.V MAX442 V OUT Figure 4. Multiple-Feedback Lowpass Filter _ Chip Information MAX442 TRANSISTOR COUNT: 99 MAX443 TRANSISTOR COUNT: 92 PROCESS: Bipolar 2

13 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz Package Information SC7, 5L.EPS 3

14 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz Package Information (continued) SOT5L.EPS 4

15 Low-Cost, Low-Power, Ultra-Small, 3V/5V, 5MHz Package Information (continued) SOT23, 8L.EPS 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. Maxim Integrated Products, 2 San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.