19-2164; Rev 0; 10/01 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 The MAX4230 comes in a tiny 5-pin SC70 package and the MAX4231, single with shutdown, is offered in the 6-pin SC70 package. The dual op amp MAX4233 is offered in the space-saving 10-bump UCSP™, providing the smallest footprint area for a dual op amp with shutdown. These op amps are designed to be part of the PA control circuitry, biasing RF PAs in wireless headsets. The MAX4231/MAX4233 offer a SHDN feature that drives the output low. This ensures that the RF PA is fully disabled when needed, preventing unconverted signals to the RF antenna. Features ♦ 30mA Output Drive Capability ♦ Rail-to-Rail Input and Output ♦ 1.1mA Supply Current per Amplifier ♦ +2.7V to +5.5V Single-Supply Operation ♦ 10MHz Gain-Bandwidth Product ♦ High Slew Rate: 10V/µs ♦ 100dB Voltage Gain (RL = 100kΩ) ♦ 85dB Power-Supply Rejection Ratio ♦ No Phase Reversal for Overdriven Inputs ♦ Unity-Gain Stable for Capacitive Loads to 780pF ♦ Low-Power Shutdown Mode Reduces Supply Current to <1µA ♦ Available in 5-Pin SC70 Package (MAX4230) ♦ Available in 10-Bump UCSP Package (MAX4233) The MAX4230 family offers low offsets, wide bandwidth, and high output drive in a tiny 2.1mm x 2.0mm SC70 space-saving package. These parts are offered over the automotive temperature range (-40°C to +125°C) Ordering Information TEMP. RANGE PART Applications TOP MARK PINPACKAGE MAX4230AXK-T -40°C to +125°C 5 SC70-5 ACS RF PA Biasing Controls in Handset Applications MAX4230AUK-T -40°C to +125°C 5 SOT23-5 ABZZ Portable/Battery-Powered Audio Applications MAX4231AXT-T -40°C to +125°C 6 SC70-6 ABA MAX4231AUT-T -40°C to +125°C 6 SOT23-6 Portable Headphone Speaker Drivers (32Ω) Audio Hands-Free Car Phones (Kits) AAUV Ordering Information continued at end of data sheet. Laptop/Notebook Computers/TFT Panels Typical Operating Circuit Sound Ports/Cards Set-Top Boxes ANTENNA Digital-to-Analog Converter Buffers Transformer/Line Drivers Motor Drivers 2.7V TO 5.5V PA IOUT = 30mA DAC RISO MAX4231 SHDN Selector Guide appears at end of data sheet. Pin Configurations appear at end of data sheet. CLOAD C R RF Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd. UCSP is a trademark of Maxim Integrated Products, Inc. ________________________________________________________________ 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 MAX4230–MAX4234 General Description The MAX4230–MAX4234 single/dual/quad, high-output drive CMOS op amps feature 200mA of peak output current, Rail-to-Rail® input, and output capability from a single +2.7V to +5.5V supply. These amplifiers exhibit a high slew rate of 10V/µs and a gain-bandwidth product of 10MHz. The MAX4230–MAX4234 can drive typical headset levels (32Ω), as well as bias an RF power amplifier (PA) in wireless handset applications. MAX4230–MAX4234 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 ABSOLUTE MAXIMUM RATINGS Supply Voltage (VDD to VSS)..................................................+6V All Other Pins ....................................(VSS - 0.3V) + (VDD + 0.3V) Output Short-Circuit Duration to VDD or VSS (Note 1) ..................1s Continuous Power Dissipation (TA = +70°C) 5-Pin SC70 (derate 3.1mW/°C above +70°C) ..............247mW 5-Pin SOT23 (derate 7.1mW/°C above +70°C)...........571mW 6-Pin SC70 (derate 3.1mW/°C above +70°C) ..............245mW 6-Pin SOT23 (derate 8.7mW/°C above +70°C) ...........696mW 8-Pin SOT23 (derate 8.9mW/°C above +70°C) ...........714mW 8-Pin µMAX (derate 4.5mW/°C above +70°C) ............362mW 10-Pin µMAX (derate 5.6mW/°C above +70°C) ..........444mW 10-Bump UCSP (derate 6.1mW/°C above +70°C) .....484mW 14-Pin TSSOP (derate 9.1mW/°C above +70°C) ........727mW 14-Pin SO (derate 8.3mW/°C above +70°C) ...............667mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Note 1: Package power dissipation should also be observed. 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 (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = (VDD/2), RL = ∞ connected to (VDD/2), V SHDN = VDD, TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL Operating Supply Voltage Range VDD Input Offset Voltage VOS Input Bias Current CONDITIONS MIN Inferred from PSRR test TYP 2.7 0.85 MAX UNITS 5.5 V ±3 mV IB VCM = VSS to VDD 50 pA Input Offset Current IOS VCM = VSS to VDD 50 pA Input Resistance RIN 1000 MΩ Common-Mode Input Voltage Range VCM Inferred from CMRR test VSS VDD Common-Mode Rejection Ratio CMRR VSS < VCM < VDD 55 Power-Supply Rejection Ratio PSRR VDD = +2.7V to +5.5V 75 Shutdown Output Impedance ROUT V SHDN = 0 (Note 3) 10 VOUT(SHDN) V SHDN = 0, RL = 200Ω (Note 3) RL = 100kΩ VSS + 0.20 < VOUT AVOL RL = 2kΩ < VDD - 0.20V RL = 200Ω 68 Output Voltage in Shutdown Large-Signal Voltage Gain RL = 32Ω Output Voltage Swing VOUT RL = 200Ω RL = 2kΩ Output Source/Sink Current 2 dB 85 dB Ω 120 85 98 74 80 VDD - VOH 400 500 360 500 VDD - VOH 80 120 VOL - VSS 70 120 VDD - VOH 8 14 VOL - VSS 7 14 VDD = +2.7V VDD = +5V mV dB VOL - VSS Output Voltage with Current Load IL = 30mA 70 100 VOUT = 0.15V to (VDD - 0.15V) IL = 10mA V 7 10 mA VDD - VOH 128 200 VOL - VSS 112 175 VDD - VOH 240 320 VOL - VSS 224 300 _______________________________________________________________________________________ mV mV High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = (VDD/2), RL = ∞ connected to (VDD/2), V SHDN = VDD, TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL Quiescent Supply Current (per Amplifier) IDD Shutdown Supply Current (per Amplifier) (Note 3) IDD(SHDN) SHDN Logic Threshold SHDN Input Bias Current TYP MAX VDD = +5.5V, VCM = VDD / 2 CONDITIONS 1.2 2.3 VDD = +2.7V, VCM = VDD / 2 1.1 2.0 VDD = +5.5V 0.5 1 VDD = +2.7V 0.1 1 V SHDN = 0, RL = ∞ MIN Shutdown mode (Note 3) VSS + 0.3 Normal mode (Note 3) VDD - 0.3 VSS < V S HDN < VDD (Note 3) UNITS mA µA V 50 pA DC ELECTRICAL CHARACTERISTICS (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = (VDD/2), RL = ∞ connected to (VDD/2), V SHDN = VDD, TA = -40 to +125°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL Operating Supply Voltage Range VDD Input Offset Voltage CONDITIONS MIN Inferred from PSRR test TYP 2.7 Common-Mode Input Voltage Range VCM Common-Mode Rejection Ratio Power-Supply Rejection Ratio Output Voltage in Shutdown Large-Signal Voltage Gain Inferred from CMRR test 50 PSRR VDD = +2.7V to +5.5V 70 V SHDN < 0, RL = 200Ω (Note 3) VSS + 0.2V < VDD - 0.2V RL = 32Ω, TA = +85°C Output Voltage Swing VOUT RL = 200Ω RL = 2kΩ Output Source/Sink Current Output Voltage with Current VSS VSS < VCM < VDD AVOL V 80 RL = 200Ω 70 IL = 10mA VDD = +2.7V IL = 30mA, TA = -40°C VDD = +5V mV µV/°C VDD V dB dB 150 RL = 2kΩ mV dB VDD - VOH 650 VOL - VSS 650 VDD - VOH 150 VOL - VSS 150 VDD - VOH 20 VOL - VSS 20 VOUT = 0.15V to (VDD - 0.15V) Load 5.5 ±3 CMRR VOUT(SHDN) UNITS ±5 VOS ∆VOS / ∆T Offset Voltage Tempco MAX 4 mV mA VDD - VOH 250 VOL - VSS 230 VDD - VOH 400 mV _______________________________________________________________________________________ 3 MAX4230–MAX4234 DC ELECTRICAL CHARACTERISTICS (continued) MAX4230–MAX4234 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 DC ELECTRICAL CHARACTERISTICS (continued) (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = (VDD/2), RL = ∞ connected to (VDD/2), V SHDN = VDD, TA = -40 to +125°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL Quiescent Supply Current (per Amplifier) IDD Shutdown Supply Current (per Amplifier) (Note 3) IDD(SHDN) CONDITIONS MIN TYP MAX VDD = +5.5V, VCM = VDD / 2 2.8 VDD = +2.7V, VCM = VDD / 2 2.5 V SHDN < 0, RL = ∞ VDD = +5.5V 2.0 VDD = +2.7V 2.0 UNITS mA µA AC ELECTRICAL CHARACTERISTICS (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = (VDD/2), RL = ∞ connected to (VDD/2), V SHDN = VDD, TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Gain-Bandwidth Product GBWP VCM = VDD / 2 10 MHz Full-Power Bandwidth FPBW VOUT = 2Vp-p, VDD = +5V 0.8 MHz Slew Rate SR 10 V/µs Phase Margin PM 70 Degrees Gain Margin GM 15 dB 0.0005 % 8 pF Total Harmonic Distortion Plus Noise Input Capacitance Voltage Noise Density THD+N CIN en Channel-to-Channel Isolation Capacitive Load Stability Shutdown Time Enable Time from Shutdown Power-Up Time f = 10kHz, VOUT = 2Vp-p, AVCL = +1V/V f = 1kHz 15 f = 10kHz 12 f = 1kHz, RL = 100kΩ 125 dB AVCL = +1V/V, no sustained oscillations 780 pF tSHDN (Note 3) 1 µs tENABLE (Note 3) 1 µs 5 µs tON Note 2: All units 100% tested at +25°C. All temperature limits are guaranteed by design. Note 3: SHDN logic parameters are for MAX4231/MAX4233 only. 4 nV/√Hz _______________________________________________________________________________________ High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 GAIN AND PHASE vs. FREQUENCY (CL = 250pF) MAX4230 toc01 90 90 50 60 50 60 30 40 30 30 0 20 -30 10 -60 GAIN (dB) 60 60 PHASE (Degrees) 70 40 GAIN (dB) MAX4230 toc02 120 70 30 0 20 -30 10 -60 -90 -120 -10 -150 -20 AV = +1000V/V -30 0.01k 0.1k 1k 10k 100k 1M -90 0 0 -10 -20 -30 0.01k 0.1k -180 10M 100M 1k -150 10k 100k 1M -180 10M 100M FREQUENCY (Hz) POWER-SUPPLY REJECTION RATIO vs. FREQUENCY OUTPUT IMPEDANCE vs. FREQUENCY -10 OUTPUT IMPEDANCE (Ω) -20 -30 -40 -50 -60 -70 -80 MAX4230 toc04 1000 MAX4230 toc03 0 100 10 1 0.1 AV = +1V/V -90 -100 0.01k AV = +1V/V 0.01 0.1k 1k 10k 100k 1M 10M 1k 10k 100k 1M 10M FREQUENCY (Hz) FREQUENCY (Hz) SUPPLY CURRENT vs. TEMPERATURE SUPPLY CURRENT vs. TEMPERATURE (SHDN = LOW) 110 MAX4230 toc05 2.0 1.8 100 SUPPLY CURRENT (nA) 1.6 1.4 1.2 1.0 0.8 0.6 0.4 MAX4230 toc06 PSRR (dB) -120 AV = +1000V/V CL = 250pF FREQUENCY (Hz) SUPPLY CURRENT (mA) 120 PHASE (Degrees) GAIN AND PHASE vs. FREQUENCY 90 80 70 60 SHDN = VSS 0.2 50 0 -40 -20 0 20 40 60 80 TEMPERATURE (°C) 100 120 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) _______________________________________________________________________________________ 5 MAX4230–MAX4234 __________________________________________Typical Operating Characteristics (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = VDD/2, RL = ∞, connected to VDD/2, V SHDN = VDD. TA = +25°C, unless otherwise noted.) ____________________________Typical Operating Characteristics (continued) (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = VDD/2, RL = ∞, connected to VDD/2, V SHDN = VDD. TA = +25°C, unless otherwise noted.) 1.8 1.6 MAX4230 toc08 2 MAX4230 toc07 2.0 VDD = +2.7V 1.0 80 VDD - VOUT (mV) 1.2 VDD = +5.0V 0 0.8 0.6 VDD = +5.0V RL = 200Ω 100 1 1.4 VOS (mV) SUPPLY CURRENT (mA) OUTPUT SWING HIGH vs. TEMPERATURE INPUT OFFSET VOLTAGE vs. TEMPERATURE MAX4230/34 toc09 SUPPLY CURRENT PER AMPLIFIER vs. SUPPLY VOLTAGE VDD = +2.7V RL = 200Ω 60 40 -1 0.4 20 0.2 0 -2 3.0 3.5 4.0 4.5 5.0 20 40 60 80 100 120 -40 -20 20 40 60 100 120 80 OUTPUT SWING LOW vs. TEMPERATURE INPUT OFFSET VOLTAGE vs. COMMON-MODE VOLTAGE SUPPLY CURRENT PER AMPLIFIER vs. COMMON-MODE VOLTAGE 80 60 VDD = +2.7V RL = 200Ω 40 1.2 0.5 1.0 0 -0.5 -1.0 0 20 40 60 80 0 100 120 0.6 VDD = +2.7V 0.2 -2.0 0 0.8 0.4 -1.5 20 MAX4230/3 toc12 1.0 SUPPLY CURRENT (mA) MAX4230/3 toc10 VDD = +5.0V RL = 200Ω -40 -20 0 TEMPERATURE (°C) 0.5 1.5 1.0 2.0 0 2.5 0.5 1.5 1.0 2.0 2.5 COMMON-MODE VOLTAGE (V) COMMON-MODE VOLTAGE (V) SUPPLY CURRENT PER AMPLIFIER vs. COMMON-MODE VOLTAGE TOTAL HARMONIC DISTORTION + NOISE vs. FREQUENCY TOTAL HARMONIC DISTORTION + NOISE vs. PEAK-TO-PEAK OUTPUT VOLTAGE 0.45 MAX4230/34 toc13 1.4 1.2 VOUT = 2Vp-p 500kHz LOWPASS FILTER 0.40 10 0.35 f = 10kHz VDD = +5V 0.8 0.6 VDD = +5.0V 0.4 0.30 THD + NOISE (%) THD + NOISE (%) 1 1.0 0.25 0.20 0.15 RL = 32Ω 0.10 RL = 25Ω RL = 2kΩ RL = 100kΩ MAX4230/34 toc15 TEMPERATURE (°C) MAX4230/34 toc14 VOUT - VSS (mV) 0 TEMPERATURE (°C) 100 RL = 250Ω 0.1 0.001 0.05 RL = 10kΩ 0 0.2 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 COMMON-MODE VOLTAGE (V) 6 -20 SUPPLY VOLTAGE (V) 140 120 0 -40 5.5 MAX4230/3 toc11 2.5 INPUT OFFSET VOLTAGE (mV) 2.0 SUPPLY CURRENT (mA) MAX4230–MAX4234 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 10 100 1k FREQUENCY (Hz) 10k 100k 0.0001 4.0 4.2 4.4 4.6 PEAK-TO-PEAK (V) _______________________________________________________________________________________ 4.8 5.0 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 SMALL-SIGNAL TRANSIENT RESPONSE (NONINVERTING) LARGE-SIGNAL TRANSIENT RESPONSE (NONINVERTING) SMALL-SIGNAL TRANSIENT RESPONSE (INVERTING) MAX4230/34 toc18 MAX4230/34 toc17 MAX4230/34 toc16 IN IN IN 50mV/div 50mV/div 1V/div OUT OUT OUT 1V/div OUT 60 50 40 30 -50 -70 -80 50 OUTPUT VOLTAGE (V) 4.5 5.0 0.6 0.8 1.0 1.2 INPUT VOLTAGE NOISE vs. FREQUENCY VDIFF = 100mV MAX4230/34 toc23 OUTPUT CURRENT vs. OUTPUT VOLTAGE (SINKING, VDD = +5.0V) -100 -150 -250 4.0 0.4 OUTPUT VOLTAGE (V) -200 0 0.2 0 0.5 1.0 1.5 2.0 OUTPUT VOLTAGE (V) 2.5 3.0 1.4 1.6 200 100 INPUT VOLTAGE NOISE (nV/√Hz) 100 0 OUTPUT VOLTAGE (V) -50 OUTPUT CURRENT (mA) 150 3.5 -40 10 0 MAX4230/34 toc22 200 3.0 -30 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 VDIFF = 100mV 2.5 -20 -60 OUTPUT CURRENT vs. OUTPUT VOLTAGE (SOURCING, VDD = +5.0V) 2.0 VDIFF = 100mV -10 20 0 400ns/div MAX4230/34 toc21 OUTPUT CURRNET (mA) 70 0 OUTPUT CURRENT (mA) IN VDIFF = 100mV MAX4230/34 toc20 80 250 OUTPUT CURRENT vs. OUTPUT VOLTAGE (SINKING, VDD = +2.7V) OUTPUT CURRENT vs. OUTPUT VOLTAGE (SOURCING, VDD = +2.7V) MAX4230/34 toc19 MAX4230/34 toc24 LARGE-SIGNAL TRANSIENT RESPONSE (INVERTING) OUTPUT CURRENT (mA) 400ns/div 400ns/div 400ns/div 10 100 1k 10k 100k FREQUENCY (Hz) _______________________________________________________________________________________ 7 MAX4230–MAX4234 ____________________________Typical Operating Characteristics (continued) (VDD = +2.7V, VSS = 0, VCM = VDD/2, VOUT = VDD/2, RL = ∞, connected to VDD/2, V SHDN = VDD. TA = +25°C, unless otherwise noted.) High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 MAX4230–MAX4234 Pin Description PIN FUNCTION MAX4231 MAX4232 MAX4233 MAX4234 1 1 — — — IN+ Noninverting Input 2 2 4 4 4 VSS Negative Supply Input. Connect to ground for single-supply operation. 3 3 — — — IN- Inverting Input 4 4 — — — OUT Amplifier Output 5 6 8 10 11 VDD Positive Supply Input — 5 — 5, 6 — SHDN1, SHDN2 — — 3 3 3 IN1+ Noninverting Input to Amplifier 1 — — 2 2 2 IN1- Inverting Input to Amplifier 1 — — 1 1 1 OUT1 Amplifier 1 Output — — 5 7 5 IN2+ Noninverting Input to Amplifier 2 — — 6 8 6 IN2- Inverting Input to Amplifier 2 — — 7 9 7 OUT2 Amplifier 2 Output Noninverting Input to Amplifiers 3 and 4 Shutdown Control. Tie to high for normal operation. — — — — 10, 12 IN3+, IN4+ — — — — 9, 13 IN3-, IN4- 8, 14 OUT3, OUT4 — — — — Detailed Description Rail-to-Rail Input Stage The MAX4230–MAX4234 CMOS operational amplifiers have parallel-connected N- and P-channel differential input stages that combine to accept a common-mode range extending to both supply rails. The N-channel stage is active for common-mode input voltages typically greater than (V SS + 1.2V), and the P-channel stage is active for common-mode input voltages typically less than (VDD - 1.2V). Applications Information Package Power Dissipation Warning: Due to the high output current drive, this op amp can exceed the absolute maximum power-dissipation rating. As a general rule, as long as the peak current is less than or equal to 40mA, the maximum package power dissipation is not exceeded for any of the package types offered. There are some exceptions to this rule, however. The absolute maximum power-dissipation rating of each package should always be verified using the fol- 8 NAME MAX4230 Inverting Input to Amplifiers 3 and 4 Amplifiers 3 and 4 Outputs lowing equations. The equation below gives an approximation of the package power dissipation: PIC(DISS) ≅ VRMS IRMS COS θ where: VRMS = RMS voltage from VDD to VOUT when sourcing current and RMS voltage from VOUT to VSS when sinking current. IRMS = RMS current flowing out of or into the op amp and the load. θ = phase difference between the voltage and the current. For resistive loads, COS θ = 1. For example, the circuit in Figure 1 has a package power dissipation of 196mW: _______________________________________________________________________________________ High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 MAX4230–MAX4234 RF 3.6V CIN RIN LEFT AUDIO INPUT R COUT HEADPHONE JACK TO 32Ω STEREO HEADSET C VIN = 2Vp-p VBIAS R MAX4230 MAX4230 MAX4231 CIN 32Ω RIN RIGHT AUDIO INPUT COUT RF Figure 1. MAX4230/MAX4231 Used in Single-Supply Operation Circuit Example ( ) RMS ≅ VDD − VDC + VPEAK = 3.6V − 1.8V + 2 1.0V = 2.507VRMS 2 I 1.8V 1.0V / 32Ω IRMS ≅ IDC + PEAK = + 32Ω 2 2 = 78.4mARMS where: VDC = the DC component of the output voltage. IDC = the DC component of the output current. VPEAK = the highest positive excursion of the AC component of the output voltage. IPEAK = the highest positive excursion of the AC component of the output current. Therefore: PIC(DISS) = VRMS IRMS COS θ = 196mW Adding a coupling capacitor improves the package power dissipation because there is no DC current to the load, as shown in Figure 2: Figure 2. Circuit Example: Adding a Coupling Capacitor Greatly Reduces Power Dissipation of its Package VRMS ≅ = VPEAK 2 1.0V 2 = 0.707VRMS I IRMS ≅ IDC + PEAK 2 = 22.1mARMS = 0A + 1.0V / 32Ω 2 Therefore: PIC(DISS) = VRMS IRMS COS θ = 15.6mW If the configuration in Figure 1 were used with all four of the MAX4234 amplifiers, the absolute maximum powerdissipation rating of this package would be exceeded (see the Absolute Maximum Ratings section). 60mW Single-Supply Stereo Headphone Driver Two MAX4230/MAX4231s can be used as a single-supply, stereo headphone driver. The circuit shown in Figure 2 can deliver 60mW per channel with 1% distortion from a single +5V supply. The input capacitor (CIN), in conjunction with RIN forms a highpass filter that removes the DC bias from the incoming signal. The -3dB point of the highpass filter is given by: f −3dB = 1 2πRINCIN _______________________________________________________________________________________ 9 MAX4230–MAX4234 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 C1 0.1µF R1 16kΩ R2 82kΩ 0.5Vp-p 1/2 +3V +3V 2 R5 51kΩ C2 0.1µF VCC = +3.0V RL = 100kΩ 3 IN (1V/div) MAX4232 1 8 4 32Ω fs = 100Hz R4 10kΩ R3 10kΩ OUT (1V/div) 6 R6 51kΩ 7 5 1/2 MAX4232 Figure 3. Dual MAX4230/MAX4231 Bridge Amplifier for 200mW at 3V Choose gain setting resistors RIN and RF according to the amount of desired gain, keeping in mind the maximum output amplitude. The output coupling capacitor, COUT, blocks the DC component of the amplifier output, preventing DC current flowing to the load. The output capacitor and the load impedance form a highpass filer with the -3dB point determined by: f −3dB = 1 2πRLCOUT For a 32Ω load, a 100µF aluminum electrolytic capacitor gives a low-frequency pole at 50Hz. Bridge Amplifier The circuit shown in Figure 3 uses a dual MAX4230 to implement a 3V, 200mW amplifier suitable for use in size-constrained applications. This configuration eliminates the need for the large coupling capacitor required by the single op amp speaker driver when single-supply operation is necessary. Voltage gain is set to +10V/V; however, it can be changed by adjusting the 82kΩ resistor value. Rail-to-Rail Input Stage The MAX4230–MAX4234 CMOS operational amplifiers have parallel-connected N- and P-channel differential input stages that combine to accept a common-mode range extending to both supply rails. The N-channel stage is active for common-mode input voltages typically greater than (V SS + 1.2V), and the P-channel stage is active for common-mode input voltages typically less than (VDD - 1.2V). 10 TIME (5µs/div) Figure 4. Rail-to-Rail Input/Output Range Rail-to-Rail Output Stage The minimum output is within millivolts of ground for single-supply operation, where the load is referenced to ground (VSS). Figure 4 shows the input voltage range and the output voltage swing of a MAX4230 connected as a voltage follower. The maximum output voltage swing is load dependent; however, it is guaranteed to be within 500mV of the positive rail (VDD = +2.7V) even with maximum load (32Ω to ground). The MAX4230–MAX4234 incorporate a smart short-circuit protection feature. When VOUT is shorted to VDD or VSS, the device detects a fault condition and limits the output current, therefore protecting the device and the application circuit. If VOUT is shorted to any voltage other than VDD or VSS, the smart short-circuit protection is not activated. When the smart short circuit is not active, the output currents can exceed 200mA (see Typical Operating Characteristics.) Input Capacitance One consequence of the parallel-connected differential input stages for rail-to-rail operation is a relatively large input capacitance CIN (typically 5pF). This introduces a pole at frequency (2πR′CIN)-1, where R′ is the parallel combination of the gain-setting resistors for the inverting or noninverting amplifier configuration (Figure 5). If the pole frequency is less than or comparable to the unity-gain bandwidth (10MHz), the phase margin is reduced, and the amplifier exhibits degraded AC performance through either ringing in the step response or sustained oscillations. The pole frequency is 10MHz when R′ = 2kΩ. To maximize stability, R′ << 2kΩ is recommended. ______________________________________________________________________________________ High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 R VOUT MAX4230 R′ = R || Rf RfCf = RCIN CAPACITIVE LOAD (pF) 2000 Rf VIN MAX4230–MAX4234 2500 Cf INVERTING UNSTABLE 1500 STABLE 1000 500 VDD = +5.0V RL TO VDD/2 0 1 10 100 1000 10,000 100,000 RESISTIVE LOAD (Ω) NONINVERTING VIN Figure 6. Capacitive Load Stability VOUT MAX4230 Rf Cf R 20mV/div R′ = R || Rf RfCf = RCIN 20mV/div VDD = +3.0V, CL = 1500pF RL = 100kΩ, RISO = 0 Figure 5. Inverting and Noninverting Amplifier with Feedback Compensation To improve step response when R′ > 2kΩ, connect a small capacitor Cf between the inverting input and output. Choose Cf as follows: 1µs/div Figure 7. Small-Signal Transient Response with Excessive Capacitive Load Cf = 8(R / Rf) [pf] where Rf is the feedback resistor and R is the gain-setting resistor (Figure 5). Driving Capacitive Loads The MAX4230–MAX4234 have a high tolerance for capacitive loads. They are stable with capacitive loads up to 780pF. Figure 6 is a graph of the stable operating region for various capacitive loads vs. resistive loads. Figures 7 and 8 show the transient response with excessive capacitive loads (1500pF), with and without the addition of an isolation resistor in series with the output. Figure 9 shows a typical noninverting capacitive-load-driving circuit in the unity-gain configuration. The resistor improves the circuit’s phase margin by isolating the load capacitor from the op amp’s output. 20mV/div 20mV/div VDD = +3.0V, CL = 1500pF RL = 100kΩ, RISO = 39Ω 1µs/div Figure 8. Small-Signal Transient Response with Excessive Capacitive Load with Isolation Resistor ______________________________________________________________________________________ 11 MAX4230–MAX4234 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 SHDN 2V/div IDD 1mA/div RISO CL OUT 2V/div 100µs/div Figure 9. Capacitive-Load-Driving Circuit 1V/div Figure 11. Shutdown Enable/Disable Supply Current VDD 2V/div IDD 1mA/div 1V/div 4µs/div Figure 10. Shutdown Output Voltage Enable/Disable 40µs/div Figure 12. Power-Up/Down Supply Current Selector Guide Power-Up and Shutdown Modes The MAX4231/MAX4233 have a shutdown option. When the shutdown pin (SHDN) is pulled low, supply current drops to 0.5µA per amplifier (VDD = +2.7V), the amplifiers are disabled, and their outputs are driven to VSS. Since the outputs are actively driven to VSS in shutdown, any pullup resistor on the output causes a current drain from the supply. Pulling SHDN high enables the amplifier. In the dual MAX4233, the two amplifiers shut down independently. Figure 10 shows the MAX4231’s output voltage to a shutdown pulse. The MAX4231–MAX4234 typically settle within 5µs after power-up. Figures 11 and 12 show IDD to a shutdown plus and voltage power-up cycle. PART AMPS PER PACKAGE MAX4230 Single — MAX4231 Single Yes MAX4232 Dual — MAX4233 Dual Yes MAX4234 Quad — When exiting shutdown, there is a 6µs delay before the amplifier’s output becomes active (Figure 10). 12 ______________________________________________________________________________________ SHUTDOWN MODE High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 TOP VIEW IN+ 1 5 VDD IN- 3 6 VDD VSS 2 5 SHDN IN- 3 4 OUT 4 OUT SOT23/SC70 A1 A2 A3 OUTB INB- INB+ VDD C1 OUTA MAX4233 C2 INA- C3 8 VDD 7 OUT2 IN1+ 3 6 IN2- VSS 4 5 IN2+ MAX4232 SOT23/µMAX A4 10 VDD OUT1 1 IN1- 2 IN1+ 3 MAX4233 IN1- 2 IN2- IN1+ 3 VSS 4 7 IN2+ C4 SHDN1 5 6 SHDN2 UCSP 13 IN4- OUT2 4 µMAX 14 OUT4 8 VSS INA+ OUT1 1 9 VSS SHDNA 12 IN4+ MAX44234 11 VDD IN2+ 5 10 IN3+ IN2- 6 9 IN3- OUT2 7 8 OUT3 TSSOP/SO Ordering Information (continued) TEMP. RANGE PINPACKAGE TOP MARK MAX4232AKA-T* -40°C to +125°C 8 SOT23-8 — MAX4232AUA* -40°C to +125°C 8 µMAX — MAX4233AUB -40°C to +125°C 10 µMAX — MAX4233ABB-T* -40°C to +125°C 10 UCSP — MAX4234AUD* -40°C to +125°C 14 TSSOP — MAX4234ASD* -40°C to +125°C 14 SO — PART OUT1 1 SC70/SOT23 SHDNB B4 B1 MAX4231 IN1- 2 MAX4230 VSS 2 IN+ 1 Chip Information MAX4230 TRANSISTOR COUNT: 230 MAX4231 TRANSISTOR COUNT: 230 MAX4232 TRANSISTOR COUNT: 462 MAX4233 TRANSISTOR COUNT: 462 MAX4234 TRANSISTOR COUNT: 924 *Future product—contact factory for availablility. Power Supplies and Layout The MAX4230–MAX4234 can operate from a single +2.7V to +5.5V supply, or from dual ±1.35V to ±2.5V supplies. For single-supply operation, bypass the power supply with a 0.1µF ceramic capacitor. For dualsupply operation, bypass each supply to ground. Good layout improves performance by decreasing the amount of stray capacitance at the op amps’ inputs and outputs. Decrease stray capacitance by placing external components close to the op amps’ pins, minimizing trace and lead lengths. ______________________________________________________________________________________ 13 MAX4230–MAX4234 Pin Configurations MAX4230–MAX4234 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 SC70, 6L.EPS SC70, 5L.EPS Package Information 14 ______________________________________________________________________________________ High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 SOT5L.EPS 6LSOT.EPS ______________________________________________________________________________________ 15 MAX4230–MAX4234 Package Information (continued) MAX4230–MAX4234 High-Output-Drive, 10MHz, 10V/µs, Rail-to-Rail I/O Op Amps with Shutdown in SC70 8LUMAXD.EPS Package Information (continued) 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 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.