19-4433; Rev 3; 4/11 High-Voltage, Precision, Low-Power Op Amps The MAX9943/MAX9944 is a family of high-voltage amplifiers that offers precision, low drift, and low-power consumption. The MAX9943 (single) and MAX9944 (dual) op amps offer 2.4MHz of gain-bandwidth product with only 550μA of supply current per amplifier. The MAX9943/MAX9944 family has a wide power supply range operating from ±3V to ±19V dual supplies or a 6V to 38V single supply. The MAX9943/MAX9944 is ideal for sensor signal conditioning, high-performance industrial instrumentation and loop-powered systems (e.g., 4mA–20mA transmitters). The MAX9943 is offered in a space-saving 6-pin TDFN or 8-pin μMAX® package. The MAX9944 is offered in an 8-pin SO or an 8-pin TDFN package. These devices are specified over the -40°C to +125°C automotive temperature range. Features o Wide 6V to 38V Supply Range o Low 100µV (max) Input Offset Voltage o Low 0.4µV/°C Offset Drift o Unity Gain Stable with 1nF Load Capacitance o 2.4MHz Gain-Bandwidth Product o 550µA Supply Current o 20mA Output Current o Rail-to-Rail Output o Package Options 3mm x 5mm, 8-Pin µMAX or 3mm x 3mm, 6-Pin TDFN Packages (Single) 5mm x 6mm, 8-Pin SO or 3mm x 3mm, 8-Pin TDFN Packages (Dual) Ordering Information Applications PINPACKAGE TOP MARK 8 μMAX AACA PART TEMP RANGE Loop-Powered Systems MAX9943AUA+ -40°C to +125°C Industrial Instrumentation MAX9943ATT+ -40°C to +125°C 6 TDFN-EP* High-Voltage ATE MAX9944ASA+ -40°C to +125°C 8 SO High-Performance ADC/DAC Input/Output Amplifiers MAX9944ATA+ -40°C to +125°C 8 TDFN-EP* Sensor Interfaces μMAX is a registered trademark of Maxim Integrated Products, Inc. MAX9943 toc17 UNSTABLE CLOAD (pF) 10,000 1000 — BLN +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Package Detail Capacitive Load vs. Resistive Load 100,000 AUF TOP VIEW MAX9943 OUT 1 VEE IN+ *EP 6 VCC 2 5 N.C. 3 4 IN- STABLE 100 100 1000 10,000 100,000 RLOAD (Ω) TOP VIEW 6 TDFN-EP *EP = EXPOSED PAD. Pin Configurations appear at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX9943/MAX9944 General Description MAX9943/MAX9944 High-Voltage, Precision, Low-Power Op Amps ABSOLUTE MAXIMUM RATINGS Supply Voltage (VCC to VEE) ..................................-0.3V to +40V All Other Pins (Note 1) .....................(VEE - 0.3V) to (VCC + 0.3V) OUT Short-Circuit Current Duration 8-Pin μMAX (VCC - VEE ≤ 20V)...............................................3s 8-Pin μMAX (VCC - VEE > 20V) ................................Momentary 6-Pin TDFN (VCC - VEE ≤ 20V) .............................................60s 6-Pin TDFN (VCC - VEE > 20V)...............................................2s 8-Pin SO (VCC - VEE ≤ 20V) .................................................60s 8-Pin SO (VCC - VEE > 20V)...................................................2s 8-Pin TDFN (VCC - VEE ≤ 20V) .............................................60s 8-Pin TDFN (VCC - VEE > 20V)...............................................2s Continuous Input Current (Any Pins) ................................±20mA Thermal Limits (Note 2) Multiple Layer PCB Continuous Power Dissipation (TA = +70°C) 8-Pin μMAX (derate 4.8mW/°C above +70°C) ...........387.8mW 6-Pin TDFN-EP (derate 23.8mW/°C above +70°C) ..1904.8mW 8-Pin SO (derate 7.6mW/°C above +70°C)...................606.1W 8-Pin TDFN-EP (derate 24.4mW/°C above +70°C) ..1951.2mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Lead Temperature (soldering, 10s) .................................+300°C Soldering Temperature (reflow) .......................................+260°C Note 1: Operation is limited by thermal limits. 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. PACKAGE THERMAL CHARACTERISTICS (Note 2) 8 μMAX Junction-to-Ambient Thermal Resistance (θJA)......206.3°C/W Junction-to-Ambient Case Resistance (θJC) ...............42°C/W 6 TDFN-EP Junction-to-Ambient Thermal Resistance (θJA)...........42°C/W Junction-to-Ambient Case Resistance (θJC) .................9°C/W 8 SO Junction-to-Ambient Thermal Resistance (θJA).........132°C/W Junction-to-Ambient Case Resistance (θJC) ...............38°C/W 8 TDFN-EP Junction-to-Ambient Thermal Resistance (θJA)...........41°C/W Junction-to-Ambient Case Resistance (θJC) .................8°C/W Note 2: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (VCC = 15V, VEE = -15V, VCM = 0V, RL = 10kΩ to GND, VGND = 0V, TA = -40°C to +125°C. Typical values are at TA = +25°C, unless otherwise noted.) (Note 3) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS ±19 V 950 μA DC CHARACTERISTICS Operating Supply Voltage Range VSUPPLY Quiescent Supply Current per Amplifier ICC Power-Supply Rejection Ratio PSRR Input Offset Voltage Input Offset Voltage Drift Input Bias Current VOS IBIAS IOS Input Voltage Range VIN+ , VIN- 2 ±3 550 VS = ±3V to ±19V 105 TA = +25°C CMRR 130 20 TA = -40°C to +125°C dB 100 240 TCVOS Input Offset Current Common-Mode Rejection Ratio Guaranteed by PSRR test 0.4 VEE + 0.3V ≤ VCM ≤ VCC - 1.8V 4 VEE ≤ VCM ≤ VCC - 1.8V μV/°C 20 90 VEE ≤ VCM ≤ VCC - 1.8V 1 Guaranteed by CMRR test, TA = -40°C to +125°C VEE VEE + 0.3V ≤ VCM ≤ VCC - 1.8V 105 VEE ≤ VCM ≤ VCC - 1.8V 105 125 _______________________________________________________________________________________ μV nA 10 nA VCC 1.8 V dB High-Voltage, Precision, Low-Power Op Amps (VCC = 15V, VEE = -15V, VCM = 0V, RL = 10kΩ to GND, VGND = 0V, TA = -40°C to +125°C. Typical values are at TA = +25°C, unless otherwise noted.) (Note 3) PARAMETER Open-Loop Gain SYMBOL AVOL CONDITIONS MIN TYP -13.5V ≤ VO ≤ +13.5V, RL = 10kΩ, TA = +25°C 115 130 -13.5V ≤ VO ≤ +13.5V, RL = 10kΩ, TA = -40°C to +125°C 100 -12V ≤ VO ≤ +12V, RL = 600Ω, TA = +25°C 100 -12V ≤ VO ≤ +12V, RL = 600Ω, TA = -40°C to +85°C 90 RL = 600Ω TA = +25°C TA = -40°C to +85°C Output Voltage Swing dB 110 VCC 1.8 VCC - 2 VEE + 0.1 VEE + 1 VEE + 1.1 RL = 10kΩ TA = +25°C VOL RL = 600Ω TA = -40°C to +85°C Short-Circuit Current ISC UNITS VCC 0.2 RL = 10kΩ VOH MAX TA = +25°C 60 TA = -40°C to +125°C 100 V mA AC CHARACTERISTICS Gain Bandwidth Product GBWP 2.4 MHz Slew Rate SR -5V ≤ VOUT ≤ +5V 0.35 V/μs Input Voltage Noise Density en f = 1kHz 17.6 nV/√Hz TOTAL NOISE 0.1Hz ≤ f ≤ 10Hz Input Voltage Noise Input Current Noise Density Capacitive Loading In CLOAD 500 nVP-P f = 1kHz 0.18 pA/√Hz No sustained oscillation 1000 pF Note 3: All devices are 100% production tested at TA = +25°C. Temperature limits are guaranteed by design. _______________________________________________________________________________________ 3 MAX9943/MAX9944 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VCC = 15V, VEE = -15V, VCM = 0V, RL = 10kΩ to GND, VGND = 0V, TA = +25°C, unless otherwise noted.) INPUT VOLTAGE OFFSET DRIFT HISTOGRAM 10 650 SUPPLY CURRENT (µA) 15 700 MAX9943 toc02 60 FREQUENCY (%) 20 SUPPLY CURRENT vs. SUPPLY VOLTAGE 70 MAX9943 toc01 25 50 40 30 20 5 6 10 14 18 22 500 MAX9943 toc05 25 OFFSET VOLTAGE (µV) 600 400 20 15 10 5 0 300 -50 -25 0 25 50 75 100 6 125 10 14 18 22 26 30 34 38 SUPPLY VOLTAGE (V) TEMPERATURE (°C) OFFSET VOLTAGE vs. COMMON-MODE VOLTAGE OFFSET VOLTAGE vs. TEMPERATURE 80 OFFSET VOLTAGE (µV) 25 20 15 10 5 MAX9943 toc07 100 MAX9943 toc06 30 60 40 20 0 -20 0 -40 -14 -10 -6 -2 2 6 COMMON-MODE VOLTAGE (V) 10 14 -50 -25 26 SUPPLY VOLTAGE (V) 30 MAX9943 toc04 700 SUPPLY CURRENT (µA) 450 OFFSET VOLTAGE vs. SUPPLY VOLTAGE SUPPLY CURRENT vs. TEMPERATURE OFFSET VOLTAGE (µV) 500 300 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 -0.25 -0.15 -0.05 0.05 0.15 0.25 VOS DRIFT (µV/°C) 800 4 550 350 0 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 OFFSET VOLTAGE (µV) 600 400 10 0 MAX9943 toc03 OFFSET VOLTAGE HISTOGRAM FREQUENCY (%) MAX9943/MAX9944 High-Voltage, Precision, Low-Power Op Amps 0 25 50 75 100 125 TEMPERATURE (°C) _______________________________________________________________________________________ 30 34 38 High-Voltage, Precision, Low-Power Op Amps INPUT BIAS CURRENT vs. SUPPLY VOLTAGE INPUT BIAS CURRENT vs. COMMON-MODE VOLTAGE 2.0 1.5 1.0 0.5 2.0 1.5 1.0 0.5 0 0 -10 -6 -2 2 6 10 6 14 10 14 22 26 30 34 SUPPLY VOLTAGE (V) COMMON-MODE REJECTION RATIO vs. FREQUENCY POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 160 MAX9943 toc10 140 130 140 120 110 100 PSRR (dB) 120 100 60 80 40 70 20 0.1 1 10 100 0 0.001 0.01 1000 10,000 1 10 100 1000 10,000 VOL vs. OUTPUT CURRENT VOH vs. OUTPUT CURRENT OUTPUT VOLTAGE (V) TA = -40°C TA = +25°C 14 TA = +85°C TA = +125°C MAX9943 toc13 -12 MAX9943 toc12 16 13 0.1 FREQUENCY (kHz) FREQUENCY (kHz) 15 38 80 90 60 0.001 0.01 OUTPUT VOLTAGE (V) 18 COMMON-MODE VOLTAGE (V) MAX9943 toc11 -14 CMRR (dB) MAX9943 toc09 2.5 INPUT BIAS CURRENT (nA) 2.5 INPUT BIAS CURRENT (nA) 3.0 MAX9943 toc08 3.0 -13 TA = +85°C -14 TA = -40°C -15 12 TA = +125°C TA = +25°C -16 0 5 10 15 20 OUTPUT CURRENT (mA) 25 30 0 5 10 15 20 25 30 OUTPUT CURRENT (mA) _______________________________________________________________________________________ 5 MAX9943/MAX9944 Typical Operating Characteristics (continued) (VCC = 15V, VEE = -15V, VCM = 0V, RL = 10kΩ to GND, VGND = 0V, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (VCC = 15V, VEE = -15V, VCM = 0V, RL = 10kΩ to GND, VGND = 0V, TA = +25°C, unless otherwise noted.) INPUT VOLTAGE NOISE vs. FREQUENCY OUTPUT IMPEDANCE vs. FREQUENCY 10 1 0.1 MAX9943 toc15 MAX9943 toc14 100 100 90 INPUT VOLTAGE NOISE (nV/√Hz) OUTPUT IMPEDANCE (Ω) 1000 80 70 60 50 40 30 20 10 0 0.01 0.1 1 10 100 1000 1 10,000 10 100 1000 10,000 100,000 FREQUENCY (Hz) FREQUENCY (kHz) OPEN-LOOP GAIN vs. FREQUENCY CAPACITIVE LOAD vs. RESISTIVE LOAD 120 100,000 MAX9943 toc17 MAX9943 toc16 140 100 UNSTABLE 10,000 80 CLOAD (pF) OPEN-LOOP GAIN (dB) MAX9943/MAX9944 High-Voltage, Precision, Low-Power Op Amps 60 40 1000 STABLE 20 0 -20 10 0.001 0.1 0.00001 1000 10,000 1 0.0001 100 0.01 FREQUENCY (kHz) 100 100 1000 10,000 100,000 RLOAD (Ω) LARGE SIGNAL-STEP RESPONSE SMALL SIGNAL-STEP RESPONSE MAX9943 toc19 MAX9943 toc18 1V/div 20mV/div OUT OUT 1μs/div 6 10μs/div _______________________________________________________________________________________ High-Voltage, Precision, Low-Power Op Amps MAX9943 6 TDFN-EP MAX9943 8 µMAX MAX9944 8 SO/TDFN-EP NAME FUNCTION 1 6 — OUT — — 1 OUTA Output — — 7 OUTB 2 4 4 VEE Negative Power Supply. Bypass with a 0.1μF capacitor to ground. 3 3 — IN+ Positive Input — — 3 INA+ — — 5 INB+ Positive Input B 4 2 — IN- Negative Input — — 2 INA- — — 6 INB- Negative Input B 5 1, 5, 8 — N.C. No Connection 6 7 8 VCC Positive Power Supply. Bypass with a 0.1μF capacitor to ground. — — — EP Output A Output B Positive Input A Negative Input A Exposed Pad (TDFN Only). Connect to a large VEE plane to maximize thermal performance. Not intended as an electrical connection point. Detailed Description The MAX9943/MAX9944 are single/dual operational amplifiers designed for industrial applications. They operate from 6V to 38V supply range while maintaining excellent performance. These devices utilize a threestage architecture optimized for low offset voltage and low input noise with only 550μA supply current. The devices are unity gain stable with a 1nF capacitive load. These well-matched devices guarantee the high open-loop gain, CMRR, PSRR, and low voltage offset. The MAX9943/MAX9944 provide a wide input/output voltage range. The input terminals of the MAX9943/ MAX9944 are protected from excessive differential voltage with back-to-back diodes. The input signal current is also limited by an internal series resistor. With a 40V differential voltage, the input current is limited to 20mA. The output can swing to the negative rail while delivering 20mA of current, which is ideal for loop-powered system applications. The specifications and operation of the MAX9943/MAX9944 family is guaranteed over the -40°C to +125°C temperature range. Application Information Bias Current vs. Input Common Mode The MAX9943/MAX9944 use an internal bias current cancellation circuit to achieve very low bias current over a wide input common-mode range. For such a circuit to function properly, the input common mode must be at least 300mV away from the negative supply VEE. The input common mode can reach the negative supply VEE. However, in the region between VEE and VEE + 0.3V, there is an increase in bias current for both inputs. Capacitive Load Stability Driving large capacitive loads can cause instability in many op amps. The MAX9943/MAX9944 are stable with capacitive loads up to 1nF. The Capacitive Load vs. Resistive Load graph in the Typical Operating Characteristics gives the stable operation region for capacitive versus resistive loads. Stability with higher capacitive loads can be improved by adding an isolation resistor in series with the op-amp output, as shown in Figure 1. This resistor improves the circuit’s phase margin by isolating the load capacitor from the amplifier’s output. _______________________________________________________________________________________ 7 MAX9943/MAX9944 Pin Description MAX9943/MAX9944 High-Voltage, Precision, Low-Power Op Amps Power Supplies and Layout The MAX9943/MAX9944 can operate with dual supplies from ±3V to ±19V or with a single supply from +6V to +38V with respect to ground. When used with dual supplies, bypass both VCC and VEE with their own 0.1μF capacitor to ground. When used with a single supply, bypass VCC with a 0.1μF capacitor to ground. Careful layout technique helps optimize performance by decreasing the amount of stray capacitance at the op amp’s inputs and outputs. To decrease stray capacitance, minimize trace lengths by placing external components close to the op amp’s pins. RISO OUTPUT MAX9943 CL INPUT Figure 1. Capacitive Load Driving Circuit Output Current Capability The MAX9943/MAX9944 are capable of driving heavy loads such as the ones that can be found in loop-powered systems for remote sensors. The information is transmitted through ±20mA or 4mA–20mA current output across long lines that are terminated with low resistance loads (e.g., 600Ω). The Typical Application Circuit shows the MAX9944 used as a voltage-to-current converter with a current-sense amplifier in the feedback loop. Because of the high output current capability of the MAX9944, the device can be used to directly drive the current-loop. Figure 2. Input Protection Circuit The specifications and operation of the MAX9943/ MAX9944 family is guaranteed over the -40°C to +125°C temperature range, However, when used in applications with ±15V supply voltage (see Figure 3), the capability of driving more than ±20mA of current is limited to the -40°C to +85°C temperature range. Use a lower supply voltage if this current must be delivered at a higher temperature range. During normal op-amp operation, the inverting and noninverting inputs of the MAX9943/MAX9944 are at essentially the same voltage. However, either due to fast input voltage transients or due to other fault conditions, these pins can be forced to be at two different voltages. Input Common Mode and Output Swing The MAX9943/MAX9944 input common-mode range can swing to the negative rail VEE. The output voltage can swing to both the positive VCC and the negative VEE rails if the output stage is not heavily loaded. These two features are very important for applications where the MAX9943/ MAX9944 are used with a single-supply (VEE connected to ground). One of the applications that can benefit from these features is when the single-supply op amp is driving an ADC. 8 1.5kΩ 1.5kΩ Input Differential Voltage Protection Internal back-to-back diodes and series resistors protect the inputs from an excessive differential voltage (see Figure 2). Therefore, IN+ and IN- can be any voltage within the range shown in the absolute maximum rating. Note the protection time is still dependent on the package thermal limits. Chip Information PROCESS: BiCMOS _______________________________________________________________________________________ High-Voltage, Precision, Low-Power Op Amps MAX9943/MAX9944 +15V -15V VREF RSENSE DAC MAX9944 RLOAD -15V Figure 3. Typical ±20mA Current-Source in Loop-Powered Systems _______________________________________________________________________________________ 9 High-Voltage, Precision, Low-Power Op Amps MAX9943/MAX9944 Pin Configurations TOP VIEW MAX9944 MAX9943 + + N.C. 1 8 N.C. IN- 2 7 IN+ 3 VEE 4 OUTA 1 8 VCC VCC INA- 2 7 OUTB 6 OUT INA+ 3 6 INB- 5 N.C. VEE 4 5 INB+ 1 8 VCC INA- 2 7 OUTB INA+ 6 INB- 5 INB+ 8 μMAX 8 SO TOP VIEW MAX9944 MAX9943 + OUT 1 VEE 2 IN+ *EP 3 6 VCC 5 N.C. 4 TOP VIEW 6 TDFN IN- OUTA 3 VEE 4 *EP TOP VIEW 8 TDFN NOT TO SCALE. *EP = EXPOSED PAD. 10 ______________________________________________________________________________________ High-Voltage, Precision, Low-Power Op Amps PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 μMAX U8+1 21-0036 90-0092 6 TDFN-EP T633+2 21-0137 90-0058 8 SO S8+4 21-0041 90-0096 8 TDFN-EP T833+2 21-0137 90-0059 α α ______________________________________________________________________________________ 11 MAX9943/MAX9944 Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. MAX9943/MAX9944 High-Voltage, Precision, Low-Power Op Amps Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. 12 ______________________________________________________________________________________ High-Voltage, Precision, Low-Power Op Amps COMMON DIMENSIONS PACKAGE VARIATIONS MIN. MAX. PKG. CODE N D2 E2 e JEDEC SPEC b A 0.70 0.80 T633-2 6 1.50±0.10 2.30±0.10 0.95 BSC MO229 / WEEA 0.40±0.05 1.90 REF D 2.90 3.10 T833-2 8 1.50±0.10 2.30±0.10 0.65 BSC MO229 / WEEC 0.30±0.05 1.95 REF E 2.90 3.10 T833-3 8 1.50±0.10 2.30±0.10 0.65 BSC MO229 / WEEC 0.30±0.05 1.95 REF 2.00 REF SYMBOL [(N/2)-1] x e A1 0.00 0.05 T1033-1 10 1.50±0.10 2.30±0.10 0.50 BSC MO229 / WEED-3 0.25±0.05 L 0.20 0.40 T1033MK-1 10 1.50±0.10 2.30±0.10 0.50 BSC MO229 / WEED-3 0.25±0.05 2.00 REF 10 1.50±0.10 2.30±0.10 0.50 BSC MO229 / WEED-3 0.25±0.05 2.00 REF k 0.25 MIN. T1033-2 A2 0.20 REF. T1433-1 14 1.70±0.10 2.30±0.10 0.40 BSC ---- 0.20±0.05 2.40 REF T1433-2 14 1.70±0.10 2.30±0.10 0.40 BSC ---- 0.20±0.05 2.40 REF T1433-3F 14 1.70±0.10 2.30±0.10 0.40 BSC ---- 0.20±0.05 2.40 REF ______________________________________________________________________________________ 13 MAX9943/MAX9944 Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. MAX9943/MAX9944 High-Voltage, Precision, Low-Power Op Amps Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. 14 ______________________________________________________________________________________ High-Voltage, Precision, Low-Power Op Amps REVISION NUMBER REVISION DATE DESCRIPTION 0 3/09 Initial release 1 4/09 Removed future product reference for the MAX9944, updated EC table 2 6/09 Corrected TOC 13 and added rail-to-rail output feature 3 4/11 Updated Pin Description section PAGES CHANGED — 1, 2 1, 3, 5, 8 7 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, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 © 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX9943/MAX9944 Revision History