19-4814; Rev 1; 1/11 250mA to 1.5A, Adjustable Current-Limit Switches Features The MAX14523A/MAX14523AL/MAX14523B/MAX14523C programmable current-limit switches feature internal current limiting to prevent damage to host devices due to faulty load conditions. These current-limit switches feature a low 70mΩ on-resistance and operate from a +1.7V to +5.5V input voltage range. The current limit is adjustable from 250mA to 1.5A, making these devices ideal for SDIO (secure digital input/output) and other load-switching applications. Each device in the family handles an overcurrent event differently depending on the option selected. The MAX14523A/MAX14523AL go into an autoretry mode, the MAX14523B latches off the switch, and the MAX14523C features a continuous current-limit mode. Additional safety features include thermal shutdown to prevent overheating and reverse-current blocking to prevent current from being driven back into the source. The MAX14523A/MAX14523AL/MAX14523B/MAX14523C are available in a tiny 8-pin, 3mm x 3mm, TDFN package and operate over the -40°C to +125°C automotive temperature range. ♦ Accurate (±10%) Overload Current Limit ♦ Adjustable Current-Limit Threshold ♦ Low-Dropout Voltage (70mV at 1A Load Current) ♦ Short-Circuit Protection ♦ Thermal-Shutdown Protection ♦ Reverse-Current Protection ♦ 170µA (typ) Supply Current ♦ Shutdown Reverse Current, 0.6µA (max) ♦ +1.7V to +5.5V Supply Voltage Range ♦ Tiny 8-Pin, 3mm x 3mm, TDFN Package Typical Operating Circuit BIAS VOLTAGE IN POWER SUPPLY OUT 1μF LOAD 1μF Applications CHARGE PUMP SDIO Ports RSETI USB Ports μP CURRENT REFERENCE VPULLUP CONTROL LOGIC Notebook VGA Ports 10kΩ GPS FLAG Cell Phones N.C. ON(ON)* MP3 Players UTCA/ATCA Platforms GND MAX14523A MAX14523AL MAX14523B MAX14523C *ON FOR THE MAX14523AL ONLY. Pin Configuration appears at end of data sheet. Ordering Information/Selector Guide PART PIN-PACKAGE TOP MARK ON POLARTIY OVERCURRENT RESPONSE MAX14523AATA+ 8 TDFN-EP* BLO Active-High Autoretry MAX14523ALATA+** 8 TDFN-EP* BLP Active-Low Autoretry MAX14523BATA+ 8 TDFN-EP* BLQ Active-High Latch-Off MAX14523BATA/V+T 8 TDFN-EP* BLQ Active-High Latch-Off MAX14523CATA+ 8 TDFN-EP* BLS Active-High Continuous Note: All devices are specified over the -40°C to +125°C operating temperature range. +Denotes a lead(Pb)-free package/RoHs-compliant package. /V denotes an automotive qualified part. *EP = Exposed pad. **Future product—contact factory for availability. ________________________________________________________________ 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 MAX14523A/MAX14523AL/MAX14523B/MAX14523C General Description MAX14523A/MAX14523AL/MAX14523B/MAX14523C 250mA to 1.5A, Adjustable Current-Limit Switches ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) IN, ON, ON, FLAG, OUT, and SETI to GND .............-0.3V to +6V Current into Any Pin (Except IN, OUT)................................20mA Out Short Circuit to GND...................................Internally Limited Continuous Power Dissipation (TA = +70°C) for multilayer board: TDFN (derate 24.4mW/°C above +70°C)...................1952mW 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 Soldering Temperature (reflow) .......................................+260°C PACKAGE THERMAL CHARACTERISTICS (Note 1) TDFN Junction-to-Ambient Thermal Resistance (θJA) ...........41°C/W Junction-to-Case Thermal Resistance (θJC) ..................8°C/W Note 1: 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. 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. ELECTRICAL CHARACTERISTICS (VIN = +1.7V to +5.5V, RSETI = 94.2kΩ, CIN = COUT = 1µF, and TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at VIN = +3.3V, TA = +25°C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 5.5 V SUPPLY OPERATION Operating Voltage VIN Quiescent Current IQ 1.7 I OUT = 0A, switch on, VIN = 3.3V 170 300 μA 10 20 μA Latchoff Current ILATCH VIN = 3.3V, I OUT = 0A , after an overcurrent fault (MAX14523B) Shutdown Forward Current I SHDN VON = 0V, VON = VIN, VIN = 5.5V, VOUT = 0V 0.5 7 μA Shutdown Reverse Current IRSHDN VON = 0V, VON = VIN, VIN = 1.7V, VOUT = 5.5V (current into OUT) 0.01 0.6 μA m INTERNAL FET Switch-On Resistance Forward-Current Limit R ON ILIM VIN = 3.3V, I OUT lower than ILIM 70 130 RSETI = 91.78k, VIN - VOUT = 1V 1350 1500 1650 RSETI = 563.12k, VIN - VOUT = 1V 225 250 275 127.2 141.4 155.5 kV 2 μA 140 mV (RSETI +2.48k) × ILIM Product ILIM = 250mA to 1500mA, VIN - VOUT = 1V Reverse Blocking Current VOUT > VIN + 140mV, after reverse-currentlimit shutdown Reverse Blocking Threshold VOUT - VIN VOUT - VIN = 300mV, OUT falling until switch turns on FLAG Assertion Drop Voltage Threshold VFA Increase (VIN - VOUT) drop until FLAG asserts, I OUT limiting, VIN = 3.3V 40 95 350 mA mV ON, ON INPUT ON, ON Input Leakage ILEAK ON, ON Input Logic-High Voltage VIH ON, ON Input Logic-Low Voltage VIL 2 VON, VON = VIN or VGND -1 +1 1.6 _______________________________________________________________________________________ μA V 0.4 V 250mA to 1.5A, Adjustable Current-Limit Switches (VIN = +1.7V to +5.5V, RSETI = 94.2kΩ, CIN = COUT = 1µF, and TA = TJ = -40°C to +125°C, unless otherwise noted. Typical values are at VIN = +3.3V, TA = +25°C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS FLAG OUTPUT FLAG Output Logic-Low Voltage ISINK = 1mA FLAG Output Leakage Current VIN = VFLAG = 5.5V, FLAG deasserted 0.4 V 1 μA DYNAMIC Turn-On Time t SS Time from ENABLE signal to V OUT = 90% of VIN = 3.3V, Figure 1 1 ms Turn-Off Time t OFF Time from DISABLE signal to VOUT = 10% of VIN = 3.3V, RL = 20, Figure 1 250 μs Current-Limit Reaction Time tLIM VIN = 3.3V, RSETI = 91.78k to 563.12k, output high and then short-circuit applied 3 μs Blanking Time tBLANK (Note 3) 10 Retry Time tRETRY MAX14523A/MAX14523AL (Note 3) 14.5 320 25 ms 875 ms THERMAL PROTECTION Thermal Shutdown Low-to-high Thermal Shutdown Hysteresis +170 °C 15 °C Note 2: All devices are 100% tested at 125°C. Electrical limits across the full temperature range are guaranteed by design and correlation. t Note 3: Blanking time and retry time are generated by the same oscillator. Therefore, the ratio of RETRY is a constant value of 32. t BLANK See Figures 2 and 3. ON(ON)* tSS 90% VIN VOUT tOFF 10% VIN *( ) THE POLARITY OF THE SIGNAL IS REVERSED FOR THE MAX14523AL ONLY. Figure 1. Timing Diagram for Measuring Turn-On Time (tSS) and Turn-Off Time (tOFF) _______________________________________________________________________________________ 3 MAX14523A/MAX14523AL/MAX14523B/MAX14523C ELECTRICAL CHARACTERISTICS (continued) MAX14523A/MAX14523AL/MAX14523B/MAX14523C 250mA to 1.5A, Adjustable Current-Limit Switches tBLANK tRETRY tBLANK tRETRY tBLANK tBLANK OUT CURRENT LIMIT THE DEVICE GOES TO THERMAL-SHUTDOWN MODE LOAD CURRENT FLAG Figure 2. Autoretry Fault Diagram tBLANK tBLANK OUT CURRENT LIMIT LOAD CURRENT THE DEVICE GOES TO THERMAL-SHUTDOWN MODE FLAG Figure 3. Latchoff Fault Diagram 4 _______________________________________________________________________________________ 250mA to 1.5A, Adjustable Current-Limit Switches NORMALIZED CURRENT LIMIT vs. TEMPERATURE 1.50 1.45 1.40 0.95 2.65 3.60 4.55 5.50 250 200 150 100 -40 -7 26 59 92 125 1.70 2.65 3.60 4.55 TEMPERATURE (°C) SUPPLY VOLTAGE (V) QUIESCENT SUPPLY CURRENT vs. TEMPERATURE SHUTDOWN SUPPLY CURRENT vs. TEMPERATURE SHUTDOWN FORWARD CURRENT vs. TEMPERATURE 200 150 VIN = +3.3V VON = 0V 9 8 7 6 5 VIN = +5V 4 3 VIN = +3.3V 2 1 100 26 59 TEMPERATURE (°C) 92 125 VON = 0V, VOUT = 0V 9 8 7 6 VIN = +5.5V 5 4 3 VIN = +1.7V 2 1 0 -7 10 SHUTDOWN FORWARD CURRENT (μA) VIN = +5V QUIESCENT SUPPLY CURRENT (μA) MAX14523A toc04 250 10 5.50 MAX14523A toc06 SUPPLY VOLTAGE (V) 300 -40 MAX14523A toc03 MAX14523A toc02 1.00 300 0.90 1.70 QUIESCENT SUPPLY CURRENT (μA) 1.05 MAX14523A toc05 CURRENT LIMIT (A) 1.55 1.10 NORMALIZED CURRENT LIMIT MAX14523A toc01 1.60 QUIESCENT SUPPLY CURRENT vs. SUPPLY VOLTAGE QUIESCENT SUPPLY CURRENT (μA) CURRENT LIMIT vs. SUPPLY VOLTAGE 0 -40 -7 26 59 TEMPERATURE (°C) 92 125 -40 -7 26 59 92 125 TEMPERATURE (°C) _______________________________________________________________________________________ 5 MAX14523A/MAX14523AL/MAX14523B/MAX14523C Typical Operating Characteristics (VIN = +3.3V, CIN = 1µF, COUT = 1µF, RSETI = 94.2kΩ, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (VIN = +3.3V, CIN = 1µF, COUT = 1µF, RSETI = 94.2kΩ, TA = +25°C, unless otherwise noted.) SHUTDOWN REVERSE CURRENT vs. TEMPERATURE 6 5 4 3 25 2 VIN = +5.5V 20 15 10 1.15 5 -7 26 59 92 -40 125 1.00 0.95 0.90 -7 26 59 92 1.70 125 3.60 4.55 NORMALIZED ON-RESISTANCE vs. SUPPLY TEMPERATURE SWITCH TURN-ON TIME vs. SUPPLY TEMPERATURE SWITCH TURN-OFF TIME vs. SUPPLY TEMPERATURE 1.3 1.2 1.1 1.0 0.9 0.8 0.7 1.5 1.4 RLOAD = 20Ω VIN = +5.0V 1.3 1.2 1.1 1.0 0.9 VIN = +3.3V 0.8 0.7 1000 900 SWITCH TURN-OFF TIME (μs) MAX14523A toc10 1.4 700 600 500 300 200 0.6 100 0.5 0 26 59 92 125 -40 -7 26 59 TEMPERATURE (°C) 92 125 VIN = +5.0V 400 0.5 TEMPERATURE (°C) RLOAD = 20Ω 800 0.6 -7 5.50 MAX14523A toc12 VOLTAGE (V) MAX14523A toc11 TEMPERATURE (°C) 1.5 -40 2.65 TEMPERATURE (°C) SWITCH TURN-ON TIME (ms) -40 1.05 0.80 0 0 1.10 0.85 VIN = +3.3V 1 6 1.20 MAX14523A toc09 MAX14523B NORMALIZED ON-RESISTANCE 7 MAX14523A toc08 8 30 LATCHOFF CURRENT (μA) VON = 0V, VIN = +1.7V, VOUT = +5.5V 9 NORMALIZED ON-RESISTANCE vs. SUPPLY VOLTAGE LATCHOFF CURRENT vs. TEMPERATURE MAX14523A toc07 SHUTDOWN REVERSE CURRENT (μA) 10 NORMALIZED ON-RESISTANCE MAX14523A/MAX14523AL/MAX14523B/MAX14523C 250mA to 1.5A, Adjustable Current-Limit Switches VIN = +3.3V -40 -7 26 59 TEMPERATURE (°C) _______________________________________________________________________________________ 92 125 250mA to 1.5A, Adjustable Current-Limit Switches CURRENT LIMIT RESPONSE FLAG RESPONSE (OVERLOAD CONDITION) CURRENT LIMIT RESPONSE MAX14523A toc13 MAX14523A toc15 MAX14523A toc14 SUDDEN SHORT APPLIED AT OUTPUT RLOAD = 16.5Ω TO SUDDEN SHORT APPLIED AT OUTPUT RLOAD = 16.5Ω TO SUDDEN SHORT APPLIED AT OUTPUT VOUT 2V/div IOUT 10A/div 2μs/div VOUT 2V/div VFLAG 2V/div IOUT 1A/div IOUT 1A/div 20ms/div 20ms/div Pin Description PIN MAX14523AL MAX14523A MAX14523B MAX14523C NAME 1, 6 1, 6 N.C. No Connection. Not internally connected. Connect N.C. to GND or leave unconnected. FLAG Open-Drain, Overload Indicator Output. FLAG goes low when the overload fault duration exceeds the blanking time, reverse current is detected, thermal shutdown mode is active, or SETI is connected to ground. 2 2 FUNCTION 3 3 SETI Overload-Current Limit Adjust. Connect a resistor from SETI to GND to program the overcurrent limit. If SETI is connected to GND the switch turns off and FLAG is asserted. If SETI is unconnected the current limit is at 0mA. Do not connect any capacitance larger than 20pF to SETI. 4 4 OUT Switch Output. Bypass OUT with a 1μF capacitor to GND. 5 5 IN Power Input. Bypass IN with a 1μF ceramic capacitor to GND. Use higher capacitance if necessary to prevent large load transients from pulling down the supply voltage. 7 ON Active-Low, Switch-ON Input. Drive ON low to turn on the switch. 7 ON 8 8 GND — — EP Active-High, Switch-ON Input. Drive ON high to turn on the switch. Ground Exposed Pad. Internally connected to GND. For enhanced thermal dissipation, connect EP to a large copper ground plane. Do not use EP as the sole ground connection. _______________________________________________________________________________________ 7 MAX14523A/MAX14523AL/MAX14523B/MAX14523C Typical Operating Characteristics (continued) (VIN = +3.3V, CIN = 1µF, COUT = 1µF, RSETI = 94.2kΩ, TA = +25°C, unless otherwise noted.) MAX14523A/MAX14523AL/MAX14523B/MAX14523C 250mA to 1.5A, Adjustable Current-Limit Switches Functional Diagram REVERSECURRENT PROTECTION IN OUT THERMAL SHUTDOWN BUFFER CONTROL LOGIC FLAG TIMING CIRCUITRY N.C. MAX14523A MAX14523AL MAX14523B MAX14523C BANDGAP REFERENCE CURRENT LIMIT BUFFER ON/(ON)* SETI GND *( ) FOR THE MAX14523AL ONLY Detailed Description The MAX14523A/MAX14523AL/MAX14523B/MAX14523C programmable current-limit switches operate from +1.7V to +5.5V and provide internal current limiting adjustable from 250mA to 1.5A. These devices feature a fixed blanking time, and a FLAG output that notifies the processor when a fault condition is present. Programmable Current Limit/Threshold A resistor from SETI to GND sets the current limit/threshold for the switch (see the Setting the Current Limit/Threshold section). If the output current is limited at the current threshold value for a time equal to or longer than tBLANK, the output flag asserts and the MAX14523A/MAX14523AL enter the autoretry mode, the MAX14523B latches off the switch, and the MAX14523C enters the continuous current-limit mode. 8 Autoretry (MAX14523A/MAX14523AL) When the forward current reaches the current threshold, the tBLANK timer begins counting (Figure 2). FLAG asserts if the overcurrent condition is present for tBLANK or longer. The timer resets if the overcurrent condition disappears before the blanking time (tBLANK) has elapsed. A retry time delay (tRETRY) starts immediately after the blanking time has elapsed. During that time, the switch latches off. At the end of tRETRY, the switch turns on again. If the fault still exists, the cycle repeats. If the fault has been removed, the switch stays on. During this cycle, FLAG stays low. In autoretry, if the die temperature exceeds +170°C (typ) due to self heating, the MAX14523A/MAX14523AL go into thermal shutdown until the die temperature drops by approximately 15°C (see the Thermal Shutdown section.) _______________________________________________________________________________________ 250mA to 1.5A, Adjustable Current-Limit Switches ILOAD = ILIM [(tBLANK )/(tBLANK + tRETRY)] With a typical tBLANK = 17.5ms and typical tRETRY = 560ms, the duty cycle is 3%, resulting in a 97% power savings over the switch being on the entire time. Latchoff (MAX14523B) When the forward current reaches the current threshold, the tBLANK timer begins counting (Figure 3). FLAG asserts if an overcurrent condition is present for greater than tBLANK time. The timer resets if the overcurrent condition disappears before t BLANK has elapsed. The switch turns off if the overcurrent condition continues beyond the blanking time. Reset the switch by either toggling the control logic (ON or ON) or cycling the input voltage. If the die temperature exceeds +170°C (typ) due to self heating, the MAX14523B goes into thermal shutdown until the die temperature drops by approximately 15°C (see the Thermal Shutdown section). Continuous Current Limit (MAX14523C) When the forward current reaches the forward-current threshold, the MAX14523C limits the output current to the programmed current limit. FLAG asserts if the current limit is present for tBLANK and deasserts when the overload condition is removed. In this mode, if die temperature exceeds +170°C (typ) due to self heating, the MAX14523C goes into thermal shutdown until the die temperature drops by approximately 15°C (see the Thermal Shutdown section). Table 1. Switch Truth Table MAX14523A MAX14523B MAX14523C MAX14523AL ON ON 0 1 Off 1 0 On SWITCH STATUS Switch-On/Off Control The ON input for the MAX14523A/MAX14523B/ MAX14523C and ON input for the MAX14523AL control the switch, see Table 1. Toggle ON for the MAX14523B to reset the fault condition once the short-circuit current is detected and the device shuts down. Reverse-Current Protection The MAX14523A/MAX14523AL/MAX14523B/MAX14523C feature a reverse-current protection circuit that limits the backflow current to 2µA when the reverse-current protection circuitry has tripped. The switch turns off and FLAG asserts without waiting for tBLANK to elapse. The switch turns back on and FLAG deasserts when VIN V OUT drops below the reverse-current threshold by 95mV (typ). FLAG Indicator FLAG is an open-drain fault indicator output and requires an external pullup resistor to a DC supply. FLAG goes low when any of the following conditions occur: • • The blanking time has elapsed The reverse-current protection has tripped • • The die temperature exceeds +170°C SETI is connected to ground. Thermal Shutdown Thermal-shutdown circuitry protects the devices from overheating. The switch turns off and FLAG goes low immediately when the junction temperature exceeds +170°C (typ). The switch turns on again after the device temperature drops by approximately 15°C (typ). Applications Information Setting the Current Limit/Threshold A resistor from SETI to ground programs the current limit/threshold value for the MAX14523A/MAX14523AL/ MAX14523B/MAX14523C. Table 2 lists various current limit/thresholds set by different resistor values at SETI. Leaving SETI unconnected selects a 0 current limit/threshold. Connecting SETI to ground asserts FLAG. Use the following formula to calculate the current limit: RSETI(kΩ) = 141400(V) − 2.48(kΩ) ILIM (mA) _______________________________________________________________________________________ 9 MAX14523A/MAX14523AL/MAX14523B/MAX14523C The autoretry feature saves system power in case of an overcurrent or short-circuit condition. During tBLANK time, when the switch is on, the supply current is held at the current limit. During time tRETRY, when the switch is off, the current through the switch is zero. Thus, the average output current is much less than the programmed current limit. Calculate the average output current using the following equation: MAX14523A/MAX14523AL/MAX14523B/MAX14523C 250mA to 1.5A, Adjustable Current-Limit Switches Table 2. Current Limit/Threshold vs. Resistor Values RSETI (k) TYPICAL CURRENT LIMIT/THRESHOLD (mA) 91.78 1500 121 1145 221 632 301 466 422 333 563.12 250 (Open) 0 Do not use an RSETI value smaller than 91.78kΩ. Note: Connecting any capacitance larger than 20pF to SETI can cause instability. change is minimal. If the output is continuously shorted to ground at the maximum supply voltage, the operation of the switches with the autoretry option does not cause problems because the total power dissipated during the short is scaled by the duty cycle: P(MAX) = VIN(MAX) × IOUT(MAX) × tBLANK tRETRY + tBLANK Attention must be given to the MAX14523C continuous current-limit version when the power dissipation during a fault condition can cause the device to reach the thermal shutdown threshold. Chip Information PROCESS: BiCMOS IN Bypass Capacitor Pin Configuration Connect a minimum of 1µF capacitor from IN to GND to limit the input voltage drop during momentary output short-circuit conditions. Larger capacitor values further reduce the voltage undershoot at the input. N.C. 1 FLAG 2 SETI 3 OUT 4 OUT Bypass Capacitor For stable operation over the full temperature range and over the full-programmable current-limit range, use a 1µF ceramic capacitor from OUT to ground. Excessive output capacitance can cause a false overcurrent condition due to decreased dv/dt across the capacitor. Calculate the maximum capacitive load (CMAX) value that can be connected to OUT using the following formula: CMAX (µF) = ILIM (mA) × tBLANK(MIN) (ms) VIN (V) To optimize the switch response time to output shortcircuit conditions, it is very important to keep all traces as short as possible to reduce the effect of undesirable parasitic inductance. Place input and output capacitors as close as possible to the device (no more than 5mm). IN and OUT must be connected with wide short traces to the power bus. During normal operation, the power dissipation is small and the package temperature 10 MAX14523A MAX14523AL MAX14523B MAX14523C *EP 8 GND 7 ON(ON)** 6 N.C. 5 IN TDFN 3mm x 3mm *CONNECT EXPOSED PAD TO GND. **( ) FOR THE MAX14523AL ONLY. For example, for VIN = 3.3V, tBLANK = 10ms, and ILIM = 300mA, CMAX equals 909µF. Layout and Thermal Dissipation + Package Information For the latest package outline information and land patterns, 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. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 TDFN-EP T833+2 21-0137 90-0059 ______________________________________________________________________________________ 250mA to 1.5A, Adjustable Current-Limit Switches REVISION NUMBER REVISION DATE 0 7/09 Initial release — 1 1/11 Added the MAX14523BATA automotive-grade part to the Ordering Information 1 DESCRIPTION PAGES CHANGED 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 ____________________ 11 © 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX14523A/MAX14523AL/MAX14523B/MAX14523C Revision History