general description the MAX1607 is a current-limited 60m ? switch with built-in fault blanking. its accurate, preset 0.7a to 1.0a current limit makes it ideal for usb applications. its low quiescent supply current (14?) and standby current (1?) conserve battery power in portable applications. the MAX1607 operates with inputs from +2.7v to +5.5v, making it ideal for both 3v and 5v systems. an overcurrent signal ( oc ) notifies the microprocessor that the internal current limit has been reached. a 10ms overcurrent-blanking feature allows momentary faults (such as those caused when hot-swapping into a capacitive load) to be ignored, thus preventing false alarms to the host system. this blanking also prevents an oc signal from being issued when the device is powering up. the MAX1607 has several safety features to ensure that the usb port is protected. built-in thermal-overload pro- tection limits power dissipation and junction tempera- ture. the device also has accurate internal current- limiting circuitry to protect the input supply against overload. the MAX1607 is a pin-compatible upgrade to texas instruments?tps2014, tps2015, and tps2041 for usb applications. the same die is available in a space-saving 10-pin ?ax package (max1693) and can be used for next-generation designs. the max1694 is similar to the max1693, but it has a built-in latch that turns off the power switch in case of a long-term short-circuit condi- tion. applications notebook computers usb ports usb hubs docking stations features pin compatible with tps2014, tps2015, and tps2041 accurate current limit (0.7a min, 1.0a max) guaranteed 0.75a short-circuit protection 10ms internal oc blanking timeout no overcurrent ( oc ) signal during power-up 125m ? max high-side mosfet 500ma continuous current short-circuit and thermal protection with overcurrent logic output 1ms start-up time undervoltage lockout 14? quiescent supply current 1? max standby supply current +2.7v to +5.5v supply range ul approved ?#e211935 MAX1607 usb current-limited switch in pin-compatible package ________________________________________________________________ maxim integrated products 1 out 1 2 8 7 out out in in gnd so top view 3 4 6 5 MAX1607 oc en MAX1607 in output out input +2.7v to +5.5v on off gnd oc en typical operating circuit 19-1544; rev 1; 11/00 part MAX1607esa -40? to +85? temp. range pin-package 8 so pin configuration ordering information for price, delivery, and to place orders, please contact maxim distribution at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com.
MAX1607 usb current-limited switch in pin-compatible package 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics (v in = +5v, t a = 0 c to +85 c, unless otherwise noted. typical values are at t a = +25?.) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. in, en , oc to gnd .....................................................-0.3 to +6v out to gnd ................................................-0.3v to (v in + 0.3v) maximum switch current.........................1.2a (internally limited) out short-circuit to gnd ..........................................continuous continuous power dissipation (t a = +70?) 8-pin so (derate 5.88mw/? above +70?)................471mw operating temperature range (extended) .........-40? to +85? storage temperature range .............................-65? to +150? lead temperature (soldering, 10s) .................................+300? t a = 0? to +85? v en = v in = 5.5v, v out = gnd timer running v en = v in = v out = 5.5v out shorted to gnd force v out to 4.5v v in = 3.7v to 5.5v v in = 2.7v to 3.6v v in = 5v, c out = 150? from en driven low to 50% full v out i load = 400ma t a = +25? t a = 0? to +85? v en = v in or gnd i load = 400ma v in = 2.7v to 5.5v conditions ? 15 supply leakage current 0.01 2 ? 35 i q supply current, high-level input 14 25 ? 0.001 1 supply current, low-level input ma 500 700 i sc short-circuit output current ma 700 850 1000 i limit overload output current ms 1 start-up time ? -1 1 en input current v 0.8 v il en low-level input voltage v 2.7 5.5 v in input voltage v 2.4 v ih en high-level input voltage 2.0 ? 3620 t off switch turn-off time 60 90 125 m ? 72 150 r ds( on) switch static drain-source on-state resistance ? 80 200 t on switch turn-on time units min typ max symbol parameter v in = v oc = 5v i sink = 1ma, v in = 3v rising edge, 100mv hysteresis from overcurrent condition to oc assertion ? +165 thermal shutdown threshold ms 71013 t bl oc blanking timeout period ? 1 oc off-state current v 0.4 v ol oc output low voltage v 2.0 2.4 2.6 uvlo undervoltage lockout v in = 4.4v to 5.5v v in = 4.4v to 5.5v v in = 3v timer not running v en = gnd, i out = 0 t a = +25? operating condition power switch enable input ( en ) current limit supply current undervoltage lockout overcurrent ( oc ) thermal shutdown
MAX1607 usb current-limited switch in pin-compatible package _______________________________________________________________________________________ 3 note 1: specifications to -40? are guaranteed by design, not production tested. electrical characteristics (v in = +5v, t a = -40 c to +85 c, unless otherwise noted.) (note 1) v in = v oc = 5v i sink = 1ma, v in = 3v rising edge, 100mv hysteresis v en = v in = 5.5v, v out = gnd v en = gnd, i out = 0, timer not running v en = v in = v out = 5.5v v in = 3.0v to 5.5v v in = 3.7v to 5.5v out shorted to gnd force v out to 4.5v v in = 3.0v to 3.6v v in = 4.4v to 5.5v v in = 3v i load = 400ma i load = 400ma v en = v in or gnd conditions ? 1 oc off-state current v 0.4 v ol oc output low voltage v 2.0 2.9 uvlo undervoltage lockout ? 15 supply leakage current ? 25 i q supply current, high-level input ? 2 supply current, low-level input ma 750 i sc short-circuit output current ma 640 1060 i limit overload output current ? -1 1 en input current v 3.0 5.5 v in input voltage v 0.8 v il en low-level input voltage v 2.4 v ih en high-level input voltage 2.0 125 m ? 150 r ds( on) switch static drain-source on-state resistance ? 200 t on switch turn-on time ? 120 t off switch turn-off time units min typ max symbol parameter oc blanking timeout period t bl from overcurrent condition to oc assertion 614 ms operating condition power switch enable input ( en ) current limit supply current undervoltage lockout overcurrent ( oc )
MAX1607 usb current-limited switch in pin-compatible package 4 _______________________________________________________________________________________ typical operating characteristics (v in = +5v, t a = +25?, unless otherwise noted.) 0 2 4 6 8 10 12 14 16 02 1 3456 quiescent current vs. input voltage MAX1607-01 input voltage (v) quiescent current ( a) i out = 0 v en = gnd 9 11 10 13 12 15 14 16 -40 0 20 -20 40 60 80 100 quiescent current vs. temperature MAX1607-02 temperature (?) quiescent current ( a) v in = 5v v in = 3v 100 0.01 off supply current vs. temperature 0.1 1 10 MAX1607-03 temperature ( c) off supply current (na) -40 0 -20 20 40 60 80 100 v en = v in 0 40 20 80 60 140 120 100 160 -40 0 -20 20 40 60 80 100 turn-on time vs. temperature MAX1607-07 temperature ( c) t on ( s) i load = 425ma v in = 3v v in = 5v 0 2 1 4 3 6 5 7 -40 0 20 -20 40 60 80 100 turn-off time vs. temperature MAX1607-08 temperature ( c) t off ( s) i load = 425ma v in = 3v v in = 5v 0 2 6 4 10 8 12 -40 0 20 -20 40 60 80 100 fault-blanking timeout vs. temperature MAX1607-09 temperature ( c) fault-blanking timeout (ms) i out = 850ma v in = 3v or 5v 100 1000 0.01 -40 0 -20 40 100 80 off switch current vs. temperature 0.1 1 10 MAX1607-04 temperature ( c) off switch current (na) 20 60 v en = v in -40 0 -20 40 100 80 normalized on-resistance vs. temperature MAX1607-05 temperature ( c) normalized r on 20 60 0 0.4 0.2 0.8 0.6 1.2 1.0 1.4 i out = 425ma 0 0.4 0.2 0.8 0.6 1.0 1.2 023 1 456 normalized output current vs. output voltage MAX1607-06 output voltage (v) normalized output current short-circuit current i limit
MAX1607 usb current-limited switch in pin-compatible package _______________________________________________________________________________________ 5 ch4 ch3 ch1 ch2 2ms/div MAX1607-10 current-limit and oc response ch1 = v in , 200mv/div, ac-coupled ch2 = v out , 5v/div ch3 = v oc , 5v/div ch4 = i out , 500ma/div ch4 10 s/div ch3 ch1 ch2 current-limit response MAX1607-11 ch1 = v in , 200mv/div, ac-coupled ch2 = v out , 5v/div ch3 = v oc , 5v/div ch4 = i out , 1a/div ch4 ch3 ch2 ch1 switch turn-on time MAX1607-12 20 s/div ch1 = v out , 5v/div ch2 = v en , 5v/div ch3 = v oc , 5v/div ch4 = i out , 200ma/div ch4 ch3 ch2 ch1 switch turn-off time MAX1607-13 1 s/div ch1 = v out , 5v/div ch2 = v en , 5v/div ch3 = v oc , 5v/div ch4 = i out , 200ma/div start-up time (typical usb application) MAX1607-14 v in = 5v, r l = 15 ?, c l = 150 f ch1 = v out , 5v/div ch2 = v en , 5v/div ch3 = i in , 500ma/div ch4 = v oc , 5v/div 1ms/div ch2 ch3 ch4 ch1 full current limit charges capacitor resistor load current short-circuit current limit typical operating characteristics (continued) (v in = +5v, t a = +25?, unless otherwise noted.)
MAX1607 usb current-limited switch in pin-compatible package 6 _______________________________________________________________________________________ detailed description the MAX1607 p-channel mosfet power switch limits output current to 0.7a min and 1.0a max. when the out- put current is increased beyond the current limit (i limit ), the current also increases through the replica switch (i out / 6500). the current-limit error amplifier compares the voltage to the internal 1.24v reference and regu- lates the current back to the i limit (figure 1). these switches are not bidirectional; therefore, the input voltage must be higher than the output voltage. continuous short-circuit protection the MAX1607 is a short-circuit-protected switch. in the event of an output short-circuit condition, the current through the switch is foldback-current-limited to 500ma continuous. thermal shutdown the MAX1607 has a thermal shutdown feature. the switch turns off and the oc output goes low immediate- ly (no overcurrent blanking) when the junction tempera- ture exceeds +165?. when the MAX1607 cools 20?, the switch turns back on. if the fault short-circuit condi- tion is not removed, the switch will cycle on and off, resulting in a pulsed output. oc indicator the MAX1607 provides an overcurrent output ( oc ). a 100k ? pull-up resistor from oc to in provides a logic control signal. this open-drain output goes low when any of the following conditions occur: ? the input voltage is below the 2.4v undervoltage- lockout (uvlo) threshold. ? the die temperature exceeds the thermal shutdown temperature limit of +165?. ? the device is in current limit for greater than 10ms. oc blanking the MAX1607 features 10ms overcurrent blanking. blanking allows brief current-limit faults, including momentary short-circuit faults that occur when hot- swapping a capacitive load, and also ensures that no oc is issued during power-up. when a load transient causes the device to enter current limit, an internal counter starts. if the load fault persists beyond the 10ms overcurrent-blanking timeout, the oc output asserts low. ensure that the MAX1607 input is ade- quately bypassed to prevent input glitches from trigger- ing spurious oc outputs. input voltage glitches less name function 1 gnd ground 2, 3 in input. p-channel mosfet source?onnect all in pins together and bypass with a 1? capacitor to ground. pin 4 en active-low switch enable input. a logic low turns on the switch. 5 oc overcurrent-indicator output. this open-drain output goes low when the device is in thermal shutdown or undervoltage lockout, or during a sustained (>10ms) current-limit condition. 6, 7, 8 out switch output. p-channel mosfet drain?onnect all out pins together and bypass with a 0.1? capacitor to ground. pin description MAX1607 p p p out gnd 1.24v n on current-limit amplifier replica amplifier on en hot in control circuitry oc 10ms timer figure 1. functional diagram
MAX1607 usb current-limited switch in pin-compatible package than 150mv will not cause a spurious oc output. load- transient faults less than 10ms (typ) will not cause an oc output assertion. only current-limit faults are blanked. die overtempera- ture faults and input voltage droops below the uvlo threshold will cause an immediate oc output. applications information input capacitor to limit the input voltage drop during momentary output short-circuit conditions, connect a capacitor from in to gnd. a 1? ceramic capacitor will be adequate for most applications; however, higher capacitor values will further reduce the voltage drop at the input (figure 2). output capacitor connect a 0.1? capacitor from out to gnd. this capacitor helps to prevent inductive parasitics from pulling out negative during turn-off. layout and thermal dissipation important: optimize the switch response time to output short-circuit conditions by keeping 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 away). all in and out pins must be connected with short traces to the power bus. wide power-bus planes will provide superior heat dissipation through the MAX1607? in and out pins. under normal operating conditions, the package can dissipate and channel heat away. calculate the maxi- mum power dissipation as follows: p = (i limit ) 2 ? r on where i limit is the preset current limit (1.0a max) and r on is the on-resistance of the switch (125m ? max). when the output is short circuited, foldback-current lim- iting activates and the voltage drop across the switch equals the input supply. the power dissipated across the switch increases, as does the die temperature. if the fault condition is not removed, the thermal-over- load-protection circuitry activates (see thermal shutdown section). wide power-bus planes connected to in and out and a ground plane in contact with the device will help dissipate additional heat. figure 2. typical application circuit MAX1607 in output out input 1 f 0.1 f * * usb specifications require a higher value capacitor. overcurrent output on 100k off gnd oc en chip information transistor count: 715 _______________________________________________________________________________________ 7
MAX1607 usb current-limited switch in pin-compatible package maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 8 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2000 maxim integrated products printed usa is a registered trademark of maxim integrated products. package information soicn.eps
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