800ma low dropout regulator scsi-ii active terminator clm1117 features guaranteed 800ma output three terminal adjustable or fixed 2.85v, 3v, 3.3v, 5v, 10v & 12v very low quiescent current low dropout voltage of 1.2 volts at full load extremely tight load and line regulation very low temperature coefficient fixed 2.8v device for scsi-ii active terminator logic-controlled electronic shutdown internal overcurrent limiting & thermal overload protection surface mount package sot-223 applications scsi-ii active terminator portable/ palm top / notebook computers battery chargers disk drives portable consumer equipment portable instrumentation smps post-regulator product description the calogic clm1117 is a low power positive voltage regulator designed to meet 800ma output current and comply with scsi-ii specifications with a fixed output voltage of 2.85v. this device is an excellent choice for use in battery- powered applications, as active terminators for the scsi bus, and portable computers. the clm1117 features very low quiescent current and very low dropout voltage of 1.2v at a full load and lower as output current decreases. this product is available as an adjustable or fixed 2.85v, 3v, 3.3v, and 5v output voltages. the device is offered in a 3-pin surface mount package sot-223. the output capacitor of 10 m f or larger is needed for output stability of clm1117 as required by most of the other regulator circuits. ordering information part package temperature clm1117m sot-223 industrial clm1117m-x sot-223 industrial x = output voltage. 5v = standard. contact factory for 2.85v, 3.0v, 3.3v, 10v and 12v. corporation pin connections sot-223 tab is clm1117 adj./gnd v out v in 123 1n-12a front view v out calogic corporation, 237 whitney place, fremont, california 94539, telephone: 510- 656-2900, fax: 510-651-3025
absolute maximum ratings power dissipation . . . . . . . . . . . . . . . . . . . . . internally limited lead temp. (soldering, 5 seconds) . . . . . . . . . . . . . . . 260 o c storage temperature range . . . . . . . . . . . . -65 o c to +150 o c operating junction temperature range clm1117 . . . . . . . . . . . . . . . . . . . . . . . . . . -40 o c to +125 o c input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5v to 6v input supply voltage . . . . . . . . . . . . . . . . . . . . . . -20v to +20v esd rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2kv min clm1117 calogic corporation, 237 whitney place, fremont, california 94539, telephone: 510- 656-2900, fax: 510-651-3025 corporation electrical characteristics : v in = v out +1, t a = 25 o c, cl = 3.3 m f, unless otherwise noted. boldface apply over full operating temperature range. parameter typ min max units conditions output voltage 2.85 2.85 2.85 3.0 3.0 3.30 3.30 5.0 5.0 2.82 2.79 2.79 2.97 2.94 3.27 3.24 4.95 4.90 2.88 2.91 2.91 3.03 3.06 3.33 3.36 5.05 5.10 v i out = 10ma, i in = 4.85v 0 i out 800ma, 4.25 v in 10v 0 i out 500ma, v in = 4.05v i out = 10ma, v in = 5.00v 0 i out 800ma, 4.50 v in 10v i out = 10ma, i in = 5.30v 0 i out 800ma, 4.80 v in 10v i out = 10ma, i in = 7.00v 0 i out 800ma, 6.50 v in 12v output voltage temperature stability 0.05 % (note 1) line regulation 1.00 1.00 1.00 1.00 6.00 7.00 7.00 10.00 mv 4.25v v in 10v, v out = 2.85, i out = 0 4.50v v in 12v, v out = 3.00, i out = 0 4.80v v in 12v, v out = 3.30, i out = 0 4.50v v in 15v, v out = 5.00, i out = 0 load regulation 1.00 1.00 1.00 1.00 10.00 12.00 12.00 15.00 mv 0 i out 800ma, v in = 4.25v, v out = 2.85 0 i out 800ma, v in = 4.50v, v out = 3.00 0 i out 800ma, v in = 4.80v, v out = 3.30 0 i out 800ma, v in = 6.50v, v out = 5.00 dropout voltage (note 2) 1.00 1.05 1.10 1.10 1.15 1.20 v i l = 100ma i l = 500ma i l = 800ma quiescent voltage 5.00 10.00 ma 4.25v v in 6.5v current limit 800 950 1200 ma (v in - v out ) = 5v thermal regulation 0.01 0.1 %/w 25 o c, 30ms pulse ripple rejection 60 75 db f ripple = 120hz, (v in - v out ) = 3v, v ripple = 1v p-p long term stability 0.03 % 125 o c, 1000hrs rms output noiase 0.003 % % of v out , 10hz f 10khz thermal resistance 15 o c/w o junction to case, at tab note 1: output temperature coefficient is defined as the worst case voltage change divided by the total temperature range. note 2: dropout voltage is defined as the input to output differential at which the output voltage drops 100mv below its nominal valu e measured at 1v differential at very low values of programmed output voltage, the minimum input supply voltage of 2v (2.3v over temperatu re) must be taken input account. note 3: thermal regulation is defined as the change in output voltage at a time t after a change in power dissipation is appli ed, excluding load or line regulation effect.
application notes external capacitor to ensure the stability of the clm1117 an output capacitor of at least 10 m f (tantalum) or 50 m f (aluminum) is required. the value may change based on the application requirements on the output load or temperature range. the capacitor equivalent series resistance (esr) will effect the clm1117 stability. the value of the esr can vary from the type of capacitor used in the applications. the recommended value for esr is 0.5 w . the output capacitance could increase in size to above the minimum value. the larger value of output capacitance as high as 100 m f can improve the load transient response. soldering methods the clm1117 sot-223 package is designed to be compatible with infrared reflow or vapor-phase reflow soldering techniques. during soldering the non-active or mildly active fluxes may be used. the clm1117 die is attached to the heatsink lead which exits opposite the input, output, and ground pins. hand soldering and wave soldering should be avoided since these methods can cause damage to the device with excessive thermal gradients on the package. the sot-223 recommended soldering method are as follows: vapor phase reflow and infrared reflow with the component preheated to within 65 o c of the soldering temperature range. thermal characteristics the thermal resistance of clm1117 is c o /w from junction to tab and 31 c o /w from tab to ambient for a total of 46 c o /w from junction to ambient. the clm1117 features the internal thermal limiting to protect the device during overload conditions. special care needs to be taken during continuous load conditions to insure the maximum junction temperature does not exceed 125 o c. taking the fr-4 printed circuit board and 1/16 thick with 1 ounce copper foil as an experiment (fig.1 & fig.2), the pcb material is effective at transmitting heat with the tab attached to the pad area and a ground plane layer on the backside of the substrate. refer to table 1 for the r esults of the experiment. the thermal interaction from other components in the application can ef fect the thermal resistance of the clm1117. the actual thermal resistance can be determined with experimentation. clm1117 power dissipation is calculated as follows: p d = (v in - v out ) (i out ) maximum junction temperature range: t j = t ambient (max) + p d (thermal resistance (junction-to-ambient)) maximum junction temperature must not exceed 125 o c. p o = (10v - 2.85) (105ma) = (7.15) (105ma) = 750mw clm1117 corporation figure 1. circuit layout, thermal experiments 10v + 10 m f 2.85v 27k w 10 m f clm1117 - 2.85 1n-13 calogic corporation, 237 whitney place, fremont, california 94539, telephone: 510- 656-2900, fax: 510-651-3025 figure 2. substrate layout for sot-223 50 x 50mm 35 x 17mm 16 x 10mm 1n-14 table 1. total pc board area topside copper area backside copper area thermal resistance junction to ambient 2500mm 2500mm 2500mm 2500mm 2500mm 1600mm 2500mm 2500mm 1600mm 900mm 900mm 2500mm 1250mm 950mm 2500mm 1800mm 600mm 1250mm 915mm 600mm 240mm 240mm 2500mm 2500mm 2500mm 0 0 1600mm 0 0 0 900mm 0 46 o c/w o 47 o c/w o 49 o c/w o 51 o c/w o 53 o c/w o 55 o c/w o 58 o c/w o 59 o c/w o 67 o c/w o 72 o c/w o 85 o c/w o
active vs passive termination the improvement in noise immunity and low quiescent power of the terminator of less than 1w is the key advantage of active termination compared to passive termination. the clm1117 significantly improves the noise level and signals on the bus by the terminating point due to variat ions in voltage at the termination point due to variation in the v term power line. another advantage of active termination is the improvement in the impedance matching. the low impedance of the device makes the termination resistance more closely matched to the impedance of the cable. this improvement increases the data rate by 10 times, from 1mbyte/s to 10mbyte/s. the clm1117 increases the protection and the reliability of the application since it features internal current limiting, overvoltage protection, and thermal protection. clm1117 active termination configuration 5v in5817 termpwr clm1117-2.85 10 m f 2.85v 110k w + 6 meters max 10 m f 5v in5817 clm1117-2.85 10 m f 2.85v 110k w + 10 m f 110k w 6 meters max 110k w 110k w 110k w up to 27 lines + + 1n-15 corporation
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