(cid:25) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 (cid:1) Fast Transient Response 5-PIN TO-220 (cid:1) T PACKAGE (TOP VIEW) 10-mA to 5-A Load Current (cid:1) Short Circuit Protection (cid:1) Maximum Dropout of 500-mV at 5-A Load Current (cid:1) Separate Bias (VB) and VIN Pins (cid:1) Available in Adjustable or Fixed Output Voltages (cid:1) 5-Pin Package Allows Kelvin Sensing of Load Voltage 5-PIN TO-263 (cid:1) TD PACKAGE Reverse Current Protection (TOP VIEW) Note: Tab = Ground description The UC385 is a low dropout linear regulator providing a quick response to fast load changes. Combined with its precision onboard reference, the UC385 excels at driving GTL and BTL buses. Due to its fast response to load transients, the total capacitance required to decouple the regulator’s output can be significantly decreased when compared to standard LDO linear regulators. Dropout voltage (VIN to VOUT) is only 490 mV maximum and 350 mV typical at 5-A load (0°C to 100°C). The onboard bandgap reference is stable with temperature and scaled for a 1.2 V input to the internal power amplifier. The UC385 is available in fixed output voltages of 1.5 V, 2.1 V, or 2.5 V. The output voltage of the adjustable version can be set with two external resistors. If the external resistors are omitted, the output voltage defaults to 1.2 V. block diagram VB 1 R1 R2 UC382−ADJ OPEN 0 UC382−1 (1.5 V) 2 kΩ 500Ω UC382−2 (2.1 V) 2 kΩ 1.5 kΩ UC382−3 (2.5 V) 2 kΩ 2.16 kΩ THERMAL SHUTDOWN 2 VIN 1.2 V BANDGAP + REFERENCE SHORT R1 R2 CIRCUIT SENSE 3 5 4 GND ADJ VOUT UDG-00084 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of TexasInstruments semiconductor products and disclaimers thereto appears at the end of this data sheet. All trademarks are the property of their respective owners. (cid:20)(cid:16)(cid:21)(cid:11)(cid:1)(cid:2)(cid:15)(cid:18)(cid:21)(cid:17) (cid:11)(cid:10)(cid:15)(cid:10) (cid:26)(cid:27)(cid:28)(cid:29)(cid:30)(cid:31)!"(cid:26)(cid:29)(cid:27) (cid:26)# $%(cid:30)(cid:30)&(cid:27)" !# (cid:29)(cid:28) ’%()(cid:26)$!"(cid:26)(cid:29)(cid:27) *!"&+ Copyright  1998−2004, Texas Instruments Incorporated (cid:20)(cid:30)(cid:29)*%$"# $(cid:29)(cid:27)(cid:28)(cid:29)(cid:30)(cid:31) "(cid:29) #’&$(cid:26)(cid:28)(cid:26)$!"(cid:26)(cid:29)(cid:27)# ’&(cid:30) ",& "&(cid:30)(cid:31)# (cid:29)(cid:28) (cid:15)&-!# (cid:18)(cid:27)#"(cid:30)%(cid:31)&(cid:27)"# #"!(cid:27)*!(cid:30)* .!(cid:30)(cid:30)!(cid:27)"/+ (cid:20)(cid:30)(cid:29)*%$"(cid:26)(cid:29)(cid:27) ’(cid:30)(cid:29)$&##(cid:26)(cid:27)0 *(cid:29)&# (cid:27)(cid:29)" (cid:27)&$&##!(cid:30)(cid:26))/ (cid:26)(cid:27)$)%*& "&#"(cid:26)(cid:27)0 (cid:29)(cid:28) !)) ’!(cid:30)!(cid:31)&"&(cid:30)#+ POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 1

(cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:25) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 absolute maximum ratings over operating free-air temperature (unless otherwise noted)† VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 V Output voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 V to −6.0 V Storage temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C Junction temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −55°C to 150°C Lead temperature (soldering, 10 seconds) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300°C †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 under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. AVAILABLE OPTIONS(1) PACKAGED DEVICES TO-220 (T) TO−263 (TD)(2) TTJJ OUTPUT VOLTAGE OUTPUT VOLTAGE 1.5 V 2.1 V 2.5 V 1.2 V or ADJ 1.5 V 2.1 V 2.5 V 1.2 V or ADJ –40°C to 100°C 285T-1 285T-2 285T-3 285T-ADJ 285TD-1 285TD-2 285TD-3 285TD-ADJ 0°C to 100°C 385T-1 385T-2 385T-3 385T-ADJ 385TD-1 385TD-2 385TD-3 385TD-ADJ 1. For more package and ordering information, see the Package Option Addendum located at the end of this data sheet. 2. For 50 piece reel, add KTTT (e.g., UC285TDKTTT−1); for 500 piece reel, add TR (e.g., UC285TDTR−1). electrical characteristics unless otherwise stated, these parameters apply for T = −40°C to 100°C A for the UC285-x series and 0°C to 100°C for the UC385-x, VB = 5 V; VIN = 3.3 V, VOUT = 2.5 V, T = T . A J PARAMETER TEST CONDITION MIN TYP MAX UNIT UC385-3 Fixed 2.5 V, 5-A Family OOuuttppuutt vvoollttaaggee UC385-3 IVOUT = 100 mA 2.475 2.5 2.525 V UC285-3 IVOUT = 100 mA 2.45 2.5 2.525 V Load regulation IVOUT = 10 mA to 5 A 0.5 4 mV VIN PSRR 80 110 dB VB PSRR 50 65 dB VVIINN ddrrooppoouutt vvoollttaaggee ((VVIINN -- VVOOUUTT)) IVOUT = 5 A, TJ = 25°C 350 425 mV UC385-3 IVOUT = 5 A 350 490 mV UC285-3 IVOUT = 5 A 350 500 mV VVBB ddrrooppoouutt ((VVBB -- VVOOUUTT)) UC385-3 IVOUT = 5 A 1.8 2.1 V UC285-3 IVOUT = 5 A 1.8 2.2 V Short circuit current limit 5.1 7.5 A VVBB ccuurrrreenntt IVOUT = 10 mA 8 15 mA IVOUT = 5 A 40 100 mA VIN current IVOUT = 5 A 4.9 4.96 A UC385-2 Fixed 2.1 V, 5-A Family OOuuttppuutt vvoollttaaggee UC385-2 IVOUT = 100 mA 2.079 2.1 2.121 V UC285-2 IVOUT = 100 mA 2.058 2.1 2.121 V Load regulation IVOUT = 10 mA to 5 A 0.5 4 mV VIN PSRR 80 110 dB VB PSRR 50 67 dB 2 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

(cid:25) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 electrical characteristics unless otherwise stated, these parameters apply for T = −40°C to 100°C A for the UC285-x series and 0°C to 100°C for the UC385-x, VB = 5 V; VIN = 3.3 V, VOUT = 2.5 V, T = T . A J PARAMETER TEST CONDITION MIN TYP MAX UNIT UC385−2 Fixed 2.1 V, 5-A Family (continued) VVIINN ddrrooppoouutt vvoollttaaggee ((VVIINN -- VVOOUUTT)) IVOUT = 5 A, TJ = 25°C 350 425 mV UC385-2 IVOUT = 5 A 350 490 mV UC285-2 IVOUT = 5 A 350 500 mV VVBB ddrrooppoouutt ((VVBB -- VVOOUUTT)) UC385-2 IVOUT = 5 A 1.8 2.1 V UC285-2 IVOUT = 5 A 1.8 2.2 V Short circuit current limit 5.1 7.5 A VVBB ccuurrrreenntt IVOUT = 10 mA 8 15 mA IVOUT = 5 A 40 100 mA VIN current IVOUT = 5 A 4.9 4.96 A UC385−1 Fixed 1.5 V, 5-A Family OOuuttppuutt vvoollttaaggee UC385-1 IVOUT = 100 mA 1.485 1.5 1.515 V UC285-1 IVOUT = 100 mA 1.470 1.5 1.515 V Load regulation IVOUT = 10 mA to 5 A 0.5 4 mV VIN PSRR 80 110 dB VB PSRR 50 65 dB VVIINN ddrrooppoouutt vvoollttaaggee ((VVIINN -- VVOOUUTT)) IVOUT = 5 A, TJ = 25°C 350 425 mV UC285-1 IVOUT 5 A 350 490 mV UC285-2 IVOUT = 5 A 350 500 mV VVBB ddrrooppoouutt ((VVBB -- VVOOUUTT)) UC385-1 IVOUT = 5 A 1.8 2.1 V UC285-1 IVOUT = 5 A 1.8 2.2 V Short circuit current limit 5.1 7.5 A VVBB ccuurrrreenntt IVOUT = 10 mA 8 15 mA IVOUT = 5 A 40 100 mA VIN = current IVOUT = 5 A 4.9 4.96 A UC385-ADJ Adjustable, 5-A Family AADDJJ vvoollttaaggee UC385-ADJ IVOUT - 100 mA 1.188 1.2 1.212 V UC285-ADJ IVOUT - 100 mA 1.176 1.2 1.212 V Load regulation IVOUT = 10 mA to 5 A 0.5 4 mV VIN PSRR VOUT programmed for 2.5 V 80 110 dB VB PSRR VOUT Programmed for 2.5 V 50 65 dB VVIINN ddrrooppoouutt vvoollttaaggee ((VVIINN -- VVOOUUTT)) IVOUT = 5 A, TJ = 25°C 350 425 mV UC385-ADJ IVOUT = 5 A 350 490 mV UC285-ADJ IVOUT = 5 A 350 500 mV VVBB ddrrooppoouutt ((VVBB -- VVOOUUTT)) UC385-ADJ IVOUT = 5 A 1.8 2.1 V UC285-ADJ IVOUT = 5 A 1.8 2.2 V Short circuit current limit 5.1 7.5 A VVBB ccuurrrreenntt IVOUT = 10 mA 8 15 mA IVOUT = 5 A 40 100 mA VIN current IVOUT = 5 A 4.9 4.96 A POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 3

(cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:25) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 pin descriptions ADJ: In the adjustable version, the user programs the output voltage with two external resistors. The resistors should be 0.1% for high accuracy. The output amplifier is configured as a noninverting operational amplifier. The resistors should meet the criteria of R3 || R4 < 100 Ω. Connect ADJ to VOUT for an output voltage of 1.2 V. Note that the point at which the feedback network is connected to the output is the Kelvin sense point. GND: For accurate results, the GND pin should be referenced to the load ground. VB: Supplies power to all circuits of the regulator except the output power transistor. The 2-V headroom from VB to VOUT allows the use of a Darlington output stage for inherently low output impedance and fast response. (Dropout is derated for junction temperatures below 0°C.) VIN: Supplies the current to the collector of the output power transistor only. The dropout (VIN-VOUT) is under 100 mV for light loads; maximum dropout is 490 mV at 5 A for T = 0°C to 100°C. (Dropout is derated for junction J temperatures over 100°C.) VOUT: This pin should be connected to the load via a low impedance path. Avoid connectors which add significant inductance and resistance. Note that even though a Kelvin sense is available through a 5-pin package, care must be taken since voltage drops along wire traces add to the dropout voltage. DROPOUT VOLTAGE (VB − VOUT) DROPOUT VOLTAGE (VIN − VOUT) vs. vs. LOAD CURRENT LOAD CURRENT 1.7 400 V m TJ = 27°C − TJ = 27°C − V UT) UT) 1.675 VO O − V N 300 − VI VB e ( Voltage ( 1.65 ut Voltag out opo 200 p Dr Dro 1.625 O - − D O V D V 1.6 100 0 1 2 3 4 5 100m 5 IL− Load Current − A IL− Load Current − A Figure 1 Figure 2 4 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

(cid:25) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 APPLICATION INFORMATION The UC385 is easy to use. The adjustable version requires two resistors to set the output voltage. The fixed versions of the UC385 require no external resistors. All versions of the UC385 require decoupling capacitors on the input and output. In a typical application, VB and VIN are driven from switching power supplies which may have large filter capacitors at their outputs. If the UC385 is further than 12 inches from the power supply, it is recommended to add local decoupling as close as possible to the linear regulator. Decouple the output of the UC385 with at least 100 µF of high quality tantalum or Sanyo OSCON capacitors close to the VOUT pin for maximum stability. Many applications involving ultrafast GTL or BTL applications require additional capacitance close to the load. The exact amount will vary according to speed and magnitude of the load transients and the tolerance allowed for transients on VOUT. When specifying the decoupling capacitors, the series resistance of the capacitor bank is an important factor in its ability to filter load transients. The UC385 allows for Kelvin sensing the voltage at the load. This improves regulation performance and eliminates the voltage drops due to wire trace resistance. This voltage drop must be added to the headroom (VIN to VOUT and VB to VOUT). The dropout of 350 mV is measured at the pins and does not include additional drops due to trace resistance. OPEN LOOP PHASE OPEN LOOP GAIN vs. vs. FREQUENCY FREQUENCY 0 70 CO = 100 µF 60 CO = 100 µF IL = 1 A IL = 1 A 50 40 eg B d d e - −90 n - 30 has Gai P 20 10 0 −180 −10 100 1 k 10 k 100 k 1 M 10 M 100 1 k 10 k 100 k 1 M 10 M f − Frequency − Hz f − Frequency − Hz Figure 3 Figure 4 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 5

(cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:25) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 APPLICATION INFORMATION POWER SUPPLY REJECTION RATIO (VB INPUT) vs. FREQUENCY B d 60 − ut) p B In 50 V o ( ati 40 R n o cti e 30 ej R y pl p u 20 S r e w o R - P 10 S S P 0 100 1 k 10 k 100 k 1 M 10 M f − Frequency − Hz Figure 5 + 1µ F _ Ceramic 5 V 1 VB VO = 1.2 V IRF 2 VIN VOUT 4 520 + + + UC385−ADJ 100µF 121Ω Pulse _ 4.7µ F Tantalum R1 Generator Tantalum ADJ 5 3.3 V GND 3 UDG-00085 Figure 6. Transient Test Circuit 6 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

(cid:25) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 APPLICATION INFORMATION 10 mA to 3 A/µs Load Transient Response 20 V nm e i− 10 ge ng Chaolta 0 V− Oput V −10 ∆ ut O −20 3 A − 2 nt e r r u 1 C d a o L 0 − O I 2 µs/DIV Figure 7 +5 V + 4.7µF Kelvin Sense Point 1 +3.3 V VB +1.8 V 2 VIN VOUT 4 Output + 4.7µF UC385−ADJ 6R0 3Ω +330µF C2e.2raµmFic OSCON ADJ 5 GND R4 3 120Ω UDG-00086 Figure 8. Typical UC385-ADJ Application POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 7

(cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:3)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:3)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:9)(cid:8) (cid:1)(cid:2)(cid:9)(cid:4)(cid:5)(cid:6)(cid:10)(cid:11)(cid:12) (cid:25) (cid:13)(cid:10)(cid:14)(cid:15) (cid:15)(cid:16)(cid:10)(cid:17)(cid:14)(cid:18)(cid:19)(cid:17)(cid:15) (cid:16)(cid:19)(cid:14)(cid:20)(cid:21)(cid:17)(cid:14)(cid:19) (cid:5)(cid:6)(cid:10) (cid:22)(cid:21)(cid:23)(cid:6)(cid:11)(cid:16)(cid:21)(cid:20)(cid:21)(cid:1)(cid:15) (cid:16)(cid:19)(cid:24)(cid:1)(cid:22)(cid:10)(cid:15)(cid:21)(cid:16) SLUS212E − NOVEMBER 1999 − REVISED FEBRUARY 2004 APPLICATION INFORMATION +5 V Kelvin Sense + 4.7µF 1 Point VB +1.5 V 2 VIN VOUT 4 Output UC385−1 +330µF 2.2µF OSCON Ceramic ADJ 5 GND 3 UDG-00087 Figure 9. Typical UC385-1, -2, or -3 Application 8 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

PACKAGE OPTION ADDENDUM www.ti.com 20-Feb-2004 PACKAGING INFORMATION ORDERABLEDEVICE STATUS(1) PACKAGETYPE PACKAGEDRAWING PINS PACKAGEQTY UC285T-1 ACTIVE TO/SOT KC 5 50 UC285T-2 ACTIVE TO/SOT KC 5 50 UC285T-3 ACTIVE TO/SOT KC 5 50 UC285T-ADJ ACTIVE TO/SOT KC 5 50 UC285TD-1 OBSOLETE PFM KTT 5 UC285TD-2 OBSOLETE PFM KTT 5 UC285TD-3 OBSOLETE PFM KTT 5 UC285TD-ADJ OBSOLETE PFM KTT 5 UC285TDKTTT-1 ACTIVE PFM KTT 5 50 UC285TDKTTT-2 ACTIVE PFM KTT 5 50 UC285TDKTTT-3 ACTIVE PFM KTT 5 50 UC285TDKTTT-ADJ ACTIVE PFM KTT 5 50 UC285TDTR-1 ACTIVE PFM KTT 5 500 UC285TDTR-2 ACTIVE PFM KTT 5 500 UC285TDTR-3 ACTIVE PFM KTT 5 500 UC285TDTR-ADJ ACTIVE PFM KTT 5 500 UC385T-1 ACTIVE TO/SOT KC 5 50 UC385T-2 ACTIVE TO/SOT KC 5 50 UC385T-3 ACTIVE TO/SOT KC 5 50 UC385T-ADJ ACTIVE TO/SOT KC 5 50 UC385TD-1 OBSOLETE PFM KTT 5 UC385TD-2 OBSOLETE PFM KTT 5 UC385TD-3 OBSOLETE PFM KTT 5 UC385TD-ADJ OBSOLETE PFM KTT 5 UC385TDKTTT-1 ACTIVE PFM KTT 5 50 UC385TDKTTT-2 ACTIVE PFM KTT 5 50 UC385TDKTTT-3 ACTIVE PFM KTT 5 50 UC385TDKTTT-ADJ ACTIVE PFM KTT 5 50 UC385TDTR-1 ACTIVE PFM KTT 5 500 UC385TDTR-2 ACTIVE PFM KTT 5 500 UC385TDTR-3 ACTIVE PFM KTT 5 500 UC385TDTR-ADJ ACTIVE PFM KTT 5 500 UC385TH-ADJ OBSOLETE TO/SOT KC 5 (1)Themarketingstatusvaluesaredefinedasfollows: ACTIVE:Productdevicerecommendedfornewdesigns. LIFEBUY:TIhasannouncedthatthedevicewillbediscontinued,andalifetime-buyperiodisineffect. NRND:Notrecommendedfornewdesigns.Deviceisinproductiontosupportexistingcustomers,butTIdoesnotrecommendusingthispartin anewdesign. PREVIEW:Devicehasbeenannouncedbutisnotinproduction.Samplesmayormaynotbeavailable. OBSOLETE:TIhasdiscontinuedtheproductionofthedevice.

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MECHANICAL DATA MSOT008B – JANUARY 1995 – REVISED SEPTEMBER 2000 KC (R-PSFM-T5) PLASTIC FLANGE-MOUNT 0.420 (10,67) 0.113 (2,87) 0.185 (4,70) 0.156 (3,96) DIA 0.380 (9,65) 0.103 (2,62) 0.175 (4,46) 0.146 (3,71) 0.055 (1,40) 0.045 (1,14) 0.147 (3,73) 0.137 (3,48) 0.340 (8,64) 0.330 (8,38) 1.037 (26,34) 0.125 (3,18) 0.997 (25,32) (see Note C) 1 5 0.040 (1,02) 0.122 (3,10) 0.067 (1,70) 0.030 (0,76) 0.102 (2,59) 0.010 (0,25) M 0.268 (6,81) 0.025 (0,64) 0.012 (0,30) 4040208/E 09/00 NOTES: A. All linear dimensions are in inches (millimeters). B. This drawing is subject to change without notice. C. Lead dimensions are not controlled within this area. D. All lead dimensions apply before solder dip. E. The center lead is in electrical contact with the mounting tab. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 1

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