AME, Inc. AT9173 Bus Termination Regulator n General Description n Features ● Support The AT9173 is a voltage regulator which could convert the input voltage ranging from 1.8V to 5V to an output voltage that user settled. The regulator can provide sourcing or sinking current.The AT9173, used in conjunction with series termination resistors, provides an excellent voltage source for active termination schemes of high speed transmission lines as those seen in high speed memory buses and distributed backplane designs. Both DDR I (1.25VTT) and DDR II (0.9VTT) Requirements ● Capable Current-limiting Protection ● Thermal Protection ● Integrated Power MOSFETs ● Generates Termination Voltages for SSTL-2 ● High The voltage output of the regulator can be used as a termination voltage for DDR SDRAM. of Sourcing and Sinking Current ● Accuracy Output Voltage at Full-Load ● Adjustable VOUT by External Resistors ● Minimum External Components ● Shutdown Current limits in both sourcing and sinking mode, plus on-chip thermal shutdown make the circuit tolerant of the output fault conditions. for Standby or Suspend Mode Operation with High-impedance Output n Applications ● DDRI/DDRII Memory Termination Supply ● Active Termination Buses ● Desktop PC,NoTebook,Server and workstation ● Graphic Card ● Set ● Top Box Embedded System n Typical Application AT9173 A-SOP 8 DDR _2.5 V 1 R2 100KO C4 0.1 uF C2 470uF 2 3 4 R4 100KO Rev. C.04 VIN VCNTL GND VCNTL REFEN VCNTL VOUT VCNTL AT9173A SOP-8 VCC_ 3.3 V 8 7 6 DDR_VTT 1.25V/1.5A 5 C8 4.7uF C6 470uF 1 AME, Inc. Bus Termination Regulator AT9173 n Typical Application(Contd.) VIN NC GND NC C3 0.1uF C4 470uF 2 REFEN 3 4 R3 100KO VOUTL GND _PAD 1 R1 100 KO VCC_ 3.3V AT9173 E-SOP 8 / PP DDR_2.5V VCNTL 8 7 6 DDR_ VTT 1 .25V/2A NC 5 C7 4.7uF AT9173E SOP-8/PP C5 470uF n Function Block Diagram VCNTL VIN Thermal Sensor + VOUT Thermal & Over Current Protection Circuit VCNTL REFEN + GND 2 Rev. C.04 AME, Inc. AT9173 Bus Termination Regulator n Pin Configuration SOP- 8 Top View 8 7 6 SOP- 8/PP Top View 5 AT9173 1 2 3 4 AT9173A 1. IN 2. GND 3. REFEN 4. OUT 5. VCNTL 6. VCNTL 7. VCNTL 8. VCNTL 8 7 6 5 AT9173 1 2 3 4 AT9173E 1. IN 2. GND 3. REFEN 4. OUT 5. NC 6. VCNTL 7. NC 8. NC n Pin Description Pin name IN GND Pin Description Input voltage pin which supplies current to the V OUT pin. Connect this pin to a welldecoupled voltage to prevent the input rail from dropping during large load transient. A large and low ESR capacitor is recommended to use that should be placed as close as possible to the V IN pin. Ground pin. Tie directly to ground plance. VCNTL Voltage control pin which supplies the internal control circuitry and provides the drive voltage. The driving capability of output current is proportioned to the VCNTL. Connect this pin to 5V bias supply to handle large output current with at least 1uF capacitor from this pin to GND. An important note is that VIN should be kept lower or equal to VCNTL. REFEN Reference voltage input and active low shutdown control pin. Two resistors dividing down the VIN voltage on this pin to create the regulatedoutput voltage. Pulling this pin to GND to turn off the device by an open-drain, such as 2N7002 N-Channel MOSFET. OUT Regulator output. V OUT is regulated from REFEN voltage that is used to terminate the bus resistors. It is capable of sinking and sourcing current while regulating the output rail. To maintain adequate large signal transient response, typical value of 1000uF electrolytic capacitor with 10uF ceramic capacitors are recommended to reduce the effects of current transients on VOUT. NC* No Connection. Not internal connected. GND Pad* Connected to GND plance for better heat dissipation. * By SOP-8/PP only Rev. C.04 3 AME, Inc. Bus Termination Regulator AT9173 n Ordering Information Part Number Marking Output Voltage Package AT9173AG AT9173AG yyww* AB xxxxxxx##** ADJ SOP-8 Operating Temp. Range o o -25 C to +85 C AT9173EG AT9173EG yyww* AC xxxxxxx##** ADJ SOP-8/PP Note: * yy and ww represents the data code. ** XXXXXXX represents the wafer lot number, ## represents the wafer number 4 Rev. C.04 AME, Inc. AT9173 Bus Termination Regulator n Absolute Maximum Ratings Parameter Symbol Maximum Unit VIN 6 V VCNTL to GND VCNTL 6 V ESD Rating (Human Body Mode) VESD 2 KV Storage Temperature TSTG 150 O C 245 O C Input Voltage. V IN to GND Lead Temperature (Soldering. 5sec) TL n Recommended Operating Conditions Parameter Symbol Rating Unit Supply Voltage 1 VIN 1.8 or 2.5 V Supply Voltage 2 VCNTL 3.3 V Output Current of V OUT Pin * *IOUT -2 to 2 A TJ -25 to 125 Junction Temperature O C *The symbol "+" means the VOUT sources current to load; the symbol "-" means the VOUT sinks current to GND n Thermal Characteristics Parameter Thermal Resistance* (Junction to Case) Thermal Resistance (Junction to Ambient) Package Die Attch SOP-8 Non-Conductive Epoxy SOP-8/PP Conductive Epoxy SOP-8 SOP-8/PP SOP-8 Internal Power Dissipation SOP-8/PP Rev. C.04 Non-Conductive Epoxy Conductive Epoxy Non-Conductive Epoxy Conductive Epoxy Symbol Maximum Unit 55 θJC 19 O C/W 120 θJA 84 1300 PD mW 1450 5 AME, Inc. Bus Termination Regulator AT9173 n Electrical Specifications Limits in standard typeface are for TA=25℃, unless otherwise specified: VIN=2.5V, VCNTL=3.3V, VREFEN =0.5V IN. Parameter Output Offset Voltage Load Regulation (DDR 1/2) Test Condition Symbol VOS VLOAD Min Typ Max Units I OUT=0A (Note 1) -20 0 20 mV I L=0~1.5A (Fig 4) -20 0 20 I L=0~-1.5A -20 0 20 1.6 2.5/1.8 4 2.5 3.3 6 mV Input Voltage Range (DDR 1/2) V CNTL KEEP VCNTL ≥ VIN on operation power on and power off Operating Current of VCNTL ICNTL No Load Current In Shutdown Mode ISHDN VREFEN < 0.2V, RL=180Ω (Fig 5) SOP-8 Current Limit ILIMIT Fig 6,7 2.1 A PSOP-8 Current Limit ILIMIT Fig 6,7 2.4 A TSD 3.3V VIN V 1.4 mA 25.6 µA Short Circuit Protection Over Temperature Protection Thermal Shutdown Temperature Thermal Shutdown Hysteresis ≤ VCNTL ≤ 5 V 125 O C Guaranteed by design 30 Note1: VOS offset is the voltage measurement defined as VOUT subtracted from VREFEN . 6 Rev. C.04 AME, Inc. AT9173 Bus Termination Regulator n Application Information VCNTL = 3.3V VIN = 1.8V RTT R1 REFEN 2N7002 EN R2 VCNTL VIN CSS AT9173 CIN CCNTL VOUT GND COUT RDUMMY R 1 = R2 = 100KO, RTT = 50O / 33O / 25O C OUT(MIN) = 10uF (Ceramic) + 1000uF under the worst case testing condition R DUMMY = 1KO as for VOUT discharge when V IN is not presented but VCNTL is presented C SS = 1uF, CIN = 470uF (Low ESR), C CNTL = 47uF n Application Circuit n General Regulator Typical application circuit is used as a regulator to provide termination voltage in double data rate (DDR) memory system. The regulator could source and sink up to 2A peak current. The output voltage will follow REFEN which generated by two external dividing resistors down from VIN or to the desired output voltage set externally by forcing a voltage level to REFEN pin. To add a shutdown function , connect a small transistor to REFEN pin. To perform shutdown function , put a logic high 5V signal to EN yield a low (0V) to REFEN pin thus force output voltage to zero voltage. The capacitor Css is used to softstart the output voltage since V OUT will follow REFEN. The AT9173 can be used as a general regulator. To get a desired output voltage, put a reference voltage to REFEN pin or dividing resistors down a input voltage source. To drive inside N-Channel MOSFET the VCNTL should be larger than VIN to get enough driving voltage. The minimum dropout voltage could be IOUT *0.1, where IOUT is the output current. Time constant for this circuit is Css*(R1//R2). The Css could also used as the bypass capacitor to filter out noise in REFEN pin. So carefully layout should put Css close to REFEN pin to maintain noise immunity. The C IN an C CNTL is used as power decoupling capacitor. COUT is composed of 10uF ceramic plus 1000uF electrolyte capacitors. The first one is to used as high frequency filter and the second one is used to reduce voltage drop during load regulating. Place a bypass capacitor as close as possible to VIN and VCNTL pin is necessary. A low ESR capacitor is recommended for this bypass capacitor. Use wide and short PCB traces to connect in between VIN power source VOUT to reduce PCB resistance thus to reduce undesired power dissipation. Rev. C.04 n Layout issue 7 AME, Inc. AT9173 Bus Termination Regulator n Thermal issue AT9173 has a internal thermal protection to protect the device at any overload conditions. For safety reason the operation junction temperature should not exceed 125 ℃. The dissipation of the device is PD = (V IN − V OUT ) xI OUT And also the maximum power dissipation is PD , MAX = (T J , MAX − T A ) / θ JA Where Tj,max is the maximum operation junction 125 degree C, Ta is the ambient temperature and the is θ JA the junction to ambient thermal resistance. The junction to ambient thermal resistance is 70 ℃ /W for exposed pad SOP-8 package. It can be dramatically reduced by placing a large area PCB trace under exposed pad to emit heat generated by the die attached to the exposed pad. 8 Rev. C.04 AME, Inc. AT9173 Bus Termination Regulator n Test Circuit Fig 4: Output Voltage Tolerance, △ VOUT Fig 5: Current in Shutdown Mode, ISHDN Rev. C.04 9 AME, Inc. AT9173 Bus Termination Regulator Figure 6: Current Limit for High Side, ICLHIGH Figure 7: Current Limit for Low Side, ICLLOW 10 Rev. C.04 AME, Inc. AT9173 Bus Termination Regulator n Typical Characteristics Rev. C.04 11 AME, Inc. Bus Termination Regulator AT9173 n Operation Waveforms DDR1 Load Transient Response VIN=2.5V, VCNTL=3.3V VREF is 1.25V supplied by a regulator COUT=1000uF/35V IOUT slew rate = +-0.25A/mS + 0 A→ + 1.5 A→ + 0 A + 0 A→ + 2 A → + 0 A + 0 A→ + 2.5 A→ + 0 A Ch1= IOUT ,Ch4 = VOUT Ch1= I OUT ,Ch4 = VOUT Ch1= I OUT ,Ch4 = VOUT Load Transient Response VIN=2.5V, VCNTL=3.3V VREF is 1.25V supplied by a regulator COUT=1000uF/35V IOUT slew rate = +-0.25A/mS - 0 A→ - 1.5 A→ - 0 A Ch1= IOUT ,Ch4 = VOUT 12 - 0 A → - 2 A→ - 0 A Ch1= I OUT ,Ch4 = VOUT - 0 A→ - 2.5 A→ - 0 A Ch1= IOUT ,Ch4 = VOUT Rev. C.04 AME, Inc. AT9173 Bus Termination Regulator n Operation Waveforms DDR2 Load Transient Response VIN=1.8V, VCNTL=3.3V VREF is 0.9V supplied by a regulator COUT=1000uF/35V IOUT slew rate = +-0.25A/mS + 0 A → + 1.5 A→ + 0 A Ch1= V OUT, Ch4= IOUT + 0 A→ + 2 A→ + 0 A Ch1= VOUT ,Ch4= IOUT Load Transient Response VIN=1.8V, VCNTL=3.3V VREF is 0.9V supplied by a regulator COUT=1000uF/35V IOUT slew rate = +-0.25A/mS - 0 A→ - 1.5 A→ - 0 A - 0 A → - 2 A→ - 0 A Ch1= VOUT , Ch4 = IOUT Ch1= VOUT , Ch4 = IOUT Rev. C.04 13 AME, Inc. Bus Termination Regulator AT9173 n Date Code Rule Marking Date Code Year A A A W W xxx0 A A A W W xxx1 A A A W W xxx2 A A A W W xxx3 A A A W W xxx4 A A A W W xxx5 A A A W W xxx6 A A A W W xxx7 A A A W W xxx8 A A A W W xxx9 n Tape and Reel Dimension SOP- 8 P W AME AME PIN 1 Carrier Tape, Number of Components Per Reel and Reel Size 14 Package Carrier Width (W) Pitch (P) Part Per Full Reel Reel Size SOP-8 12.0±0.1 mm 4.0±0.1 mm 2500pcs 330±1 mm Rev. C.04 AME, Inc. AT9173 Bus Termination Regulator n Tape and Reel Dimension SOP- 8/PP P W AME AME PIN 1 Carrier Tape, Number of Components Per Reel and Reel Size Rev. C.04 Package Carrier Width (W) Pitch (P) Part Per Full Reel Reel Size SOP-8/PP 12.0±0.1 mm 4.0±0.1 mm 2500pcs 330±1 mm 15 AME, Inc. Bus Termination Regulator AT9173 n Package Dimension SOP-8 Side View Top View SYMBOLS C E H L θ MIN MAX MIN MAX 1.35 1.75 0.05315 0.0689 A1 0.10 0.30 0.00394 0.01181 1.473 REF o 0.33 0.51 0.01299 0.02008 C 0.19 0.25 0.00748 0.00984 D 4.80 5.33 0.18898 0.20984 E 3.80 4.00 0.14961 0.15748 1.27 BSC 0.05000 BSC L 0.40 1.27 0.01575 0.05000 H 5.80 6.30 0.22835 0.24803 y - 0.10 θ A1 e A A2 7 (4X) 0.05799 REF B e Front View INCHES A A2 D MILLIMETERS 0 o 8 o 0 0.00394 o 8 o B SOP-8/PP Top View Side View D1 SYMBOLS θ E1 E E2 L1 C 1 Front View b 16 e A1 A A2 D MILLIMETERS INCHES MIN MAX MIN MAX A - 1.750 - 0.069 A1 0 0.150 0 0.006 A2 1.350 1.600 0.053 0.063 C 0.100 0.250 0.004 0.010 E 3.750 4.150 0.148 0.163 E1 5.700 6.300 0.224 0.248 L 0.300 0.900 0.012 0.035 b 0.310 0.510 0.012 0.020 D 4.720 5.120 0.186 0.202 e 1.270 BSC 0.05 BSC θ 0 E2 2.150 2.500 0.085 0.098 D1 2.150 3.400 0.085 0.134 o 8 o 0 o 8 o Rev. C.04 www.ame.com.tw E-Mail: [email protected] Life Support Policy: These products of AME, Inc. are not authorized for use as critical components in life-support devices or systems, without the express written approval of the president of AME, Inc. AME, Inc. reserves the right to make changes in the circuitry and specifications of its devices and advises its customers to obtain the latest version of relevant information. AME, Inc. , December 2007 Document: ATT-DS9173-C.04 Corporate Headquarter U.S.A (Subsidiary) AME, Inc. Analog Microelectronics, Inc. 2F, 302 Rui-Guang Road, Nei-Hu District Taipei 114, Taiwan. Tel: 886 2 2627-8687 Fax: 886 2 2659-2989 3100 De La Cruz Blvd., Suite 201 Santa Clara, CA. 95054-2046 Tel : (408) 988-2388 Fax: (408) 988-2489