AT9173 AME | Alldatasheet

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Technical content

AME, Inc. Rev. C.04 1 AT9173 Bus Termination Regulator n General Description n Features n Applications n Typical Application

  • DDRI/DDRII Memory Termination Supply
  • Active Termination Buses
  • Desktop PC,NoTebook,Server and workstation
  • Graphic Card
  • Set Top Box
  • Embedded System DDR _2.5V DDR_VTT 4.7uF 0.1uF 470uF 4 5 VIN GND REFEN VOUT VCNTL 1.25V/1.5A 100KO VCC_3.3V 100KO AT9173A-SOP 8 AT9173A SOP-8 VCNTL VCNTL VCNTL 470uF 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. The voltage output of the regulator can be used as a termination voltage for DDR SDRAM. Current limits in both sourcing and sinking mode, plus on-chip thermal shutdown make the circuit tolerant of the output fault conditions.
  • Support Both DDR I (1.25VTT) and DDR II (0.9VTT) Requirements
  • Capable of Sourcing and Sinking Current
  • Current-limiting Protection
  • Thermal Protection
  • Integrated Power MOSFETs
  • Generates Termination Voltages for SSTL-2
  • High Accuracy Output Voltage at Full-Load
  • Adjustable VOUT by External Resistors
  • Minimum External Components
  • Shutdown for Standby or Suspend Mode Operation with High-impedance Output

AME, Inc. 2 Rev. C.04 AT9173 Bus Termination Regulator n Function Block Diagram n Typical Application(Contd.) 4.7uF 0.1uF 470uFR1 100KO 100KO VIN GND REFEN VOUTL NC VCNTL NC NC GND_PAD AT9173E SOP-8/PP AT9173E-SOP 8 / PP 470uF DDR_VTT 1 .25V/2A5 VCC_3.3VDDR_2.5V VIN VCNTL Thermal Over Current Protection Circuit VOUT VCNTL REFEN GND Thermal Sensor

AME, Inc. Rev. C.04 3 AT9173 Bus Termination Regulator n Pin Configuration SOP- 8 Top View AT9173 1 32 4 5678 1 32 4 AT9173 5678 SOP- 8/PP Top View n Pin Description * By SOP-8/PP only AT9173A 1. IN 2. GND 3. REFEN 4. OUT 5. VCNTL 6. VCNTL 7. VCNTL 8. VCNTL AT9173E 1. IN 2. GND 3. REFEN 4. OUT 5. NC 6. VCNTL 7. NC 8. NC Pin name Pin Description IN Input voltage pin which supplies current to the VOUT pin. Connect this pin to a well- decoupled 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 VIN pin. GND 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. VOUT 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.

AME, Inc. 4 Rev. C.04 AT9173 Bus Termination Regulator n Ordering Information Part Number Marking Output Voltage Package Operating Temp. Range AT9173AG AT9173AG yyww* AB xxxxxxx##** ADJ SOP-8 AT9173EG AT9173EG yyww* AC xxxxxxx## ADJ SOP-8/PP -25oC to +85oC XXXXXXX represents the wafer lot number, ## represents the wafer number Note: * yy and ww represents the data code.

AME, Inc. Rev. C.04 5 AT9173 Bus Termination Regulator n Absolute Maximum Ratings n Thermal Characteristics n Recommended Operating Conditions *The symbol "+" means the VOUT sources current to load; the symbol "-" means the VOUT sinks current to GND Parameter Symbol Maximum Unit Input Voltage. VIN to GND VIN 6 V VCNTL to GND VCNTL 6 V ESD Rating (Human Body Mode) VESD 2 KV Storage Temperature TSTG 150 OC Lead Temperature (Soldering. 5sec) TL 245 OC Parameter Symbol Rating Unit Supply Voltage 1 VIN 1.8 or 2.5 V Supply Voltage 2 VCNTL 3.3 V Output Current of VOUT Pin * *IOUT -2 to 2 A Junction Temperature TJ -25 to 125 OC Parameter Package Die Attch Symbol Maximum Unit SOP-8 Non-Conductive Epoxy 55 SOP-8/PP Conductive Epoxy 19 SOP-8 Non-Conductive Epoxy 120 SOP-8/PP Conductive Epoxy 84 SOP-8 Non-Conductive Epoxy 1300 SOP-8/PP Conductive Epoxy 1450 OC/W mWPD Internal Power Dissipation Thermal Resistance* (Junction to Case) θ JC Thermal Resistance (Junction to Ambient) θ JA

AME, Inc. 6 Rev. C.04 AT9173 Bus Termination Regulator n Electrical Specifications Note1: VOS offset is the voltage measurement defined as VOUT subtracted from VREFEN. Limits in standard typeface are for TA=25 , unless otherwise specified:℃ VIN=2.5V, VCNTL=3.3V, VREFEN=0.5VIN. Parameter Symbol Min Typ Max Units Output Offset Voltage VOS -20 0 20 mV -20 0 20 -20 0 20 VIN 1.6 2.5/1.8 4 VCNTL 2.5 3.3 6 Operating Current of VCNTL ICNTL 1.4 mA Current In Shutdown Mode ISHDN 25.6 µA SOP-8 Current Limit ILIMIT 2.1 A PSOP-8 Current Limit ILIMIT 2.4 A Thermal Shutdown Temperature TSD 125 Thermal Shutdown Hysteresis 30Guaranteed by design OC V No Load Over Temperature Protection 3.3V VCNTL 5 V Test Condition IL=0~1.5A (Fig 4) IOUT=0A (Note 1) mV Short Circuit Protection Fig 6,7 Fig 6,7 VREFEN < 0.2V, RL=180Ω (Fig 5) IL=0~-1.5A Load Regulation (DDR 1/2) VLOAD Input Voltage Range (DDR 1/2) KEEP VCNTL VIN on operation power on and power off

AME, Inc. Rev. C.04 7 AT9173 Bus Termination Regulator n Application Information n Application Circuit n General Regulator n Layout issue CSS = 1uF, CIN = 470uF (Low ESR), CCNTL = 47uF R1 = R2 = 100KO, RTT = 50O / 33O / 25O COUT(MIN) = 10uF (Ceramic) + 1000uF under the worst case testing condition RDUMMY = 1KO as for VOUT discharge when VIN is not presented but VCNTL is presented 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. 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 VOUT will follow REFEN. 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 CIN an CCNTL 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. 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. VIN VCNTL VOUT GND REFEN AT9173 CIN CCNTL COUT RDUMMY CSSR2 VCNTL = 3.3V VIN = 1.8V EN 2N7002 RTT

AME, Inc. 8 Rev. C.04 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 And also the maximum power dissipation is Where Tj,max is the maximum operation junction 125 degree C, Ta is the ambient temperature and the is 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. JAAMAXJMAXD TTP q/)( ,, −= OUTOUTIND xIVVP )( −= JAq

AME, Inc. Rev. C.04 9 AT9173 Bus Termination Regulator n Test Circuit Fig 4: Output Voltage Tolerance, V△ OUT Fig 5: Current in Shutdown Mode, I SHDN

AME, Inc. Rev. C.04 11 AT9173 Bus Termination Regulator n Typical Characteristics

AME, Inc. 12 Rev. C.04 AT9173 Bus Termination Regulator 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 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= IOUT , Ch4 = VOUT Ch1= IOUT , Ch4 = VOUT - 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= IOUT , Ch4 = VOUT Ch1= IOUT , Ch4 = VOUT

AME, Inc. Rev. C.04 13 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 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 - 0 A → - 1.5 A → - 0 A - 0 A → - 2 A → - 0 A Ch1= VOUT , Ch4 = IOUT Ch1= VOUT , Ch4 = IOUT

AME, Inc. 14 Rev. C.04 AT9173 Bus Termination Regulator n Date Code Rule n Tape and Reel Dimension SOP- 8 Carrier Tape, Number of Components Per Reel and Reel Size 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 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 Marking Date Code PIN 1 W P AME AME

AME, Inc. Rev. C.04 15 AT9173 Bus Termination Regulator n Tape and Reel Dimension Carrier Tape, Number of Components Per Reel and Reel Size SOP- 8/PP 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 PIN 1 W P AME AME

AME, Inc. 16 Rev. C.04 AT9173 Bus Termination Regulator n Package Dimension SOP-8 SOP-8/PP MIN MAX MIN MAX A 1.35 1.75 0.05315 0.0689 A1 0.10 0.30 0.00394 0.01181 B 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 e L 0.40 1.27 0.01575 0.05000 H 5.80 6.30 0.22835 0.24803 y - 0.10 - 0.00394 q 0o 8o 0o 8o 1.473 REF 0.05799 REF 1.27 BSC 0.05000 BSC SYMBOLS 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 q 0o 8o 0o 8o E2 2.150 2.500 0.085 0.098 D1 2.150 3.400 0.085 0.134 1.270 BSC 0.05 BSC SYMBOLS MILLIMETERS INCHES 7o(4X) Top View Side View Front View D E A A2A1e B H θ L C EE2 Top View Side View b e D A Front View C θ

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 3100 De La Cruz Blvd., Suite 201 Taipei 114, Taiwan. Santa Clara, CA. 95054-2046 Tel: 886 2 2627-8687 Tel : (408) 988-2388 Fax: 886 2 2659-2989 Fax: (408) 988-2489 www.ame.com.tw E-Mail: sales@ame.com.tw