PTH08T250WAST

PTH08T255W www.ti.com ........................................................................................................................................................................................... SLTS290 – NOVEMBER 2008 40-A, 8-V to 14-V INPUT, 3-V to 5.25-V OUTPUT, NON-ISOLATED, ADJUSTABLE POWER MODULE FEATURES 1 • • • • • • 2 • • • • • • • • • Up to 40-A Output Current 8-V to 14-V Input Voltage Wide-Output Voltage Adjust (3.0 V to 5.25 V) ±1.5% Total Output Voltage Variation Efficiencies up to 96% Output Overcurrent Protection (Nonlatching, Auto-Reset) Operating Temperature: –40°C to 85°C Safety Agency Approvals: (Pending) – UL/IEC/CSA-C22.2 60950-1 Prebias Startup On/Off Inhibit Differential Output Voltage Remote Sense Adjustable Undervoltage Lockout Auto-Track™ Sequencing Multi-Phase, Switch-Mode Topology TurboTrans™ Technology • • • Designed to meet Ultra-Fast Transient Requirements up to 300 A/µs SmartSync Technology Parallel Operation APPLICATIONS • • • Complex Multi-Voltage Systems Servers Workstations DESCRIPTION The PTH08T255W is a high-performance 40-A rated, non-isolated power module. This module represents the 2nd generation of the popular PTH series power modules with a reduced footprint and improved features. Operating from an input voltage range of 8 V to 14 V, the PTH08T255W requires a single resistor to set the output voltage to any value over the range, 3.0 V to 5.25 V. The wide input voltage range makes the PTH08T255W particularly suitable for advanced computing and server applications that utilize a loosely regulated 9.6-V to 12-V intermediate distribution bus. The module incorporates a comprehensive list of features. Output overcurrent and over-temperature shutdown protects against most load faults. A differential remote sense ensures tight load regulation. An adjustable under-voltage lockout allows the turn-on voltage threshold to be customized. Auto-Track™ sequencing is a popular feature that greatly simplifies the simultaneous power-up and power-down of multiple modules in a power system. Additionally, the capability to current share between multiple PTH08T255W modules allows for load currents greater than 40A on a single rail. The PTH08T255W includes new patented technologies, TurboTrans™ and SmartSync. The TurboTrans feature optimizes the transient response of the regulator while simultaneously reducing the quantity of external output capacitors required to meet a target voltage deviation specification. Additionally, for a target output capacitor bank, TurboTrans can be used to significantly improve the regulators transient response by reducing the peak voltage deviation. SmartSync allows for switching frequency synchronization of multiple modules, thus simplifying EMI noise suppression tasks and reducing input capacitor RMS current requirements. The module uses double-sided surface mount construction to provide a low profile and compact footprint. Package options include both through-hole and surface mount configurations that are lead (Pb) - free and RoHS compatible. 1 2 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. Auto-Track, TMS320, TurboTrans are trademarks of Texas Instruments. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright © 2008, Texas Instruments Incorporated PTH08T255W SLTS290 – NOVEMBER 2008 ........................................................................................................................................................................................... www.ti.com These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. STANDARD APPLICATION [A] 20 VI 2 Track 6 VI 7 VI 3 5 RTT 1% 0.05 W (Optional) +Sense 19 Share Comp CLKIO TT +Sense 17 14 VI VO 10 15 VI VO 11 PTH08T255W Inhibit 21 Inhibit/UVLO -Sense 16 22 SmartSync + Config 1 CI 1000 mF (Required) GND GND 8 9 12 13 VO AGND VOAdj 4 18 RSET 1%, 0.05 W (Required) + C O 1000 mF (Required) L O A D -Sense GND UDG-08144 A. When using the AutoTrack feature with the PTH08T225W, a 100-kΩ pull-up resistor to VI is required. If the AutoTrack feature is not used, this pin must be directly connected to VI. 2 Copyright © 2008, Texas Instruments Incorporated Product Folder Link(s): PTH08T255W PTH08T255W www.ti.com ........................................................................................................................................................................................... SLTS290 – NOVEMBER 2008 ORDERING INFORMATION For the most current package and ordering information, see the Package Option Addendum at the end of this datasheet, or see the TI website at www.ti.com. DATASHEET TABLE OF CONTENTS DATASHEET SECTION PAGE NUMBER ENVIRONMENTAL AND ABSOLUTE MAXIMUM RATINGS 3 ELECTRICAL CHARACTERISTICS TABLE (PTH08T255W) 4 TERMINAL FUNCTIONS 6 TYPICAL CHARACTERISTICS (VI = 12V) 7 ADJUSTING THE OUTPUT VOLTAGE 8 INPUT & OUTPUT CAPACITOR RECOMMENDATIONS 9 TURBOTRANS™ INFORMATION 13 SOFT-START POWER-UP 17 REMOTE SENSE 17 OUTPUT INHIBIT 18 OVERCURRENT PROTECTION 18 OVER-TEMPERATURE PROTECTION 18 SYCHRONIZATION (SMARTSYNC) 19 AUTO-TRACK SEQUENCING 20 UNDERVOLTAGE LOCKOUT (UVLO) 23 CURRENT SHARING 24 CURRENT SHARING SOA GRAPHS 26 CURRENT SHARING LAYOUT 27 PREBIAS START-UP 27 TAPE & REEL AND SHIPPING TRAY DRAWING 29 ENVIRONMENTAL AND ABSOLUTE MAXIMUM RATINGS (Voltages are with respect to GND) UNIT Vtrack Track pin voltage –0.3 to VI + 0.3 TA Operating temperature range Over VI range Twave Wave soldering temperature Surface temperature of module body or pins (5 seconds maximum) Treflow Solder reflow temperature Surface temperature of module body or pins Tstg Storage temperature Storage temperature of module removed from shipping package Tpkg Packaging temperature Shipping Tray or Tape and Reel storage or bake temperature 45 Mechanical shock Per Mil-STD-883D, Method 2002.3 1 msec, 1/2 sine, mounted AD suffix 500 AS and AZ suffix 125 Mechanical vibration Mil-STD-883D, Method 2007.2 20-2000 Hz Weight Flammability (1) V –40 to 85 AD suffix 260 AS suffix 235 (1) AZ suffix 260 (1) °C –55 to 125 G 20 16.7 grams Meets UL94V-O During reflow of surface mount package version do not elevate peak temperature of the module, pins or internal components above the stated maximum. 3 Copyright © 2008, Texas Instruments Incorporated Product Folder Link(s): PTH08T255W PTH08T255W SLTS290 – NOVEMBER 2008 ........................................................................................................................................................................................... www.ti.com ELECTRICAL CHARACTERISTICS PTH08T255W TA = 25°C, VI = 12 V, VO = 3.3 V, CI = 1000 µF, CO = 1000 µF, and IO = IO max (unless otherwise stated) PARAMETER TEST CONDITIONS PTH08T255W MIN TYP UNIT MAX 25°C, natural convection 0 40 60°C, 200 LFM 0 40 IO Output current Over VO range VI Input voltage range Over IO and VO range 8.0 14 VOADJ Output voltage adjust range Over IO range 3.0 5.25 Set-point voltage tolerance VO η ILIM ±0.5 –40°C < TA < 85°C ±0.3 %Vo Over VI range ±5 mV Load regulation Over IO range ±5 Total output variation Includes set-point, line, load, –40°C ≤ TA ≤ 85°C Efficiency IO = 30 A VO Ripple (peak-to-peak) 20-MHz bandwidth 20 Overcurrent threshold Reset, followed by auto-recovery 80 A Recovery time 200 µs VO over/undershoot 135 mV Recovery time 400 µs 35 mV Transient response 2.5 A/µs load step 50 to 100% IOmax ΔVtrTT 95% RSET = 34.5 kΩ, VO = 3.3 V 94% w/o TurboTrans CO= 1000 µF, TypeC w/ TurboTrans CO= 5000 µF, TypeC RTT = short VO over/undershoot Pin to GND dVtrack/dt Track slew rate capability CO ≤ CO (max) UVLOADJ VI increasing, RUVLO = OPEN Adjustable Under-voltage lockout VI decreasing, RUVLO = OPEN (pin 21) Hysteresis 7.2 Inhibit (pin 21) to GND, Track (pin 20) open fs Switching frequency Over VI and IO ranges, SmartSync (pin 22) to GND Open (3) -0.2 tSYNC CI (1) (2) (3) (4) (5) 0.6 240 SYNC High-Level Input Voltage µA 35 mA (4) (4) (4) 5.5 SYNC Low-Level Input Voltage 0.8 200 Nonceramic External input capacitance kHz 400 2.0 SYNC Minimum Pulse Width Ceramic 1000 V -125 600 Synchronization frequency applied to pin 22 Synchronization (SYNC) control (pin 22) V 0.5 Input low current (IIL ), Pin 21 to GND Input standby current µA V/ms 8.0 6.7 Input low voltage (VIL) Iin %Vo mVPP 1 Input high voltage (VIH) fSYNC (1) –130 (2) Track input current (pin 20) Inhibit control (pin 21) mV ±1.5 RSET = 1.36 kΩ, VO = 5.0 V IIL VSYNCL V %Vo Line regulaltion ΔVtr VSYNCH (1) V Temperature variation ttr ttrTT ±1 A kHz V V nSec (5) 22 µF The set-point voltage tolerance is affected by the tolerance and stability of RSET. The stated limit is unconditionally met if RSET has a tolerance of 1% with 100 ppm/C or better temperature stability. A low-leakage ( 4700 µF). To ensure stability, a minimum amount of output capacitance is required for a given RTT resistor value. The value of RTT must be calculated using the minimum required output capacitance determined from Figure 8. 15 Copyright © 2008, Texas Instruments Incorporated Product Folder Link(s): PTH08T255W PTH08T255W SLTS290 – NOVEMBER 2008 ........................................................................................................................................................................................... www.ti.com TurboTrans AutoTrack RTT 20 kW TurboTrans +Sense VI +Sense VI VO VO PTH08T255W Inhibit/UVLO + -Sense CO 2000 mF Type B + SmartSync Config CI 1000 mF (Required) CI2 22 mF GND AGND VOAdj RSET L O A D -Sense GND GND UDG-08146 Figure 9. Typical TurboTrans™ Application 16 Copyright © 2008, Texas Instruments Incorporated Product Folder Link(s): PTH08T255W PTH08T255W www.ti.com ........................................................................................................................................................................................... SLTS290 – NOVEMBER 2008 Soft-Start Power Up The Auto-Track feature allows the power-up of multiple PTH/PTV modules to be directly controlled from the Track pin. However in a stand-alone configuration, or when the Auto-Track feature is not being used, the Track pin should be directly connected to the input voltage, VI (see Figure 10). VI (5 V/div) 20 Track VI 6 VI 7 VI PTH08T255W 14 VI + 15 VI CI GND GND GND GND 8 9 12 13 VO (2 V/div) GND II (5 A/div) UDG-08147 t – Time – 10 ms/div Figure 10. Defeating the Auto-Track Function Figure 11. Power-Up Waveform When the Track pin is connected to the input voltage the Auto-Track function is permanently disengaged. This allows the module to power up entirely under the control of its internal soft-start circuitry. When power up is under soft-start control, the output voltage rises to the set-point at a quicker and more linear rate. From the moment a valid input voltage is applied, the soft-start control introduces a short time delay (typically 10 ms–15 ms) before allowing the output voltage to rise. The output then progressively rises to the module’s setpoint voltage. Figure 11 shows the soft-start power-up characteristic of the PTH08T255W operating from a 12-V input bus and configured for a 5.0-V output. The waveforms were measured with a 25-A constant current load and the Auto-Track feature disabled. The initial rise in input current when the input voltage first starts to rise is the charge current drawn by the input capacitors. Power-up is complete within 30 ms. Differential Output Voltage Remote Sense Differential remote sense improves the load regulation performance of the module by allowing it to compensate for any IR voltage drop between its output and the load in either the positive or return path. An IR drop is caused by the output current flowing through the small amount of pin and trace resistance. With the sense pins connected, the difference between the voltage measured directly between the VO and GND pins, and that measured at the Sense pins, is the amount of IR drop being compensated by the regulator. This should be limited to a maximum of 0.3V. If the remote sense feature is not used at the load, connect +Sense (pin 17) to VO (pin11) and connect –Sense (pin 16) to the module GND (pin 13). The remote sense feature is not designed to compensate for the forward drop of nonlinear or frequency dependent components that may be placed in series with the converter output. Examples include OR-ing diodes, filter inductors, ferrite beads, and fuses. When these components are enclosed by the remote sense connection they are effectively placed inside the regulation control loop, which can adversely affect the stability of the regulator. 17 Copyright © 2008, Texas Instruments Incorporated Product Folder Link(s): PTH08T255W PTH08T255W SLTS290 – NOVEMBER 2008 ........................................................................................................................................................................................... www.ti.com On/Off Inhibit For applications requiring output voltage on/off control, the PTH08T255W incorporates an Inhibit control pin. The inhibit feature can be used wherever there is a requirement for the output voltage from the regulator to be turned off. The power modules function normally when the Inhibit pin is left open-circuit, providing a regulated output whenever a valid source voltage is connected to VI with respect to GND. Figure 12 shows the typical application of the inhibit function. Note the discrete transistor (Q1). The Inhibit input has its own internal pull-up. An external pull-up resistor should never be used with the inhibit pin. The input is not compatible with TTL logic devices. An open-collector (or open-drain) discrete transistor is recommended for control. When Q1 it turned on, low voltage is applied to the Inhibit control pin and disables the output of the module. If Q1 is then turned off, the module executes a soft-start power-up sequence. A regulated output voltage is produced within 20 ms. Figure 13 shows the typical rise in both the output voltage and input current, following the turn-off of Q1. The turn off of Q1 corresponds to the rise in the waveform, VINH. The waveforms were measured with a 25-A constant current load. VI 6 VI 7 VI VO (2 V/div) PTH08T255W 14 VI + 15 VI CI 21 Inhibit/UVLO GND GND GND GND 1=Inhibit 8 9 12 13 Q1 BSS 138 II (5 A/div) GND VINH (2 V/div) UDG-08148 t – Time – 10 ms/div Figure 12. On/Off Inhibit Control Circuit Figure 13. Power-Up Response from Inhibit Control Overcurrent Protection For protection against load faults, all modules incorporate output overcurrent protection. Applying a load that exceeds the regulator's overcurrent threshold causes the regulated output to shut down. Following shutdown, the module periodically attempts to recover by initiating a soft-start power-up. This is described as a hiccup mode of operation, whereby the module continues in a cycle of successive shutdown and power up until the load fault is removed. During this period, the average current flowing into the fault is significantly reduced. Once the fault is removed, the module automatically recovers and returns to normal operation. Overtemperature Protection (OTP) A thermal shutdown mechanism protects the module’s internal circuitry against excessively high temperatures. A rise in the internal temperature may be the result of a drop in airflow, or a high ambient temperature. If the internal temperature exceeds the OTP threshold, the module’s Inhibit control is internally pulled low. This turns the output off. The output voltage drops as the external output capacitors are discharged by the load circuit. The recovery is automatic, and begins with a soft-start power up. It occurs when the sensed temperature decreases by about 10°C below the trip point. 18 Copyright © 2008, Texas Instruments Incorporated Product Folder Link(s): PTH08T255W PTH08T255W www.ti.com ........................................................................................................................................................................................... SLTS290 – NOVEMBER 2008 The overtemperature protection is a last resort mechanism to prevent thermal stress to the regulator. Operation at or close to the thermal shutdown temperature is not recommended and reduces the long-term reliability of the module. Always operate the regulator within the specified safe operating area (SOA) limits for the worst-case conditions of ambient temperature and airflow. Smart Sync Smart Sync is a feature that allows multiple power modules to be synchronized to a common frequency. When not used, this pin must be connect to GND. Driving the Smart Sync pins with an external oscillator set to the desired frequency, synchronizes all connected modules to the selected frequency. The synchronization frequency can be higher or lower than the nominal switching frequency of the modules within the range of 240 kHz to 400 kHz. Synchronizing modules powered from the same bus eliminates beat frequencies reflected back to the input supply, and also reduces EMI filtering requirements. Eliminating the low beat frequencies (usually