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PTH04T240FAS

PTH04T240FAS

  • 厂商:

    BURR-BROWN(德州仪器)

  • 封装:

    DIPMODULE11

  • 描述:

    MODULE PIP 10A 2.2/5.5V 11SMD

  • 数据手册
  • 价格&库存
PTH04T240FAS 数据手册
PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 10-A, 2.2-V to 5.5-V INPUT, NON-ISOLATED POWER MODULE FOR 3-GHz DSP SYSTEMS FEATURES 1 • • • • • • 2 • • • • • • • • Up to 10-A Output Current 2.2-V to 5.5-V Input Voltage Wide-Output Voltage Adjust (0.69 V to 2.0 V) ±1.5% Total Output Voltage Variation Efficiencies up to 94% Output Overcurrent Protection (Nonlatching, Auto-Reset) Operating Temperature: –40°C to 85°C Safety Agency Approvals: – UL/IEC/CSA-C22.2 60950-1 Prebias Startup On/Off Inhibit Differential Output Voltage Remote Sense Adjustable Undervoltage Lockout Auto-Track™ Sequencing SmartSync Technology • • • TurboTrans™ Technology Designed to meet Ultra-Fast Transient Requirements for 3-GHz DSP Systems 15 mV Output Voltage Deviation (CO = 2000 µF, ΔI = 3 A) APPLICATIONS • Wireless Infrastructure Base Stations DESCRIPTION The PTH04T240F is a high-performance 10-A rated, non-isolated power module designed to meet ultra-fast transient requirements for 3-GHz DSP systems like Texas Instruments' TMS320TCI6488. This module is an addition to the 2nd generation of the popular PTH series power modules which include a reduced footprint and additional features. Operating from an input voltage range of 2.2 V to 5.5 V, the PTH04T240F requires a single resistor to set the output voltage to any value over the range, 0.69 V to 2.0 V. The output voltage range makes the PTH04T240F particularly suitable for the 3-GHz DSP's core voltage requirements. The module incorporates a comprehensive list of features. Output over-current 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. The PTH04T240F includes new patent pending 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. TurboTrans allows the PTH04T240F to meet the tight transient voltage tolerances required by 3-GHz DSPs with minimal output capacitance. 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, TurboTrans, TMS320 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 © 2008–2009, Texas Instruments Incorporated PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... 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. PTH04T240F SmartSync Track TurboTrans™ 10 VI Track 2 1 SYNC TT +Sense VI 11 INH/UVLO + RUVLO 1% 0.05 W (Optional) CI 220 mF (Required) CI2 22 mF (Optional) 6 +Sense 5 PTH04T240F Inhibit RTT 1% 0.05W (Required) 9 VO VO -Sense GND GND VOAdj 3 4 8 7 RSET[A] 1% 0.05 W (Required) L O A D + CO 1000 mF (Required) GND -Sense GND UDG-08158 A. 2 `RSET required to set the output voltage to a value higher than 0.69 V. See Electrical Characteristics table. Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 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 (PTH04T240F) 4 TERMINAL FUNCTIONS 6 TYPICAL CHARACTERISTICS (VI = 5V) 7 TYPICAL CHARACTERISTICS (VI = 3.3V) 8 ADJUSTING THE OUTPUT VOLTAGE 9 INPUT & OUTPUT CAPACITOR RECOMMENDATIONS 11 TURBOTRANS™ INFORMATION 15 UNDERVOLTAGE LOCKOUT (UVLO) 19 SOFT-START POWER-UP 20 OUTPUT ON/OFF INHIBIT 21 SYCHRONIZATION (SMARTSYNC) 22 OVER-CURRENT PROTECTION 23 OVER-TEMPERATURE PROTECTION 23 REMOTE SENSE 23 AUTO-TRACK SEQUENCING 24 PREBIAS START-UP 27 TAPE & REEL DRAWING 28 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 for 5 seconds maximum. Treflow Solder reflow temperature Surface temperature of module body or pins Tstg Storage temperature (2) suffix AS suffix AZ 260 235 (1) 260 (1) Mechanical shock Per Mil-STD-883D, Method 2002.3 1 msec, 1/2 sine, mounted 500 Mechanical vibration Mil-STD-883D, Method 2007.2 20-2000 Hz suffix AD 20 suffix AS & AZ 15 Flammability (1) suffix AD –55 to 125 Weight V –40 to 85 °C (2) 3.8 G 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. The shipping tray or tape and reel cannot be used to bake parts at temperatures higher than 65°C. Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 3 PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... www.ti.com ELECTRICAL CHARACTERISTICS PTH04T240F TA = 25°C, VI = 5 V, VO = 1.0 V, CI = 220 µF, CO = 1000 µF, and IO = IO max (unless otherwise stated) PARAMETER TEST CONDITIONS PTH04T240F MIN IO Output current Over VO range VI Input voltage range Over IO range VOADJ Output voltage adjust range Over IO range 25°C, natural convection 0.69 ≤ VO ≤ 1.7 1.7 < VO ≤ 2.0 η 0 10 5.5 VO+0.5 (1) 5.5 0.69 ±0.3 %Vo ±3 mV Load regulation Over IO range ±2 Total output variation Includes set-point, line, load, –40°C ≤ TA ≤ 85°C IO = 10 A RSET = 2.83 kΩ, VO = 2.0 V 91% RSET = 4.78 kΩ, VO = 1.8 V 90% RSET = 7.09 kΩ, VO = 1.5 V 88% RSET = 12.1 kΩ, VO = 1.2 V 87% RSET = 20.8 kΩ, VO = 1.0 V 85% RSET = 689 kΩ, VO = 0.7 V 80% 20 Reset, followed by auto-recovery 20 A 200 µs VO over/undershoot 28 mV Recovery time 300 µs VO over/undershoot 15 mV 2.5 A/µs load step 0.5 A to 3.5 A VO = 0.9 V dVtrack/dt Track slew rate capability CO ≤ CO (max) Adjustable Under-voltage lockout (pin 11) CO = 1000 µF, TypeB RTT = open CO = 2000 µF, TypeB, RTT = 23.7 kΩ Recovery time 1 VI increasing, RUVLO = OPEN 1.95 VI decreasing, RUVLO = OPEN 1.5 Hysteresis, RUVLO = OPEN 0.5 Inhibit control (pin 11) -0.2 Input low current (IIL), Pin 11 to GND Input standby current Inhibit (pin 11) to GND, Track (pin 10) open fs Switching frequency Over VI and IO ranges, SmartSync (pin 1) to GND fSYNC Synchronization (SYNC) frequency VSYNCH SYNC High-Level Input Voltage VSYNCL SYNC Low-Level Input Voltage tSYNC SYNC Minimum Pulse Width CI External input capacitance 4 0.8 V µA 5 mA 300 kHz 240 400 kHz 2 5.5 V 200 Ceramic V/ms 235 0.8 Nonceramic µA V Open (4) Input low voltage (VIL) Iin mVPP –130 (3) Input high voltage (VIH) (5) %Vo Overcurrent threshold Pin to GND (4) (2) 20-MHz bandwidth Track input current (pin 10) (3) mV ±1.5 VO Ripple (peak-to-peak) IIL (1) (2) V %Vo Over VI range ΔVtrTT UVLOADJ (2) –40°C < TA < 85°C Transient response ttrTT ±1 V Line regulaltion ttr ΔVtr 2.0 ±0.5 A Temperature variation Efficiency ILIM UNIT MAX 2.2 Set-point voltage tolerance VO TYP 220 V ns (5) 22 (5) µF The minimum input voltage is 2.2 V or (VO + 0.5) V, whichever is greater. 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 ( 5000µF). To ensure stability, the value of RTT must be calculated using the minimum required output capacitance determined from the capacitor transient response charts above. Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 17 PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... www.ti.com TurboTrans 10 9 Auto Track 1 VI TurboTrans +Sense Smart Sync 2 VI PTH04T240F 11 Inhibit/ Prog UVLO 3 CI 220 mF Required) 4 6 +Sense 5 VO VO -Sense GND + RTT 18.7 kW 7 VOAdj L O A D + 8 RSET 1% 0.05 W CO 2200 mF -Sense GND GND UDG-08160 Figure 14. Typical TurboTrans™ Application PTH04T240F CO = 2200 mF Without TurboTrans (20 mV/div) With TurboTrans (20 mV/div) 2.5 A/ms 3 A Load Step T - Time - 200 ms/div Figure 15. Typical TurboTrans Waveforms 18 Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 UNDERVOLTAGE LOCKOUT (UVLO) The PTH04T240F power modules incorporate an input undervoltage lockout (UVLO). The UVLO feature prevents the operation of the module until there is sufficient input voltage to produce a valid output voltage. This enables the module to provide a clean, monotonic powerup for the load circuit, and also limits the magnitude of current drawn from the regulator input source during the power-up sequence. The UVLO characteristic is defined by the ON threshold (VTHD) voltage. Below the ON threshold, the Inhibit control is overridden, and the module does not produce an output. The hysteresis voltage, which is the difference between the ON and OFF threshold voltages, is set at 500 mV. The hysteresis prevents start-up oscillations, which can occur if the input voltage droops slightly when the module begins drawing current from the input source. The UVLO feature of the PTH04T240F module allows for limited adjustment of the ON threshold voltage. The adjustment is made via the Inhbit/UVLO Prog control pin (pin 11) using a single resistor (see Figure 16). When pin 11 is left open circuit, the ON threshold voltage is internally set to the 1.95-V default value. The ON threshold might need to be raised if the module is powered from a tightly regulated 5-V bus. Adjusting the threshold prevents the module from operating if the input bus fails to completely rise to its specified regulation voltage. Equation 4 determines the value of RUVLO required to adjust VTHD to a new value. The default value is 1.95 V, and it may be adjusted to a higher value only. 68.54 * V THD R UVLO + kW V THD * 2.07 (4) Table 6 lists the standard resistor values for RUVLO for different values of the on-threshold (VTHD) voltage. Table 6. Standard RUVLO values for Various VTHD values VTHD(V) 2.5 3.0 3.5 4.0 4.5 RUVLO (kΩ) 154 71.5 53.6 33.2 26.7 PTH04T240F VI 2 VI 11 + CI GND Inhibit/ UVLO Prog GND 3 4 RUVLO UDG-08161 Figure 16. Undervoltage Lockout Adjustment Resistor Placement Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 19 PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... www.ti.com 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 17). 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 5 ms–15 ms) before allowing the output voltage to rise. The output then progressively rises to the module’s setpoint voltage. Figure 18 shows the soft-start power-up characteristic of the PTH04T240F operating from a 5-V input bus and configured for a 1.8-V output. The waveforms were measured with a 10-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. 10 VI (2 V/div) Track PTH04T240F VI VO (500 mV/div) 2 VI GND + CI 3 II (1 A/div) 4 GND UDG-08162 T - Time - 4 ms/div Figure 17. Defeating the Auto-Track Function 20 Submit Documentation Feedback Figure 18. Power-Up Waveform Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 On/Off Inhibit For applications requiring output voltage on/off control, the PTH04T240F 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 19 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. Turning Q1 on applies a low voltage 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 40 ms. Figure 20 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 10-A constant current load. VI PTH04T240F 2 VI VO (500 mV/div) 11 + CI 1=Inhibit Inhibit/ UVLO Prog GND 3 II (1 A/div) 4 VI (2 V/div) GND UDG-08163 T - Time - 4 ms/div Figure 19. On/Off Inhibit Control Circuit Figure 20. Power-Up Response from Inhibit Control Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 21 PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... www.ti.com Smart Sync Smart Sync is a feature that allows multiple power modules to be synchronized to a common frequency. 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 (see Electrical Specifications table for synchronization limits). 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 < 10 kHz) allows the EMI filter to be designed to attenuate only the synchronization frequency. Power modules can also be synchronized out of phase to minimize source current loading and minimize input capacitance requirements. Figure 21 shows a standard circuit with two modules syncronized 180° out of phase using a D flip-flop. Track 0° VI = 5 V TT SYNC +Sense VI VO1 PTH08T220W SN74LVC2G74 + VCC fCLK = 2 x fMODULE CLR PRE CLK Q D Q GND VO Inhibit/ UVLO -Sense GND CI1 330 mF + VOAdj CO1 220 mF RSET1 GND 180° Track Sync TT +Sense VI VO2 PTH04T240F Inhibit/ UVLO + VO -Sense GND VoAdj CI2 220 mF + CO2 1000 mF RSET2 GND UDG-08164 Figure 21. Smart Sync Schematic 22 Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 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. 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. 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. Connecting the +Sense (pin 6) to the positive load terminal improves the load regulation at the connection point. For optimal behavior the –Sense (pin 7) must be connected to GND (pin 4) close to the module (within 10 cm). If the remote sense feature is not used at the load, connect the +Sense pin to VO (pin5) and connect the –Sense pin to the module GND (pin 4). 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. Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 23 PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... www.ti.com Auto-Track™ Function The Auto-Track function is unique to the PTH/PTV family, and is available with all POLA products. Auto-Track was designed to simplify the amount of circuitry required to make the output voltage from each module power up and power down in sequence. The sequencing of two or more supply voltages during power up is a common requirement for complex mixed-signal applications that use dual-voltage VLSI ICs such as the TMS320™ DSP family, microprocessors, and ASICs. How Auto-Track™ Works Auto-Track works by forcing the module output voltage to follow a voltage presented at the Track control pin (1). This control range is limited to between 0 V and the module set-point voltage. Once the track-pin voltage is raised above the set-point voltage, the module output remains at its set-point (2). As an example, if the Track pin of a 2.5-V regulator is at 1 V, the regulated output is 1 V. If the voltage at the Track pin rises to 3 V, the regulated output does not go higher than 2.5 V. When under Auto-Track control, the regulated output from the module follows the voltage at its Track pin on a volt-for-volt basis. By connecting the Track pin of a number of these modules together, the output voltages follow a common signal during power up and power down. The control signal can be an externally generated master ramp waveform, or the output voltage from another power supply circuit (3). For convenience, the Track input incorporates an internal RC-charge circuit. This operates off the module input voltage to produce a suitable rising waveform at power up. Typical Application The basic implementation of Auto-Track allows for simultaneous voltage sequencing of a number of Auto-Track compliant modules. Connecting the Track inputs of two or more modules forces their track input to follow the same collective RC-ramp waveform, and allows their power-up sequence to be coordinated from a common Track control signal. This can be an open-collector (or open-drain) device, such as a power-up reset voltage supervisor IC. See U3 in Figure 22. To coordinate a power-up sequence, the Track control must first be pulled to ground potential. This should be done at or before input power is applied to the modules. The ground signal should be maintained for at least 20 ms after input power has been applied. This brief period gives the modules time to complete their internal soft-start initialization (4), enabling them to produce an output voltage. A low-cost supply voltage supervisor IC, that includes a built-in time delay, is an ideal component for automatically controlling the Track inputs at power up. Figure 22 shows how a TPS3808 supply voltage supervisor IC (U3) can be used to coordinate the sequenced power up of 5-V PTH modules. The output of the TPS3808 supervisor becomes active above an input voltage of 0.8 V, enabling it to assert a ground signal to the common track control well before the input voltage has reached the module's undervoltage lockout threshold. The ground signal is maintained until approximately 27ms after the input voltage has risen above U3's voltage threshold, which is 4.65V. The 27-ms time period is controlled by the capacitor C3. The value of 4700pF provides sufficient time delay for the modules to complete their internal soft-start initialization. The output voltage of each module remains at zero until the track control voltage is allowed to rise. When U3 removes the ground signal, the track control voltage automatically rises. This causes the output voltage of each module to rise simultaneously with the other modules, until each reaches its respective set-point voltage. Figure 23 shows the output voltage waveforms after input voltage is applied to the circuit. The waveforms, VO1 and VO2, represent the output voltages from the two power modules, U1 (3.3 V) and U2 (1.8 V), respectively. VTRK, VO1, and VO2 are shown rising together to produce the desired simultaneous power-up characteristic. The same circuit also provides a power-down sequence. When the input voltage falls below U3's voltage threshold, the ground signal is re-applied to the common track control. This pulls the track inputs to zero volts, forcing the output of each module to follow, as shown in Figure 24. Power down is normally complete before the input voltage has fallen below the modules' undervoltage lockout. This is an important constraint. Once the modules recognize that an input voltage is no longer present, their outputs can no longer follow the voltage applied at their track input. During a power-down sequence, the fall in the output voltage from the modules is limited by the Auto-Track slew rate capability. 24 Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 Notes on Use of Auto-Track™ 1. The Track pin voltage must be allowed to rise above the module set-point voltage before the module regulates at its adjusted set-point voltage. 2. The Auto-Track function tracks almost any voltage ramp during power up, and is compatible with ramp speeds of up to 1 V/ms. 3. The absolute maximum voltage that may be applied to the Track pin is the input voltage VI. 4. The module cannot follow a voltage at its track control input until it has completed its soft-start initialization. This takes about 20 ms from the time that a valid voltage has been applied to its input. During this period, it is recommended that the Track pin be held at ground potential. 5. The Auto-Track function is disabled by connecting the Track pin to the input voltage (VI). When Auto-Track is disabled, the output voltage rises according to its softstart rate after input power has been applied. 6. The Auto-Track pin should never be used to regulate the module's output voltage for long-term, steady-state operation. Auto Track VI = 5 V +Sense VI U1 PTH04T230W C4 0.1 mF VCC MR SENSE -Sense CT RESET VOAdj GND + 5 CO1 RSET1 1.21 kW CI1 U3 TPS3808G50 4 VO1 3.3 V VO 6 3 RTT TurboTrans 1 GND Auto Track 2 RTT TurboTrans +Sense C3 4700 mF VI U2 PTH04T240F VO2 1.8 V Vo -Sense + GND VOAdj RSET2 4.75 kW CI2 CO2 UDG-08157 Figure 22. Sequenced Power Up and Power Down Using Auto-Track Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 25 PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... www.ti.com VTRK (1 V/div) VTRK (1 V/div) VO1 (1 V/div) VO1 (1 V/div) VO2 (1 V/div) VO2 (1 V/div) T − Time − 200 µs/div T − Time − 20 ms/div Figure 23. Simultaneous Power Up With Auto-Track Control Figure 24. Simultaneous Power Down With Auto-Track Control Prebias Startup Capability A prebias startup condition occurs as a result of an external voltage being present at the output of a power module prior to its output becoming active. This often occurs in complex digital systems when current from another power source is backfed through a dual-supply logic component, such as an FPGA or ASIC. Another path might be via clamp diodes as part of a dual-supply power-up sequencing arrangement. A prebias can cause problems with power modules that incorporate synchronous rectifiers. This is because under most operating conditions, these types of modules can sink as well as source output current. The PTH family of power modules incorporate synchronous rectifiers, but does not sink current during startup(1), or whenever the Inhibit pin is held low. However, to ensure satisfactory operation of this function, certain conditions must be maintained(2). Figure 25 shows an application demonstrating the prebias startup capability. The startup waveforms are shown in Figure 26. Note that the output current (IO) is negligible until the output voltage rises above the voltage backfed through the intrinsic diodes. The prebias start-up feature is not compatible with Auto-Track. When the module is under Auto-Track control, it sinks current if the output voltage is below that of a back-feeding source. To ensure a pre-bias hold-off one of two approaches must be followed when input power is applied to the module. The Auto-Track function must either be disabled(3), or the module’s output held off (for at least 50 ms) using the Inhibit pin. Either approach ensures that the Track pin voltage is above the set-point voltage at start up. 1. Startup includes the short delay (approximately 10 ms) prior to the output voltage rising, followed by the rise of the output voltage under the module’s internal soft-start control. Startup is complete when the output voltage has risen to either the set-point voltage or the voltage at the Track pin, whichever is lowest. 2. To ensure that the regulator does not sink current when power is first applied (even with a ground signal applied to the Inhibit control pin), the input voltage must always be greater than the output voltage throughout the power-up and power-down sequence. 3. The Auto-Track function can be disabled at power up by immediately applying a voltage to the module’s Track pin that is greater than its set-point voltage. This can be easily accomplished by connecting the Track pin to VI. 26 Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 3.3 V Track VI = 5 V VI +Sense PTH04T240W Inhibit GND Vadj VO Vo = 2.5 V Io -Sense VCCIO VCORE + CI 330 mF RSET 2.37 kW CO 200 mF ASIC Figure 25. Application Circuit Demonstrating Prebias Startup VIN (1 V/div) VO (1 V/div) IO (2 A/div) t - Time = 4 ms/div Figure 26. Prebias Startup Waveforms Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 27 PTH04T240F SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 ............................................................................................................................................... www.ti.com TAPE AND REEL 28 Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F PTH04T240F www.ti.com ............................................................................................................................................... SLTS293A – DECEMBER 2008 – REVISED MARCH 2009 TRAY Submit Documentation Feedback Copyright © 2008–2009, Texas Instruments Incorporated Product Folder Link(s): PTH04T240F 29 PACKAGE OPTION ADDENDUM www.ti.com 16-Jul-2020 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) (3) Device Marking (4/5) (6) PTH04T240FAD ACTIVE ThroughHole Module EAY 11 49 RoHS Exempt & Green SN N / A for Pkg Type -40 to 85 PTH04T240FAS ACTIVE Surface Mount Module EAZ 11 49 Non-RoHS & Green SNPB Level-1-235C-UNLIM/ Level-3-260C-168HRS -40 to 85 PTH04T240FAZ ACTIVE Surface Mount Module BAZ 11 49 RoHS Exempt & Green SNAGCU Level-3-260C-168 HR -40 to 85 PTH04T240FAZT ACTIVE Surface Mount Module BAZ 11 250 RoHS Exempt & Green SNAGCU Level-3-260C-168 HR -40 to 85 (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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