PT4472 TI | Alldatasheet

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Technical content

Features

  • 18V to 36V Input Voltage Range
  • Programmable Output Voltage Range: 1.3V to 3.5V
  • -40° to +85°C Ambient
  • 1500 VDC Isolation
  • 89% Efficiency
  • On/Off Inhibit
  • Differential Remote Sense
  • 60A Output with PT4495 SLTS094C (Revised 6/21/2002)

Description

The PT4472 Excalibur™ DC/DC converter module combines state-of-the- art power conversion technology with un-paralleled flexibility. Incorporating high efficiency and ultra-fast transient response, these modules provide up to 30A of output current over the program- mable voltage range of 1.3V to 3.5V. This represents a full 100W output at 3.3V. The modules include a number of inbuilt features to facilitate system integration. These include a foldback output current limit, over-temperature protection, and an inhibit on/off control. A differential remote sense is also provided to compensate for voltage drop between the converter and load. For additional output current, one PT4472 may be operated with up to two PT4495 compatible booster modules. Each PT4495 adds an additional 30A of output current capability.

  • Over-Current Protection
  • Over-Temperature Protection
  • Over-Voltage Protection
  • Space-Saving Package
  • Solderable Copper Case
  • Safety Approvals: UL 60950 CSA 22.2 950 VDE EN60950 Pending L O A D PT4472 +V sns +V out -V out -Vsns 8-13 14-19 202522 2423 VID0 - VID4 +V in –V in InhibitC 1 PROGRAMMING PINS +V OUT +V IN –V IN –V OUT C o C 2
  • C o = Optional 330µF electrolytic capacitor
  • C 1 = Optional 33µF, 50V electrolytic capacitor
  • C 2 = Optional 1µF, 50V ceramic capacitor
  • Programming pins, VID0–VID4, are shown configured for Vo =3.3V
  • For normal operation, pin 3 (Inhibit) must be connected to –Vin.

Ordering Information

PT4472/G6F = 1.3 to 3.5 Volts PT4495/G6F = 30-A Booster PT Series Suffix (PT1234x) Case/Pin Order Package Configuration Suffix Code * Vertical N (EKD) Horizontal A (EKA) SMD C (EKC) * Previously known as package styles 1200, 1210, and 1215. (Reference the applicable package code draw- ing for the dimensions and PC board layout) Pin-Out Information Pin Function 1+ V in 2– V in

3 Inhibit

4V r † 5V a †

6 Do not connect

7 (+)Remote Sense 8+ V out 9+ V out 10 +Vout 11 +Vout 12 +Vout 13 +Vout Pin Function 14 –V out 15 –V out 16 –V out 17 –V out 18 –V out 19 –V out 20 (–)Remote Sense

21 VID0

22 VID1

23 VID2

24 VID3

25 VID4

26 DRV †

PT4472—24V 100-W 30-A Programmable Isolated DC/DC Converter † Pins 4, 5, & 26 are used for booster applications. For stand-alone operation, leave open circuit.

  • Shaded functions indicate those pins that are referenced to primary-side potential.

For technical support and more information, see inside back cover or visit www.ti.com PT4470 Series Comparison Output Voltage Configuration for Functionality Program Range Current Sharing PT4471 Regulator 1.3V– 3.5V N+1 with other PT4471s PT4472 Regulator 1.3V– 3.5V With PT4495 boosters PT4495 PT4472 Booster N/A Used only with PT4472 PT4473 Regulator 4.6V–5.7V N+1 with other PT4473s PT4474 Regulator 4.6V–5.7V With PT4494 boosters PT4494 PT4474 Booster N/A Used only with PT4474 PT4475 Regulator 6.5V– 17.5V N+1 with other PT4475s PT4476 Regulator 6.5V–17.5V With PT4493 boosters PT4493 PT4476 Booster N/A Used only with PT4476 PT4472— 24V 100-W 30-A Programmable Isolated DC/DC Converter Programming Information VID4=1 VID4=0 VID3 VID2 VID1 VID0 Vout Vout 1 1 1 1 2.0V 1.30V 1 1 1 0 2.1V 1.35V 1 1 0 1 2.2V 1.40V 1 1 0 0 2.3V 1.45V 1 0 1 1 2.4V 1.50V 1 0 1 0 2.5V 1.55V 1 0 0 1 2.6V 1.60V 1 0 0 0 2.7V 1.65V 0 1 1 1 2.8V 1.70V 0 1 1 0 2.9V 1.75V 0 1 0 1 3.0V 1.80V 0 1 0 0 3.1V 1.85V 0 0 1 1 3.2V 1.90V 0 0 1 0 3.3V 1.95V 0 0 0 1 3.4V 2.00V 0 0 0 0 3.5V 2.05V Logic 0 = Connect to (–)Remote Sense, pin 20 Logic 1 = Open circuit (no pull-up resistors) VID3 & VID4 must not be changed while unit is operating Specifications (Unless otherwise stated, Ta =25°C, Vin =24V, Vo =3.3V, Co =0µF, and Io =Iomax) PT4472 Characteristic Symbol Conditions Min Typ Max Units Output Current I o Over Vin range 0 — 30 A Input Voltage Range V in Over Io Range 18 24 36 VDC Set Point Voltage Tolerance V o tol — ±1 ±1.5 %V o Temperature Variation Reg temp –40° ≤Tcase ≤ +100°C, Io =0 — ±0.5 — %V o Line Regulation Reg line Over Vin range — ±0.1 ±1 %V o Load Regulation Reg load Over Io range — ±0.2 ±1 %V o Total Output Voltage Variation ∆Votot Includes set-point, line, load, —± 2± 3% V o–40° ≤Tcase ≤ +100°C Efficiency η Io =15A V o =3.3V — 89 — Vo =2.5V — 87 — % Vo =1.5V — 81 — Vo Ripple (pk-pk) V r 20MHz bandwidth V o >2V — 60 75 mVppVo ≤2V — 45 55 Transient Response t tr 0.1A/µs load step, 50% to 75% Iomax — N/A — µs ∆Vtr Vo over/undershoot — 1 — %V o 1A/µs load step, 50% to 100% Iomax — 75 — µs Vo over/undershoot — ±5 — %V o Current Limit I lim Vin =18V, ∆Vo = –1% —3 5—Afoldback continuous limit Current Share Tolerance I shr tol with PT4495 booster — ±10 — % Over-Voltage Protection OVP Shutdown and latch off — 125 — %V o Switching Frequency ƒ s Over Vin range 270 300 350 kHz Under-Voltage Lockout UVLO — 17 — V Inhibit (Pin 3) Referenced to –V in (pin 2) Input High Voltage V IH 2.5 — Open (1) V Input Low Voltage VIL –0.5 — +0.8 Input Low Current IIL — –0.2 — mA Standby Input Current I in standby pins 3 & 2 connected — 4 10 mA Internal Input Capacitance C in —3 —µ F External Output Capacitance C out Between +Vo and –Vo 0 — 10,000 µF Isolation Voltage Input–output/input–case 1500 — — V Capacitance Input to output — 1100 — pF Resistance Input to output 10 — — M Ω Operating Temperature Range T c Case temperature, over Vin range -40 — +115 (2) °C Over-Temperature Shutdown OTP Case temperature, auto reset — 120 — °C Storage Temperature T s — -40 — +125 °C Reliability MTBF Per Bellcore TR-332 1.4 — — 10 6 Hrs50% stress, Ta =40°C, ground benign Mechanical Shock — Per Mil-Std-883D, method 2002.3, — 500 — G’s 1mS, half-sine, mounted to a fixture Mechanical Vibration — Mil-Std-883D, Method 2007.2 Horizontal — 20 (3) —G ’ s 20-2000Hz, pcb mounted Weight — — — 90 — grams Flammability — Materials meet UL 94V-0 Notes: (1) The Inhibit (pin 3) has an internal pull-up, which if left open circuit allows the converter to operate when input power is applied. The open-circuit is limited to 6.5V. Refer to the application notes for interface considerations. (2) See Safe Operating Area curves or contact the factory for the appropriate derating. (3) The case pins on through-hole pin configuration (suffix A) must be soldered. For more information see the applicable package outline drawing. # This specification covers only the PT4472 regulator and PT4495 current booster.

For technical support and more information, see inside back cover or visit www.ti.com Note A: Characteristic data has been developed from actual products tested at 25°C. This data is considered typical data for the Converter. Note B: SOA curves represent the conditions at which internal components are at or below the manufacturer’s maximum operating temperatures Efficiency vs Output Current Ripple vs Output Current Power Dissipation vs Output Current Typical CharacteristicsPT4472— 24V 100-W 30-A Programmable Isolated DC/DC Converter Stand Alone, No Heatsink Safe Operating Area, Vin =24V (See Note B)Performance Characteristics, Vo =3.3V (See Note A) 0 5 10 15 20 25 30 Iout (A) Pd - Watts 18.0V 24.0V 36.0V VIN 0 5 10 15 20 25 30 Iout (A ) Ambient Temperature (°C) 500LFM 400LFM 300LFM 200LFM 100LFM Nat conv Airflow 100 0 5 10 15 20 25 30 Iout (A ) Efficiency - % 3.3V 2.5V 1.5V VOUT 100 0 5 10 15 20 25 30 Iout (A ) Ripple - mV 3.3V 2.5V 1.5V VOUT

For technical support and more information, see inside back cover or visit www.ti.com Application Notes Increasing the Output Current of the PT4472 with the PT4495 Compatible Current Booster The PT4495 is a 30-A “Current Booster” module designed specifically for the PT4472 programmable DC/DC converter. The booster is controlled directly by the regulator, and effectively adds an additional output stage that operates in parallel. This allows the system to run sychronously, providing a low noise solution. Up to two booster modules can be connected to a PT4472 converter. Each booster module increases the available output current by 30A. A combination of one PT4472 converter and two PT4495 booster modules can supply up to 90A of output current; enough to supply virtually any multi-processor application. Figure 1-1 shows the connection schematic for the regulator and current booster combination. A current booster is not a stand-alone product, and can only operate with a regulator. It is housed in the same package as its compatible r egulator, and shares the same mechanical outline. Except for an increase in output current, the overall performance of a converter/booster combination is identical to that of a stand-alone converter. Figure 1-1; Current Booster Application Schematic Table 1-1; Booster Pin-Out Information Pin Function Pin Function Pin Function 1+ V in 10 +Vout 19 –Vout 2– V in 11 +Vout 20 (–)Vsense

3 Do not connect 12 +V out 21 Do not connect

4V r 13 +Vout 22 Do not connect 5V a 14 –Vout 23 Do not connect

6 Do not connect 15 –V out 24 Do not connect

7 Do not connect 16 –V out 25 Do not connect

8+ V out 17 –Vout 26 DRV 9+ V out 18 –Vout Notes: 1. Refer to the PT4472 specification table for the performance of the regulator/booster combination. 2. The pin-out of the current booster modules include a number pins identified, “Do not connect” (see Table 1-1). These pins are not connected internally to the module but must be soldered to a pad to preserve the unit’s mechanical integrity. 3. A minimum of 330µF of output capacitance is required across the output of each PT4495 booster for proper operation. A value greater than 330µF will further reduce transients due to large and/or fast load steps. 4. The converter and all boosters must be located on the same printed circuit board. A similar footprint and trace layout for each module will also facilitate current sharing. PT4472, PT4495 PT4495 PT4472 8 - 13 –VIN -VOUT +VOUT REMOTE SENSE (+) REMOTE SENSE (-) VID0 VID1 VID2 VID3 PROGRAMMING PINS Inhibit 3C IN 33µF Optional C IN 33µF Optional LOAD 1 8 - 13 14 - 19 +VIN 25VID4 24 23 22 21 14-19 452 6 20452 6 C OUT 330µF Optional C OUT 330µF Required 3

For technical support and more information, see inside back cover or visit www.ti.com Operating Features of the PT4470 and PT4480 Series of Isolated DC/DC Converters Under-Voltage Lockout An Under-Voltage Lock-Out (UVLO) inhibits the operation of the converter until the input voltage is above the UVLO threshold (see the applicable data sheet specification). Below this voltage, the module’s output is held off, irrespective of the state of the Inhibit control (pin 3). If the Inhibit control is connected to –V in (pin 2), the module will automatically power up when the input voltage rises above the UVLO threshold. The UVLO allows the module to produce a clean transition during both power-up and power-down, even when the input voltage is rising or falling slowly. It also reduces the high start-up current during normal power-up of the converter, and minimizes the current drain from the input source during low-input voltage conditions. The UVLO threshold includes about 2V of hysteresis. Once operational, the con verter will conform to its operating specifications when the minimum specified input voltage is reached. Over-Current Protection To protect against load faults, the PT4470/80 series of DC/DC converters incorporate an output current limit. Once the load current drawn from the module reaches the current limit threshold, any attempt by the load to draw additional current will result in a significant drop in the module’s regulated output voltage. The current limit circuitry incorporates a limited amount of foldback. This has the effect of slightly reducing the output current from the module when supplying an absolute short circuit. Upon removal of the load fault, the output voltage from the converter will automatically recover to its programmed regulation voltage. Output Over-Voltage Protection The PT4470/80 series of DC/DC converters incorporate circuitry that continually senses the output for an over- voltage (OV) condition. The OV threshold automatically tracks the VID output voltage program setting to a level 25% higher than that programmed at the control pins, VID0 through VID4. If the converter output voltage exceeds the OV threshold, the converter is immediately shut down and remains in a latched-off state. To resume normal operation the converter must be actively reset. This is accomplished by either cycling the status of the Inhibit control (pin 3) from “On” to “Off” and then back “On” again, or by momentarily removing the input power to the converter. For failsafe operation and redundancy, the OV protection uses circuitry that is independent of the converter’s internal feedback loop. Over-Temperature Protection Over-temperature protection is provided by an internal temperature sensor, which closely monitors the tempera- ture of the converter’s metal case. If the case temperature exceeds the specified limit (see applicable data sheet), the converter will shut down. The converter will then automatically restart when the sensed temperature drops by about 10°C. When operated outside its recommended thermal derating envelope (see data sheet SOA curves), the converter will typcially cycle on and off at intervals from a few seconds to one or two minutes. This is to ensure that the internal components are not permanently damaged from excessive thermal stress. Primary-Secondary Isolation Electrical isolation is provided between the input terminals (primary) and the output terminals (secondary). All con- verters are production tested to a primary-secondary withstand voltage of 1500VDC. This specification com- plies with UL60950 and EN60950 and the requirements for operational isolation. Operational isolation allows these converters to be configured for either a positive or negative input voltage source. The data sheet ‘Pin-Out Information’ uses shading to indicate which pins are associated with the primary. They include pins 1 through 5, inclusive. Fuse Recommendations If desired, an input fuse may be added to protect against the application of a reverse input voltage. Thermal Considerations Airflow may be necessary to ensure that the module can supply the desired load current in environments with elevated ambient temperatures. The required airflow rate may be determined from the Safe Operating Area (SOA) thermal derating chart (see converter specifica- tions). The recommended direction for airflow is into the longest side of the module’s metal case. See Figure 1. Recommended direction for airflow is into (perpendicular to) the longest side. Figure 1 PT4470, PT4480 Series

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