DC/DC CONVERTERS

www.DataSheet4U.com www.ti.com PTB48560A, PTB48560B PTB48560C SLTS236A – MARCH 2005 – REVISED OCTOBER 2005 30-W, 48-V INPUT DC/DC CONVERTERS WITH AUTO-TRACK™ SEQUENCING FEATURES • • • • • • • • • • • • • • • • Input Voltage: 36 V to 75 V 30-W Total Output Power Output Voltages: 3.3 V, 5 V, and 12 V Wide-Output Adjust/Trim Up To 88% Efficiency Overcurrent Protection Overtemperature Shutdown Undervoltage Lockout Input Overvoltage Protection Auto-Track™ Power-Up Sequencing (Includes Sequenced Output with PTB48560B) Smart-Sense Remote Sensing (PTB48560B) Dual-Logic Enable Control Space-Saving 1×2 Footprint Surface Mount Package 1500-Vdc Isolation Agency Approvals (Pending): UL/cUL 60950, EN 60950 APPLICATIONS • • • Intermediate Bus Architectures Telecom, High-End Computing Platforms Multi-Rail Power Systems with Power-Up Sequencing DESCRIPTION The PTB48560x is a series of 30–W rated isolated dc/dc converters, designed to operate from a standard -48–V telecom central office (CO) supply. Housed in a 1×2 package, each model has a wide-adjust output voltage that can be set to one of the common intermediate bus voltages of 3.3 V, 5 V, or 12 V. The PTB48560 series incorporates Auto-Track™, a feature that simplifies the power-up sequencing of multiple power modules and operates from the same intermediate bus. During a power-up cycle, modules with this feature have the capability of following a common ramp voltage applied to an input called Track. The PTB48560 series is specifically designed to control the Track voltage of any number of nonisolated downstream modules powered from its output. This ensures that the outputs of the downstream modules all rise simultaneously during power up. The PTB48560B (3.3 V) has an additional sequenced output, VO Seq, which also rises with the Track voltage. This allows the VO Seq output to power up simultaneously with the outputs from other power modules under the control of Auto-Track. Whether used to facilitate power-up sequencing, or operated as a stand-alone module, the PTB48560 series includes many other features expected of high-performance dc/dc converter modules. Precise output voltage regulation is ensured with a differential remote sense. Operational features include an input undervoltage lockout (UVLO) and a dual-logic output enable control. Overcurrent and overtemperature protection ensure survival against load faults.Typical applications include distributed power architectures in both telecom and computing environments, particularly complex digital systems requiring power sequencing of multiple power supply rails. 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 is a trademark 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 © 2005, Texas Instruments Incorporated PTB48560A, PTB48560B PTB48560C SLTS236A – MARCH 2005 – REVISED OCTOBER 2005 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. Typical Circuit Track PTB48560x +VI 1 +VI +Sense* 9 See Note (*) 5 VOSeq (3.3 V) # 11 VOSeq # 10 VOBus 2 3 PEN VOAdjust NEN VOCOM -VI 4 -VI - Sense 6 7 RSET† 8 CO ‡ (Required) Track VI Auto-Track V POL Module O GND Adjust CI ‡ CO RSET VPOL1 Track Simultaneous Power-Up VOSeq # VPOL1 VPOL2 To Other POL Modules # Sequenced output is only available with the PTB48560B. CI ‡ VI Auto-Track V POL Module O GND Adjust RSET CO VPOL2 † * The +Sense can be connected to either the VOSeq or VOBus output of the PTB48560B. †R SET is required to set the output voltage higher than the minimum value; see the Application Information for values. ‡ The PTB48560x modules require a minimum total output capacitance for proper operation; see the Electrical Characterisitics for the value required by each model. 2 www.ti.com PTB48560A, PTB48560B PTB48560C SLTS236A – MARCH 2005 – REVISED OCTOBER 2005 ORDERING INFORMATION PTB48560 (Base Pt. Number) Output Voltage Range Part Number PTB48560AAH 3.6 V to 5.5 V PTB48560AAS PTB48560AAZ PTB48560BAH 1.8 V to 3.6 V PTB48560BAS PTB48560BAZ 9 V to o13.2 V (4) (4) (4) DESCRIPTION Horizontal T/H Standard SMD Optional SMD Standard SMD Optional SMD Standard SMD Optional SMD (2) (3) Pb – free and RoHS Compatible Yes No Yes Yes No Yes Yes No Yes Package Ref. ERW ERY ERW ERY ERW ERY (1) Horizontal T/H (2) (3) PTB48560CAH PTB48560CAS PTB48560CAZ (1) (2) (3) (4) Horizontal T/H (2) (3) See the applicable package reference drawing for the dimensions and PC board layout. Standard option specifies 63/37, Sn/Pb pin solder material. Lead (Pb) – free option specifies Sn/Ag pin solder material. Includes an Auto-Track compatible output, VO Seq, which sequences with the Track control during power up. ABSOLUTE MAXIMUM RATINGS PTB48560x VI V(Track) I(Track) max TA 1 T(WAVE) T(REFLOW) Tstg (1) (2) (3) Input Voltage Track input voltage Track input current Operating temperature range Overtemperature protection Wave solder temperature Solder reflow temperature Storage temperature From external source Over VI range PCB temperature (near pin 1) Surface temperature of module or pins (5 seconds) Surface temperature of module or pins PTB48560xAH PTB48560xAS PTB48560xAZ Continuous Surge, 1 s max 75 100 (1) 0 to VO Bus + 0.3 10 (2) UNIT V mA –40 to 85 115 260 (3) °C 235 260 (3) (3) –40 to 125 The converter's internal protection circuitry may cause the output to turn off when the applied input voltage is greater than 75 V. When the Track input is fed from an external voltage source, the input current must be limited. A 2.74-kΩ value series resistor is recommended. During solder reflow of SMD package version, do not elevate the module PCB, pins, or internal component temperatures this peak temperature. PACKAGE SPECIFICATIONS PTB48560x (Suffixes AH and AS) Weight Flammability Mechanical shock Mechanical vibration (1) Qualification limit. Meets UL94V-O Per Mil-STD-883D, Method 2002.3, 1 ms, 1/2 Sine, mounted Mil-STD-883D, Method 2007.2, 20-2000 Hz, PCB mounted Horizontal T/H (Suffix AH) Horizontal SMD (Suffix AS) Horizontal T/H (Suffix AH) Horizontal SMD (Suffix AS) 500 Gs 250 G 20 G 5G (1) (1) (1) (1) 13.6 grams 3 PTB48560A, PTB48560B PTB48560C SLTS236A – MARCH 2005 – REVISED OCTOBER 2005 www.ti.com PTB48560B ELECTRICAL CHARACTERISTICS (Unless otherwise stated, TA = 25°C, VI = 48 V, VO = 3.3 V, CO = 220 µF, and IO = IOmax) PARAMETER Over VI range IO VI Output current Input voltage range Set-point voltage tolerance Temperature variation VO Line regulation Load regulation Total output voltage variation Adjust range η Efficiency VO Ripple (peak-to-peak) Transient response 20-MHz bandwidth 0.1 A/µs load step, 50% to 100% IOmax Input current Track input (pin 5) Open-circuit voltage Input slew rate limits Referenced to -VI Output enable inputs (pins 2, 3) Standby input current IO (tot) UVLO ƒS Overcurrent threshold Undervoltage lockout Switching frequency Internal input capacitance External output capacitance Isolation voltage Isolation capacitance Isolation resistance MTBF (1) (2) (3) (4) (5) (6) Reliability Between both outputs and VO COM Input-output Input-output Input-output Telcordia SR-332 50% stress, TA = 40°C, ground benign 10 3.6 220 1,500 2,000 Over VI range Pins 2 and 3 open Shutdown, followed by autorecovery VI increasing VI decreasing 400 Input high voltage (VIH) Input low voltage (VIL) Input low current (IIL) 0.1 Recovery time VO over/undershoot Track connected to -Sense 0 (5) TEST CONDITIONS IO Bus IO Seq Sum total, (IO Bus + IO Seq) Over IO range -40°C ≤ TA ≤ 85°C Over VI range Over IO range Includes set-point, line, load, –40°C ≤ TA ≤ 85°C Over VI range RSET = 5.36 kΩ, VO = 3.3 V RSET = 40.2 kΩ, VO = 2.5 V RSET = open , VO = 1.8 V PTB48560B MIN 0.25 (1) TYP MAX 8 4 (2) (3) UNIT 0 0.25 36 ±1 48 (4) A V %VO %VO 8 75 ±0.5 ±7 ±13 ±2 1.8 82% 79% 74% 50 100 ±150 -0.13 VO Bus 1 Open 0.48 8 12 34 33 500 1 5,000 600 16 (6) ±33 ±33 ±3 (4) mV mV %VO V 3.6 mVpp µs mV mA V/ms V mA mA A V kHz µF µF Vdc pF MΩ 106 Hr 2 -0.2 0.8 The converter requires a minimum load current at either the VO Seq or VO Bus output for proper operation. The converter is not damaged when operated under a no-load condition. See temperature derating curves for safe operating area (SOA), to determine output current derating at elevated ambient temperatures. When load current is supplied from the VO Seq output, the module exhibits higher power dissipation and slightly lower operating efficiency. 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 temperature stability. When controlling the Track input from an external source, the slew rate of the applied signal must be greater than the minimum limit. Failure to allow the voltage to completely rise to the voltage at the VO (bus) output, at no less than the minimum specified rate, may thermally overstress the converter. The PEN and NEN inputs each have an internal pullup resistor. If the enable feature is not used, the PEN input (pin 2) should be left open circuit and the NEN input (pin 3) permanently connected to –VI. A discrete MOSFET or bipolar transistor is recommended for the enable control. The open-circuit voltage is less than 10 V. See the Application Information for a more detailed description. 4 www.ti.com PTB48560A, PTB485