PT4410 Series 100-Watt 48-V Input Isolated DC/DC Converter SLTS170C - JULY 2002 - REVISED JUNE 2003 Features • Input Voltage Range: 36 V to 75 V • Programmable Output Voltage • +90 % Efficiency • 1500 VDC Isolation • On/Off Control • Over-Current Protection • Differential Remote Sense • Output Over-Voltage Protection • Over-Temperature Shutdown Description Ordering Information The PT4410 series of power modules are singleoutput isolated DC/DC converters, housed in a compact 21-pin low-profile (12 mm) package. These modules are rated up to 100W with load currents as high as 30 A. The output voltage is set within a pre-defined range via a 5-bit input code. The PT4410 series operates from a standard 48-V telecom CO supply and occupies only 3.9 in² of PCB area. These modules offer OEMs a compact and flexible high-output power source for use with high-end microprocessors, DSPs, general purpose logic and analog. They are suitable for distributed power applications in both telecom and computing environments. Features include output over-current protection, on/off control, output over-voltage protection (OVP), over-temperature shutdown, under-voltage lockout (UVLO), and an output differential remote sense. The modules are fully integrated for stand-alone operation, and require no additional components. The horizontal package outline is also comparable to industry standard ¼-bricks, allowing for a dual PWB layout. PT4411H = 1.3 to 3.5 Volts PT4412H = 1.05 to 1.75Volts PT4413H = 3.4 to 5.7 Volts • Undervoltage Lockout • Low Profile Package (12mm) • Compact Footprint Comparable to ¼-Brick: (Horiz Config. 1.45 in × 2.6 in, Vertical Config. < 1 in2) • Surface Mountable • Agency Approvals: UL 60950, CSA 22.2 950 • IPC Lead Free 2 Pin-Out Information Pin Function PT Series Suffix (PT1234 x ) Case/Pin Configuration Order Suffix Package Code N A C (ENM) (ENN) (ENP) Vertical Horizontal SMD (Reference the applicable package code drawing for the dimensions and PC layout) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Remote On/Off * -Vin -Vin +Vin +Vin Pin Not Present VID 0 VID 1 VID 2 VID 3 VID 4 † (–)Remote Sense -Vo -Vo -Vo -Vo +Vo +Vo +Vo +Vo (+)Remote Sense * For more information consult the applicable application note. † VID 4 does not function on the PT4412 & PT4413 Standard Application + REMOTE SENSE + V sns + C IN 100µF + V in + V out 17–20 PT4411 2, 3 – V in -V out Remote On/Off 1 VID0 - VID4 7 8 9 10 11 13–16 C OUT 330µF L O A D + 4, 5 – V IN + V OUT 21 + V IN – V OUT -V sns 12 – REMOTE SENSE PROGRAMMING PINS # For technical support and more information, see inside back cover or visit www.ti.com Notes: CIN =Optional 100 µF electroliytic capacitor C OUT =Optional 330 µF electrolytic capacitor # VID programming pins are set for 3.3 V output PT4410 Series 100-Watt 48-V Input Isolated DC/DC Converter SLTS170C - JULY 2002 - REVISED JUNE 2003 Environmental Specifications Characteristics Symbols Conditions Min Typ Max Units Operating Temperature Range ShutdownTemperature Solder Reflow Temperature Storage Temperature Mechanical Shock Ta OTP Treflow Ts Over Vin Range Case temperature - auto reset Surface temperature of module pins or case — Per Mil-STD-883D, Method 2002.3 1 msec, ½ Sine, mounted Mil-STD-883D, Method 2007.2 Vertical 20-2000 Hz, PCB mounted Horizontal Vertical/Horizontal Meets UL 94V-O –40 — — –40 — 115 — — +85 (i) — 215 (ii) +125 °C °C °C °C — — — — 500 15 (iii) 20 (iii) 50 — — — — G’s Mechanical Vibration Weight Flammability — — G’s grams Notes (i) See SOA curves or consult factory for appropriate derating (ii) During solder reflow of SMD package version, do not elevate the module case, pins, or internal component temperatures above a peak of 215 °C. For further guidance refer to the application note, “Reflow Soldering Requirements for Plug-in Power Surface Mount Products,” (SLTA051). (iii) The case pins on the through-hole package types (suffixes N &A) must be soldered. For more information see the applicable package outline drawing. Output Voltage Programming Information PT4411 VID3 VID2 VID1 VID0 VID4=1 Vout VID4=0 Vout PT4412 PT4413 VID4= NC Vout VID4= NC Vout 1 1 1 1 1 1 1 0 N/D * 2.10 V 1.30 V 1.35 V N/D * 1.05 V 1 1 1 1 0 0 1 0 2.20 V 2.30 V 1.40 V 1.45 V 1.10 V 1.15 V 1 1 0 0 1 1 1 0 2.40 V 2.50 V 1.50 V 1.55 V 1.20 V 1.25 V 1 1 0 0 0 0 1 0 2.60 V 2.70 V 1.60 V 1.65 V 1.30 V 1.35 V 0 0 1 1 1 1 1 0 2.80 V 2.90 V 1.70 V 1.75 V 1.40 V 1.45 V 0 0 1 1 0 0 1 0 3.00 V 3.10 V 1.80 V 1.85 V 1.50 V 1.55 V 0 0 0 0 1 1 1 0 3.20 V 3.30 V 1.90 V 1.95 V 1.60 V 1.65 V 0 0 0 0 0 0 1 0 3.40 V 3.50 V 2.00 V 2.05 V 1.70 V 1.75 V Logic 0 =Pin 12 potential; (–)Remote Sense Logic 1 =Open circuit (no pull-up resistors) N/D * 3.40 V 3.56 V 3.72 V 3.88 V 4.05 V 4.21 V 4.37 V 4.53 V 4.69 V 4.86 V 5.02 V 5.18 V 5.34 V 5.50 V 5.67 V * N/D = Voltage is not defined. The regulator produces a low-voltage periodic pulse (less than 1 V) approximately every 10 ms. Note: During operation, changes to the program code should be limited to 15 % of Vo so as to avoid activating the output O V protection. Pin Descriptions +Vin: The positive input for the module with respect to –Vin. When powering the module from a –48-V telecom central office supply, this input is connected to the primary system ground. +Vo: The positive power output with respect to -Vo, which is DC isolated from the input supply pins. If a negative output voltage is desired, +Vo should be connected to the secondary circuit common and the output taken from –Vo. –Vin: The negative input supply for the module, and the 0 VDC reference for the Remote On/Off input. When powering the module from a +48-V supply, this input is connected to the 48-V(Return). –Vo: The negative power output with respect to +Vo, which is DC isolated from the input supply pins. This output is normally connected to the secondary circuit common when a positive output voltage is desired. Remote On/Off: An open-collector (open-drain) positive logic input that is referenced to –Vin. Pulling this input down to –Vin potential disables the module’s output. If this input is left open-circuit, the module will produce an output whenever a valid input source is applied. +Remote Sense: Provides the converter with remote sense capability to regulate the set-point voltage directly at the load. When used with –Remote Sense, the regulation circuitry will compensate for voltage drop between the converter and the load. The pin may be left open circuit, but connecting it to +Vo will improve load regulation. VID0 – VID4: Selects the set-point output voltage of the converter according to the applicable program code. VID0 – VID4 must either be connected to (–)Remote Sense or left open circuit. Note: For the PT4412, VID 4 is internally disabled and may be left open circuit. –Remote Sense: This is the logic ‘0’ reference for the inputs VID0 – VID4, and provides the converter with remote sense capability when used in conjunction with +Remote Sense. For optimum output voltage accuracy this pin should always be connected to –Vo. For technical support and more information, see inside back cover or visit www.ti.com PT4411—48 V 100-Watt 48-V Input Isolated DC/DC Converter PT4411 Specifications SLTS170C - JULY 2002 - REVISED JUNE 2003 (Unless otherwise stated, T a =25 °C, Vin =48 V, Vo =3.3 V, C o =0 µF, and Io =Iomax) Characteristic Symbol Conditions Min PT4411 Typ Max Units Output Current Input Voltage Range Set Point Voltage Tolerance Temperature Variation Line Regulation Load Regulation Total Output Voltage Variation Io Vin Vo tol Regtemp Regline Regload ∆Votot Over Vin range Over Io Range 0 36 — — — — — 48 ±0.6 (1) ±0.8 ±1 ±1 30 75 — — — — A V %Vo %Vo mV mV — ±1.6 ±3 %Vo Efficiency Vo Ripple (pk-pk) Transient Response η Vr ttr ∆Vtr ITRIP OVP ƒo UVLO — — — — — — 250 — 91 50 75 ±5 36 125 300 32 — — — — — — 350 — % mVpp µs %Vo A %Vo kHz V 4.5 –0.2 — — — 0 1500 — 10 — — –0.3 2 1.4 Open (2) +0.8 — — — 5,000 — — — V Over-Current Threshold Output Over-Voltage Protection Switching Frequency Under-Voltage Lockout Remote On/Off Input Input High Voltage Input Low Voltage Input Low Current –40° >Ta > +85 °C Over Vin range Over Io range Includes set-point, line, load, –40° >Ta > +85 °C Io =15 A 20 MHz bandwidth 1 A/µs load step, 50 % to 100 % Iomax Vo over/undershoot Shutdown, followed by auto-recovery Output shutdown and latch off Over Vin range Referenced to –Vin VIH VIL IIL Iin standby Cin Cout Standby Input Current Internal Input Capacitance External Output Capacitance Isolation Voltage Capacitance Resistance pins 1 & 2 connected Between +Vo and –Vo Input-output & input-case Input-output Input-output — 1200 — mA mA µF µF Vdc pF MΩ Notes: (1) If (–)Remote Sense is not used, pin 12 must be connected to pin 13 for optimum output voltage accuracy. (2) The Remote On/Off input has an internal pull-up. If it is left open-circuit the module will operate when input power is applied. A discrete MOSFET or bipolar transistor is recommended to control this input. The open-circuit voltage is typically 5 V. See application notes for interface considerations. PT4411 Characterstic Data Power Dissipation vs Load Current; Vo =3.3 V (See Note A) Efficiency vs Load Current; Vin =48 V (See Note A) 100 15 90 12 3.3V 2.5V 1.8V 1.5V 80 70 VIN Pd - Watts Efficiency - % VOUT 60 75.0V 60.0V 48.0V 36.0V 9 6 3 50 0 0 5 10 15 20 25 30 0 5 10 Iout (A) 15 20 25 30 Iout (A) Output Ripple vs Load Current; Vin =48 V (See Note A) Safe Operating Area; Vin =48 V (See Note B) 90 100 Ripple - mV VOUT 3.3V 2.5V 1.8V 1.5V 60 40 20 Ambient Temperature (°C) 80 80 Airflow 70 400LFM 300LFM 200LFM 100LFM Nat conv 60 50 40 30 20 0 0 5 10 15 20 25 30 0 Iout (A) 5 10 15 20 25 30 Iout (A) Note A: All data listed in the above graphs has been developed from actual products tested at 25 °C. This data is considered typical data for the DC/DC converter. Note B: SOA curves represent operating conditions at which internal components are at or below manufacturer’s maximum rated operating temperature. For technical support and more information, see inside back cover or visit www.ti.com PT4412—48 V 100-Watt 48-V Input Isolated DC/DC Converter PT4412 Specifications SLTS170C - JULY 2002 - REVISED JUNE 2003 (Unless otherwise stated, T a =25 °C, Vin =48 V, Vo =1.5 V, C o =0 µF, and Io =I omax) Characteristic Symbol Conditions Min PT4412 Typ Max Units Output Current Input Voltage Range Set Point Voltage Tolerance Temperature Variation Line Regulation Load Regulation Total Output Voltage Variation Io Vin Vo tol Regtemp Regline Regload ∆Votot Over Vin range Over Io Range 0 36 — — — — — 48 ±0.6 (1) ±0.8 ±1 ±1 30 75 — — — — A V %Vo %Vo mV mV — ±1.6 ±3 %Vo Efficiency Vo Ripple (pk-pk) Transient Response η Vr ttr ∆Vtr ITRIP OVP ƒo UVLO — — — — — — 225 — 86.5 30 75 ±5 38 125 275 32 — — — — — — 325 — % mVpp µs %Vo A %Vo kHz V 4.5 –0.2 — — — 0 1500 — 10 — — –0.3 2 1.4 Open (2) +0.8 — — — 5,000 — — — V Over-Current Threshold Output Over-Voltage Protection Switching Frequency Under-Voltage Lockout Remote On/Off Input Input High Voltage Input Low Voltage Input Low Current –40° >Ta > +85 °C Over Vin range Over Io range Includes set-point, line, load, –40° >Ta > +85 °C Io =15 A 20 MHz bandwidth 1 A/µs load step, 50 % to 75 % Iomax Vo over/undershoot Shutdown, followed by auto-recovery Output shutdown and latch off Over Vin range Referenced to –Vin VIH VIL IIL Iin standby Cin Cout Standby Input Current Internal Input Capacitance External Output Capacitance Isolation Voltage Capacitance Resistance pins 1 & 2 connected Between +Vo and –Vo Input-output & input-case Input-output Input-output — 1200 — mA mA µF µF Vdc pF MΩ Notes: (1) If (–)Remote Sense is not used, pin 12 must be connected to pin 13 for optimum output voltage accuracy. (2) The Remote On/Off input has an internal pull-up. If it is left open-circuit the module will operate when input power is applied. A discrete MOSFET or bipolar transistor is recommended to control this input. The open-circuit voltage is typically 5 V. See application notes for interface considerations. PT4412 Characterstic Data Power Dissipation vs Load Current; Vo =1.5 V (See Note A) Efficiency vs Load Current; Vin =48 V (See Note A) 100 12 10 90 VIN 8 Pd - Watts Efficiency - % VOUT 1.75V 1.5V 1.2V 1.05V 80 70 75.0V 60.0V 48.0V 36.0V 6 4 60 2 50 0 0 5 10 15 20 25 30 0 5 10 Iout (A) 15 20 25 30 Iout (A) Output Ripple vs Load Current; Vin =48 V (See Note A) Safe Operating Area; Vin =48 V (See Note B) 50 90 80 Ripple - mV VOUT 1.75V 1.5V 1.2V 1.05V 30 20 10 Ambient Temperature (°C) 40 Airflow 70 300LFM 200LFM 100LFM Nat conv 60 50 40 30 0 0 5 10 15 Iout (A) 20 25 30 20 0 5 10 15 20 25 30 Iout (A) Note A: All data listed in the above graphs has been developed from actual products tested at 25 °C. This data is considered typical data for the DC-DC Converter. Note B: SOA curves represent operating conditions at which internal components are at or below manufacturer’s maximum rated operating temperature. For technical support and more information, see inside back cover or visit www.ti.com PT4413—48 V 100-Watt 48-V Input Isolated DC/DC Converter PT4413 Specifications SLTS170C - JULY 2002 - REVISED JUNE 2003 (Unless otherwise stated, T a =25 °C, Vin =48 V, Vo =5.02 V, C o =0 µF, and I o =Io max) Characteristic Symbol Conditions Min PT4413 Typ Max Units Output Current Input Voltage Range Set Point Voltage Tolerance Temperature Variation Line Regulation Load Regulation Total Output Voltage Variation Io Vin Vo tol Regtemp Regline Regload ∆Votot Over Vin range Over Io Range 0 36 — — — — — 48 ±0.6 (1) ±0.8 ±2 ±1 20 75 — — — — A V %Vo %Vo mV mV — ±1.6 ±3 %Vo Efficiency Vo Ripple (pk-pk) Transient Response η Vr ttr ∆Vtr ITRIP OVP ƒo UVLO — — — — — — 250 — 92 70 75 ±2 28 125 300 32 — — — — — — 350 — % mVpp µs %Vo A %Vo kHz V 4.5 –0.2 — — — 0 1500 — 10 — — –0.3 2 1.4 Open (2) +0.8 — — — 5,000 — — — V Over-Current Threshold Output Over-Voltage Protection Switching Frequency Under-Voltage Lockout Remote On/Off Input Input High Voltage Input Low Voltage Input Low Current –40° >Ta > +85 °C Over Vin range Over Io range Includes set-point, line, load, –40° >Ta > +85 °C Io =15 A 20MHz bandwidth 1 A/µs load step, 50 % to 100 % Iomax Vo over/undershoot Shutdown, followed by auto-recovery Output shutdown and latch off Over Vin range Referenced to –Vin VIH VIL IIL Iin standby Cin Cout Standby Input Current Internal Input Capacitance External Output Capacitance Isolation Voltage Capacitance Resistance pins 1 & 2 connected Between +Vo and –Vo Input-output & input-case Input-output Input-output — 1200 — mA mA µF µF Vdc pF MΩ Notes: (1) If (–)Remote Sense is not used, pin 12 must be connected to pin 13 for optimum output voltage accuracy. (2) The Remote On/Off input has an internal pull-up. If it is left open-circuit the module will operate when input power is applied. A discrete MOSFET or bipolar transistor is recommended to control this input. The open-circuit voltage is typically 5 V. See application notes for interface considerations. PT4413 Characterstic Data Power Dissipation vs Load; VOUT =5.02 V (See Note A) Efficiency vs Load Current; V OUT =5.02 V (See Note A) 15 100 90 12 VIN 80 36.0V 48.0V 60.0V 75.0V 70 Pd - Watts Efficiency - % VIN 75.0V 60.0V 48.0V 36.0V 9 6 60 3 50 40 0 0 4 8 12 16 0 20 4 8 Iout - Amps Output Ripple vs Load Current; V OUT =5.02 V (See Note A) 16 20 Safe Operating Area; Vin =48 V (See Note B) 150 90 125 100 75.0V 60.0V 48.0V 36.0V 75 50 25 Ambient Temperature (°C) 80 VIN Ripple - mV 12 Iout - Amps Airflow 70 300LFM 200LFM 100LFM Nat Conv 60 50 40 30 0 20 0 4 8 12 16 20 0 Iout - Amps 4 8 12 16 20 Iout (A) Note A: All data listed in the above graphs has been developed from actual products tested at 25 °C. This data is considered typical data for the DC/DC converter. Note B: SOA curves represent operating conditions at which internal components are at or below manufacturer’s maximum rated operating temperature. For technical support and more information, see inside back cover or visit www.ti.com Application Notes PT4400/4410 Series Operating Features and System Considerations for the PT4400/PT4410 Series of DC/DC Converters Over-Current Protection To protect against load faults these converters incorporate output over-current protection. Applying a load to the output that exceeds the converter’s over-current threshold (see applicable specification) will cause the output voltage to momentarily fold back, and then shut down. Following shutdown the module will periodically attempt to automatically recover by initiating a soft-start power-up. This is often described as a “hiccup” mode of operation, whereby the module continues in the cycle of successive shutdown and power up until the load fault is removed. Once the fault is removed, the converter automatically recovers and returns to normal operation. Output Over-Voltage Protection Each converter incorporates protection circuitry that continually senses for an output overvoltage (OV) condition. The O V threshold automatically tracks the VID output voltage program setting to a level that is 25 % higher than that programmed at the control pins, VID0 through VID4. If the converter output voltage exceeds this 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 can only be done by momentarily removing the input power to the converter. For failsafe operation and redundancy, the O V 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 temperature of the converter’s metal case. If the case temperature exceeds a nominal 115 °C, the converter will shut down. The converter will then automatically restart when the sensed temperature drops back to approximately 105 °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. Under-Voltage Lockout The Under-Voltage Lock-Out (UVLO) is designed to prevent the operation of the converter until the input voltage is close to the minimum input voltage. The converter is held off when the input voltage is below the UVLO threshold, and turns on when the input voltage rises above the threshold. This prevents 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 converter will meet full specifications when the minimum specified input voltage is reached. The UVLO circuitry also overrides the operation of the Remote On/Off control. Only when the input voltage is above the UVLO threshold will the Remote On/Off control be functional. Primary-Secondary Isolation These converters incorporate electrical isolation between the input terminals (primary) and the output terminals (secondary). All converters are production tested to a withstand voltage of 1500VDC. This specification complies with UL60950 and EN60950 and the requirements for operational isolation. This allows the converter to be configured for either a positive or negative input voltage source. The data sheet ‘Pin Descriptions’ section provides guidance as to the correct reference that must be used for the external control signals. Input Current Limiting The converter is not internally fused. For safety and overall system protection, the maximum input current to the converter must be limited. Active or passive current limiting can be used. Passive current limiting can be a fast acting fuse. A 125-V fuse, rated no more than 10 A, is recommended. Active current limiting can be implemented with a current limited “Hot-Swap” controller. 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 specifications). The recommended direction for airflow is into, or perpendicular to, the longest side of the module’s metal case. See Figure 1. Figure 1 Recommended direction for airflow is into (perpendicular to) the longest side. For technical support and more information, see inside back cover or visit www.ti.com Application Notes PT4400/4410 Series For applications requiring output voltage On/Off control, these converters incorporate a “Remote On/Off” control (pin 1). This feature can be used to switch the module off without removing the applied input source voltage. The converter functions normally with Pin 1 open-circuit, providing a regulated output voltage when a valid source voltage is applied to +Vin (pins 4, 5), with respect to -Vin (pins 2, 3). When a low-level 1 ground signal is applied to pin 1, the converter output will be turned off. Figure 1 is an application schematic, which shows the typical use of the Remote On/Off function. Note the discrete transistor (Q1). The Remote On/Off pin has its own internal pull-up, allowing it to be controlled with an open-collector or open-drain device (See notes 2 & 3). Table 1 gives the threshold requirements. Table 2; UVLO Thresholds 4 Series Vin Range UVLO Threshold PT4400/4410 36 – 75 V 32V ±2 V Figure 1 + REMOTE SENSE +3.3V 21 +V s n s +V IN 4, 5 +V o u t +V i n 17–20 PT4401 –V IN 2, 3 Co –V i n -V o u t Remote On/Off Note 1 1 VID0 - VID4 7 8 9 10 11 Note 1 13–16 0V -V s n s 12 Q1 BSS138 1 =OFF L O A D + Using the Remote On/Off Function on the PT4400/PT4410 Series of DC/DC Converters – REMOTE SENSE PROGRAMMING PINS Vdd R1 10k U1a Note 1 When placed in the “Off” state, the standby current drawn from the input source is typically reduced to less than 1mA. Table 1; Pin 1 Remote On/Off Control Requirements Parameter 1 Min Typ Enable (V IH) 4.5 V — — Disable (VIL) — — 0.8 V Vo/c [Open-Circuit] Iin [pin 1 at –Vin] Max 5.0 V — — –0.5 mA Notes: 1. The Remote On/Off control uses –Vin (pins 2, 3) as its ground reference. All voltages are with respect to –Vin. 2. Use an open-collector device (preferably a discrete transistor) for the Remote On/Off input. A pull-up resistor is not necessary. To disable the output voltage, the control pin should be pulled low to less than +0.8 V. Turn-On Time: In the circuit of Figure 1, turning Q1 on applies a low-voltage to pin 1 and disables the converter output. Correspondingly, turning Q1 off allows pin 1 to be pulled high by an internal pull-up resistor. The converter produces a regulated output voltage within 50ms. Figure 2 shows the output response of a PT4401 following the turn-off of Q1. The turn off of Q1 corresponds to the drop in Q1 Vgs. Although the rise-time of the output voltage is short (<5 ms), the indicated delay time will vary depending upon the input voltage and the module’s internal timing. The output voltage of the PT4401 was set to 3.3 V by connecting VID0 (pin 7), VID2 (pin 9), and VID3 (pin 10) to the (–)Remote Sense (pin 12). The waveforms were measured with 48 VDC input voltage, and a 10 A resistive load. Figure 2 3. The Remote On/Off pin may be controlled with devices that have a totem-pole output. This is provided the output high-level voltage (VOH) meets the module’s minimum VIH specified in Table 1. Do not apply more than +20 V. If a TTL gate is used, a pull-up resistor may be required to the logic supply voltage. 4. The converter incorporates an “Under-Voltage Lockout” (UVLO). The UVLO keeps the converter off until the input voltage is close to the minimum specified operating voltage. This is regardless of the state of the Remote On/Off control. Table 2 gives the UVLO input voltage thresholds. Vo (1V/Div) Iin (1A/Div) Delay Time Q1 Vgs (10V/Div) HORIZ SCALE: 5ms/Div For technical support and more information, see inside back cover or visit www.ti.com Application Notes PT4400/4410 Series Pin-Coded Output Voltage Adjustment on the PT4400/4410 Series of DC/DC Converters input VID4 (pin 11) is internally disabled and is not functional. 6. If active devices are used to ground the voltage control pins, low-level open drain MOSFET devices should be used over bipolar transistors. The inherent Vce(sat) in bipolar devices introduces errors in the device’s internal voltage control circuit. Discrete transistors such as the BSS138 or IRLML2402 are examples of appropriate devices. These DC/DC converters have a programmable output voltage. In each case the desired output voltage must be selected from one of a number of discrete voltages using the voltage programming control pins. Depending on each model’s resolution and adjustment range, there are up to five control pins. They are identified VID0–VID4 (pins 7–11) respectively. By selectively strapping these control pins to (–)Remote Sense (pin 12), the output voltage can be programmed to one of up to 32 different values over the defined output voltage range. The program code and output voltage range of the PT4401/4411 is also compatible with the “Voltage ID” code defined in the Intel® VRM 8.2 specification. Refer to the applicable product specification sheet for the program code. Active Voltage Programming: Special precautions should be taken when making changes to the voltage progam code while the output is active. This activity induces a transient, which may activate the module’s output over-voltage (OV) protection. Once triggered the OV protection circuit latches the output off, and requires the momentary removal of input power to reset the module. OV protection trips can be avoided by limiting the output voltage adjustment to no more than a 15 % change from the initial voltage. Large transitions are best made with a series of incremental changes, allowing 100 µs settling time between each program state. When using active devices to program the output voltage, their state should be asserted prior to input power being applied. An alternative is to pull pin 1 (Remote On/Off) to -Vin (pins 2, 3) during the application of power, assert the required program code, and then release pin 1. The module will than initiate a soft-start power-up to the desired program voltage. Notes: 1. The programming convention is as follows:Logic 0: Connect to pin 12 (–Remote Sense). Logic 1: Open circuit/open drain (See notes 2, & 4) 2. Do not connect pull-up resistors to the voltage programming pins. 3. To minimize output voltage error, always use pin 12 (-Remote Sense) as the logic “0” reference. While -Vout (pins 13-16) can also be used for programming, doing so will degrade the voltage selection accuracy and load regulation of the product. 4. When VID0–VID4 are all open circuit (logic 1), the output voltage is undefined. In this state the output voltage of the converter cannot be guaranteed, and can vary with output load and input voltage. 5. On all models other than the PT4401/4411, the contol Figure 1 + REMOTE SENSE + VOUT 21 – V IN 4, 5 + V out + V in PT4400 2, 3 - V out 1 VID0 - VID4 7 8 9 L O A D Co – V in Remote On/Off INH 17–20 + + V IN + V sns 10 11 - V sns 13–16 – VOUT 12 Q1 BSS138 – REMOTE SENSE PROGRAMMING PINS For technical support and more information, see inside back cover or visit www.ti.com Application Notes PT4400/4410 Series PCB Dual Layout for PT4400/4410 and ¼–Brick Package Alternate Build Option The PCB footprint for the horizontal package versions (suffixes A & C) of the PT4400 and PT4410 series are dimensionally similar to a standard quarter-brick outline, making it easy to accommodate either package on the host PCB. This can provide the option for a second source, or in the case of the PT4400/4410 product, the added functionality of VID output voltage selection in a surface mount compatible package. Figure 4-1 shows an example of an alternate PCB layout that will accommodate the surface mount version of the PT product (package code ENP). It should be noted that Figure 4-1 is a dimensionless drawing and is offered only as a guide. Please refer to the respective package outline drawing and PCB layout recommendations for the products actually employed. As as an additional reference, Table 4-1 provides the pin-out for the PT4400/4410 series product. Table 4-1; PT4400/4410 Pin-Out Reference PT4400/4410 Pin Function 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Remote On/Off -Vin -Vin +Vin +Vin Pin Not Present VID 0 VID 1 VID 2 VID 3 VID 4 Sense (–) -Vout -Vout -Vout -Vout +Vout +Vout +Vout +Vout Sense (+) Figure 4-1; Example PCB Layout for PT4400/4410 and ¼–Brick Package Alternate Build 1 (1) 21 +Vout (8) +Sense(7) Adjust (6) –Sense(5) –Vout (4) +Vin (2) On/Off (3) –Vin ¼–Brick Outline PT4410 Outline – Component side – Alternate Layer – "¼–Brick" Reference For technical support and more information, see inside back cover or visit www.ti.com IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and applications using TI components. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information published by TI regarding third–party products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for such altered documentation. Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Following are URLs where you can obtain information on other Texas Instruments products & application solutions: Products Amplifiers Applications amplifier.ti.com Audio www.ti.com/audio Data Converters dataconverter.ti.com Automotive www.ti.com/automotive DSP dsp.ti.com Broadband www.ti.com/broadband Interface interface.ti.com Digital Control www.ti.com/digitalcontrol Logic logic.ti.com Military www.ti.com/military Power Mgmt power.ti.com Optical Networking www.ti.com/opticalnetwork Microcontrollers microcontroller.ti.com Security www.ti.com/security Telephony www.ti.com/telephony Video & Imaging www.ti.com/video Wireless www.ti.com/wireless Mailing Address: Texas Instruments Post Office Box 655303 Dallas, Texas 75265 Copyright 2003, Texas Instruments Incorporated