ATH22T05 ASTEC | Alldatasheet

Document overview

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Technical content

Features

  • Up to 22 A Output Current
  • 5-V Input Voltage
  • Wide-Output Voltage Adjust (0.8 V to 3.6 V)
  • Efficiencies up to 96 %
  • 155 W/in³ Power Density
  • On/Off Inhibit
  • Output Voltage Sense
  • Pre-Bias Startup
  • Margin Up/Down Controls Rset = Resistor to set the desired output voltage (see spec. table for values). Cin = Required electrolytic 1,000 µF Cout = Optional 330 µF electrolytic
  • Auto-T rack™ Sequencing
  • Under-Voltage Lockout
  • Output Over-Current Protection (Non-Latching, Auto-Reset)
  • Over-T emperature Protection
  • Surface Mountable
  • Operating T emp: –40 to +85 °C
  • DSP Compatible Output Voltages
  • IPC Lead Free 2
  • Point-of-Load Alliance (POLA) Compatible Margin Up Margin Down VIN L O A D C IN 1,000 µF (Required) + C OUT 330 µF (Optional) Inhibit GND GND VOUT Vo Sense Track R SET (Required)

0.1 W, 1 %

(Top View) 10 9 8 543 Auto-Track™ Sequencing Pin Configuration Pin Function

1 GND

3 Inhibit *

7 GND

8 T rack

9 Margin Down *

10 Margin Up *

  • Denotes negative logic: Open = Normal operation Ground = Function active

Description

The ATH22T05 series of non-isolated power modules offers OEM designers a combination of high performance, small footprint, and industry leading features. As part of a new class of power modules these products provide designers with the flexibility to power the most complex multi-processor digital systems using off-the-shelf catalog parts. The series employs double-sided surface mount construction and provides high- performance step-down power conversion for up to 22 A of output current from a 5-V input bus voltage. The output volt- age of the ATH22T05 can be set to any value over the range, 0.8 V to 3.6 V , using a single resistor. This series includes Auto-T rack™. Auto-T rack simplifies the task of supply voltage sequencing in a power system by enabling modules to track each other, or any external voltage, during power up and power down. Other operating features include an on/off inhibit, output voltage adjust (trim), and margin up/down controls. T o ensure tight load regulation, an output voltage sense is also provided. A non-latching over-current trip and over-temperature shutdown provides load fault protection. T arget applications include complex multi-voltage, multi-processor systems that incorporate the industry’s high-speed DSPs, micro-processors and bus drivers. NOMINAL SIZE = 1.5 in x 0.87 in (38,1 mm x 22,1 mm) ATH22T05-9S REVISION 00 (3DEC2003)

North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Pin Descriptions Vin: The positive input voltage power node to the mod- ule, which is referenced to common GND. Vout: The regulated positive power output with respect to the GND node. GND: This is the common ground connection for the Vin and V out power connections. It is also the 0 VDC reference for the control inputs. Inhibit: The Inhibit pin is an open-collector/drain negative logic input that is referenced to GND. Applying a low- level ground signal to this input disables the module’ s output and turns off the output voltage. When the Inhibit control is active, the input current drawn by the regula- tor is significantly reduced. If the Inhibit pin is left open-circuit, the module will produce an output when- ever a valid input source is applied. Vo Adjust: A 0.1 W , 1 % tolerance (or better) resistor must be connected directly between this pin and pin 7 (GND) to set the output voltage to the desired value. The set point range for the output voltage is from 0.8 V to 3.6 V. The resistor required for a given output voltage may be calculated from the following formula. If left open circuit, the module output will default to its lowest output voltage value. For further information on output voltage adjustment consult the related application note. Rset = 10 k · 0.8 V – 2.49 k Vout – 0.8 V The specification table gives the preferred resistor values for a number of standard output voltages. Vo Sense: The sense input allows the regulation circuit to compensate for voltage drop between the module and the load. For optimal voltage accuracy V o Sense should be connected to V out. It can also be left disconnected. Track: This is an analog control input that enables the output voltage to follow an external voltage. This pin becomes active typically 20 ms after the input voltage has been applied, and allows direct control of the output voltage from 0 V up to the nominal set-point voltage. Within this range the output will follow the voltage at the Track pin on a volt-for-volt basis. When the control voltage is raised above this range, the module regulates at its set-point voltage. The feature allows the output voltage to rise simultaneously with other modules pow- ered from the same input bus. If unused, the input may be left unconnected. Note: Due to the under-voltage lockout feature, the output of the module cannot follow its own input voltage during power up. For more information, consult the related application note. Margin Down: When this input is asserted to GND, the output voltage is de creased by 5% from the nominal. The input requires an open-collector (open-drain) interface. It is not TTL compatible. A lower percent change can be accomodated with a series resistor. For further infor- mation, consult the related application note. Margin Up: When this input is asserted to GND, the output voltage is increased by 5%. The input requires an open-collector (open-drain) interface. It is not TTL compatible. The percent change can be reduced with a series resistor. For further information, consult the related application note.

Ordering Information

ATH22T05 Series —5-V Input 22-A, 5-V I nput Non-Isolated Wide-Output Adjust Power Module REVISION 00 (3DEC2003) Input Voltage Output Voltage Output Current Model Number 4.5V to 5.5V 0.8V 1 to 3.6V 22A ATH22T05-9(S)(J) Options: “-J” - Through-hole T ermination, T ray Packaging “-SJ” - SMT T ermination, T ray Packaging “-S” - SMT T ermination, T&R Packaging Notes: 1Preset output voltage is 0.8V; externally adjustable to 3.6V through the Vo,Adjust pin

North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Environmental & Absolute Maximum Ratings (Voltages are with respect to GND) Characteristics Symbols Conditions Min Typ Max Units T rack Input Voltage V track –0.3 — V in + 0.3 V Operating T emperature Range T a Over Vin Range –40 — 85 °C Solder Reflow T emperature T reflow Surface temperature of module body or pins 215 (i) °C Storage T emperature T s — –40 — 125 °C Mechanical Shock Per Mil-STD-883D, Method 2002.3 — 500 — G’s1 msec, ½ Sine, mounted Mechanical Vibration Mil-STD-883D, Method 2007.2 —2 0— G ’ s20-2000 Hz Weight — — 7 — grams Flammability — Meets UL 94V-O Notes: (i) During reflow of SMD package version do not elevate peak temperature of the module, pins or internal components above the st ated maximum. For further guidance refer to the application note, “Reflow Soldering Requirements for Plug-in Power Surface Mount Products.” Specifications (Unless otherwise stated, T a =25 °C, V in =5 V, Vout =3.3 V , Cin =1,000 µF, Cout =0 µF, and Io =Iomax) PTH05020W Characteristics Symbols Conditions Min Typ Max Units Output Current I o 60 °C, 200 LFM airflow 0 — 22 (1) A25 °C, natural convection 0 — 22 (1) Input Voltage Range V in Over Io range 4.5 — 5.5 V Set-Point Voltage T olerance V o tol R SET=698 Ω ——± 2 (2) %Vo T emperature Variation ∆Regtemp –40 °C <Ta < +85 °C — ±0.5 — %V o Line Regulation ∆Regline Over Vin range — ±5 — mV Load Regulation ∆Regload Over Io range — ±5 — mV T otal Output Variation ∆Regtot Includes set-point, line, load, ——± 3 (2) %VoRSET =698Ω , –40 °C ≤ Ta ≤ +85 °C Efficiency η Io =10 A R SET = 698 Ω Vo = 3.3 V — 96 — RSET = 2.21 kΩ Vo = 2.5 V — 94 — RSET = 4.12 kΩ Vo = 2.0 V — 93 — %RSET = 5.49 kΩ Vo = 1.8 V — 92 — RSET = 8.87 kΩ Vo = 1.5 V — 91 — RSET = 17.4 kΩ Vo = 1.2 V — 90 — RSET = 36.5 kΩ Vo = 1.0 V — 88 — Vo Ripple (pk-pk) V r 20 MHz bandwidth — 20 — mVpp Over-Current Threshold I o trip Reset, followed by auto-recovery — 41 — A T ransient Response 1 A/µs load step, 50 to 100 % I omax, Cout =330 µF ttr Recovery Time — 70 — µSec ∆Vtr Vo over/undershoot — 120 — mV Margin Up.Down Adjust ∆Vo margin — ± 5 — % Margin Input Current (pins 9 /10) I IL margin Pin to GND — – 8 (3) —µ A T rack Input Current (pin 8) I IL track Pin to GND — — –130 (4) µA T rack Slew Rate Capability dV track/dt Vtrack – Vo ≤ 50 mV and Vtrack < Vo(nom) 5 — — V/ms Under-Voltage Lockout UVLO V in increasing — 4.3 4.5 VVin decreasing 3.1 3.7 — Inhibit Control (pin3) R eferenced to GND Input High Voltage V IH Vin –0.5 — Open (4) V Input Low Voltage VIL –0.2 — 0.8 Input Low Current IIL inhibit Pin to GND — –130 — µA Input Standby Current I in inh Inhibit (pin 3) to GND, T rack (pin 8) open — 10 — mA Switching Frequency ƒ s Over Vin and Io ranges 250 300 340 kHz External Input Capacitance C in 1,000 (5) ——µ F External Output Capacitance C out 0 330 (6) 20,000 µF Reliability MTBF Per Bellcore TR-332 4.9 — — 10 6 Hrs50 % stress, Ta =40 °C, ground benign Notes: (1) See SOA curves or consult factory for appropriate derating. (2) The set-point voltage tolerance is affected by the tolerance and stability of R SET. The stated limit is unconditionally met if R SET has a tolerance of 1 %, with 200 ppm/°C or better temperature stability. (3) A small low-leakage (<100 nA) MOSFET is recommended to control this pin. The open-circuit voltage is less than 1 Vdc. (4) This control pin has an internal pull-up to the input voltage Vin. If it is left open-circuit the module will operate when i nput power is applied. A small low-leakage (<100 nA) MOSFET is recommended for control. For further information, consult the related application note. (5) A 1,000 µF electrolytic input capacitor is required for proper operation. The capacitor must be rated for a minimum of 700 m Arms of ripple current. (6) An external output capacitor is not required for basic operation. Adding 330 µF of distributed capacitance at the load will improve the transient response. ATH22T05 Series —5-V Input 22-A, 5-V I nput Non-Isolated Wide-Output Adjust Power Module

North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 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. Derating limits apply to modules soldered directly to a 4 in. × 4 in. double-sided PCB with 1 oz. copper. Typical Characteristics Characteristic Data; Vin =5 V (See Note A) Efficiency vs Load Current Power Dissipation vs Load Current Output Ripple vs Load Current Safe Operating Area; Vin =5 V (See Note B) Output Voltage =3.3 V ATH22T05 Series—5-V Input 22-A, 5-V I nput Non-Isolated Wide-Output Adjust Power Module 0 5 10 15 20 Iout (A) Ambient Temperature (°C) 400LFM 200LFM 100LFM Nat Conv Airflow 100 0 4 8 1 21 62 0 Iout - Amps Efficiency - % 3.3 V 2.5 V 1.8 V 1.5 V 1.2 V 1 V VOUT 0 4 8 12 16 20 Iout - Amps Vout - mV 2.5 V 1.8 V 3.3 V 1.5 V 1.2 V 1 V VOUT 0 4 8 12 16 20 Iout - Amps Pd - Watts

North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Adjusting the Output Voltage of the ATH22T033 & ATH22T05 Wide-Output Adjust Power Modules The Vo Adjust control (pin 4) sets the output voltage of the ATH22T033 and ATH22T05 products. The ad- justment range of the ATH22T033 (3.3-V input) is from 0.8 V to 2.5 V 1, and the ATH22T05 (5-V input) from 0.8 V to 3.6 V . The adjustment method requires the addi- tion of a single external resistor, Rset, that must be connected directly between the Vo Adjust and GND pins 2. T able 1-1 gives the preferred value of the external resistor for a num- ber of standard voltages, along with the actual output voltage that this resistance value provides. For other output voltages the value of the required resistor can either be calculated using the following formula, or simply selected from the range of values given in T able 1-2. Figure 1-1 shows the placement of the required resistor. Rset = 10 kΩ · 0.8 V – 2.49 kΩVout – 0.8 V Figure 1-1; Vo Adjust Resistor Placement Notes: 1. Modules that operate from a 3.3-V input bus should not be adjusted higher than 2.5 V . 2. Use a 0.1 W resistor. The tolerance should be 1 %, with temperature stability of 100 ppm/°C (or better). Place the resistor as close to the regulator as possible. Connect the resistor directly between pins 4 and 7 using dedicated PCB traces. 3. Never connect capacitors from V o Adjust to either GND or Vout. Any capacitance added to the Vo Adjust pin will affect the stability of the regulator. PTH05020W C OUT 330µF GND VOUT VO Sense [Note 3] VO AdjGND VO Sense VOUT R SET

0.800 Open

0.825 318 k Ω 0.850 158 k Ω 0.875 104 k Ω 0.900 77.5 k Ω 0.925 61.5 k Ω 0.950 50.8 k Ω 0.975 43.2 k Ω 1.000 37.5 k Ω 1.025 33.1 k Ω 1.050 29.5 k Ω 1.075 26.6 k Ω 1.100 24.2 k Ω 1.125 22.1 k Ω 1.150 20.4 k Ω 1.175 18.8 k Ω 1.200 17.5 k Ω 1.225 16.3 k Ω 1.250 15.3 k Ω 1.275 14.4 k Ω 1.300 13.5 k Ω 1.325 12.7 k Ω 1.350 12.1 k Ω 1.375 11.4 k Ω 1.400 10.8 k Ω 1.425 10.3 k Ω 1.450 9.82 k Ω 1.475 9.36 k Ω 1.50 8.94 k Ω 1.55 8.18 k Ω 1.60 7.51 k Ω 1.65 6.92 k Ω 1.70 6.4 k Ω 1.75 5.93 k Ω 1.80 5.51 k Ω 1.85 5.13 k Ω 1.90 4.78 k Ω 1.95 4.47 k Ω Vout (Standard) R set (Pref’d Value) V out (Actual) 3.3 V 2 698 Ω 3.309V 2.5 V 2.21 k Ω 2.502 V 2 V 4.12 k Ω 2.010 V 1.8 V 5.49 k Ω 1.803 V 1.5 V 8.87 k Ω 1.504 V 1.2 V 17.4 k Ω 1.202 V 1 V 36.5 k Ω 1.005 V 0.8 V Open 0.8 V Table 1-1; Preferred Values of R set for Standard Output Voltages ATH22T033 & ATH22T05 Series Table 1-2; Output Voltage Set-Point Resistor Values Va Req’d R set Va Req’d R set 2.00 4.18 k Ω 2.05 3.91 k Ω 2.10 3.66 k Ω 2.15 3.44 k Ω 2.20 3.22 k Ω 2.25 3.03 k Ω 2.30 2.84 k Ω 2.35 2.67 k Ω 2.40 2.51 k Ω 2.45 2.36 k Ω 2.50 2.22 k Ω 2.55 2.08 k Ω 2.60 1.95 k Ω 2.65 1.83 k Ω 2.70 1.72 k Ω 2.75 1.61 k Ω 2.80 1.51 k Ω 2.85 1.41 k Ω 2.90 1.32 k Ω 2.95 1.23 k Ω 3.00 1.15 k Ω 3.05 1.07 k Ω 3.10 988 Ω 3.15 914 Ω 3.20 843 Ω 3.25 775 Ω 3.30 710 Ω 3.35 647 Ω 3.40 587 Ω 3.45 529 Ω 3.50 473 Ω 3.55 419 Ω 3.60 367 Ω ATH22T05-9S

North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Table 2-1: Input/Output Capacitors ATH22T033/T05: Capacitor Recommendations Input Capacitor The recommended input capacitor(s) is determined by the 1,000 µF (1) minimum capacitance and 700 mArms minimum ripple current rating. Ripple current and <100 m Ω equivalent series resistance (ESR) values are the major considerations, along with temperature, when designing with different types of capacitors. T antalum capacitors have a recommended minimum voltage rating of 2 × (the maximum DC voltage + AC ripple). This is standard practice for tantalum capacitors to insure reliability. Ceramic Capacitors Ceramic capacitors may be substituted for electrolytic types using the minimum capacitance, for improved ripple reduction on the input bus. Output Capacitors (Optional) The recommended ESR of the capacitors is equal to or less than 150 m Ω . Electrolytic capacitors have marginal ripple performance at frequencies greater than 400 kHz but excellent low frequency transient response. Above the ripple frequency, ceramic capacitors are necessary to improve the transient response and reduce any high frequency noise components apparent during higher current excursions. Preferred low ESR type capacitor part numbers are identified in T able 2-1. Tantalum Capacitors T antalum type capacitors can be used for the output, but only the AVX TPS, Sprague 593D/594/595or Kemet T495/T510 series. These capacitors are recommended over many other tantalum types due to their higher rated surge, power dissipation, and ripple current capability. As a caution the TAJ series by AVX is not recommended. This series has considerably higher ESR, reduced power dissipation, and lower ripple curr ent capability. The TAJ series is less reliable than the AVX TPS series when determining power dissipation capability. T antalum, ceramic, or Os-con types are recommended for applica- tions where ambient temperatures fall below 0 °C. Capacitor Table T able 2-1 identifies the characteristics of capacitors from a number of vendors with acceptable ESR and ripple current (rms) ratings. The number of capacitors required at both the input and output buses is identified for each capacitor type. This is not an extensive capacitor list. Capacitors from other vendors are available with comparable specifications. Those listed are for guidance. The RMS ripple current rating and ESR (at 100kHz) are critical parameters necessary to insure both optimum regulator performance and long capacitor life. /rodneVroticapaC seireS scitsiretcarahCroticapaCy titnauQ gnikroW egatloV )Fµ(eulaVt nelaviuqE)RSE( ecnatsiseRseireS mumixaMC°501 elppiR )smrI(tnerruC lacisyhP )mm(eziS tupnI suB tuptuO suB rebmuNtraProdneV cinosanaP )laidaR(CF KF) .tMecafruS( V01 V01 V52 V01 065 0001 0001 0001 090.0 Ω 860.0 Ω 0600 Ω 080.0 Ω Am557 Am0501 Am0011 Am058 01 × 5.21 01 × 61 5.21 × 5.31 01 × 2.01 165A1CFUEE 201A1CFUEE Q201E1KFVEE P201A1KFVEE noc-imehCdetinU ).tMecafruS(AXP XF seireSZXL V3.6 V3.6 V01 V01 074 0001 086 0001 020.0 Ω 310.0 Ω 090.0 Ω 860.0 Ω Am0314 Am5394 Am067 Am0501 01 × 7.7 01 × 5.01 01 × 5.21 01 × 61 )1(2 PT08JM174CV3.6AXP M0001XF6 LL21X01M186BV01ZXL LL61X01M201BV01ZXL nocihciN seireSMP V3.6 V01 V61 0001 0001 0001 350.0 Ω 560.0 Ω 550.0 Ω Am0301 Am0601 Am0044 5.21x01 61 × 51 01 × 01 RPM201J0DHU 6HPM201A1MPU 6HHM201C1MPU :noc-sO-oynaS PS ).tMecafruS(PVS V01 V01 074 065 510.0 Ω 310.0 Ω Am0054> Am0025> 01 × 5.01 01 × 7.21 )1(2 M074PS01 M065PVS01 mulatnaTXVA ).tMecafruS(SPT V01 V01 074 074 540.0 Ω 060.0 Ω Am3271 Am6281 L3.7 × W7.5 × H1.4 )1(2 )1(2 5400R010M774ESPT 0600R010M774VSPT remyloPtemeK mulatnaT seireS035T/025T ).tMecafruS( V01 V01 033 033 040.0 Ω 510.0 Ω Am0081 Am0083> W3.4 × L3.7 × H0.4 SA010M733X025T SA010M733X035T mulatnaTeugarpS seireSD595 ).tMecafruS( V010 740 01.0 Ω Am0441L 2.7 × W6 × H1.4 )1(21 T 2R0100X774D595 ATH22T033 & ATH22T05 Series (1) T otal capacitance of 940 µF is acceptable based on the combined ripple current rating.

ATH Series of Wide-Output Adjust Power Modules (3.3/5-V Input) North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Features of the ATH Family of Non-Isolated Wide Output Adjust Power Modules Point-of-Load Alliance The ATH family of non-isolated, wide-output adjust power modules are optimized for applications that require a flexible, high performance module that is small in size. These products are part of the “Point-of-Load Alliance” (POLA), which ensures compatible footprint, interoperability and true second sourcing for cust omer design flexibility. The POLA is a collaboration between T exas Instruments, Artesyn T echnologies, and Astec Power to offer customers advanced non-isolated modules that provide the same functionality and form factor. Prod- uct series covered by the alliance includes the ATH06 (6 A), ATH10 (10 A), ATH12/15 (12/15 A), ATH18/22 (18/22 A), and the ATH26/30 (26/30 A). From the basic, “Just Plug it In” functionality of the 6-A modules, to the 30-A rated feature-rich ATH30 Series, these products were designed to be very flexible, yet simple to use. The features vary with each product. T able 3-1 provides a quick reference to the available features by product and input bus voltage. Table 3-1; Operating Features by Series and Input Bus Voltage For simple point-of-use applications, the ATH06 (6A) provides operating features such as an on/off inhibit, output voltage trim, pre-bias startup (3.3/5-V input only), and over-current protection. The ATH10 (10 A), and ATH12/15 (12/15 A) include an output voltage sense, and margin up/down controls. Then the higher output current, ATH18/22 (18/22A) and ATH26/30 (26/30A) products incor- porate over-temperature shutdown protection. All of the products referenced in T able 3-1 include Auto-T rack™. Power-Up Characteristics When configured per their standard application all the ATH products will produce a regulated output voltage fol- lowing the application of a valid input source voltage. All the modules include soft-start circuitry. This slows the initial rate in which the output voltage can rise, thereby limiting the amount of in-rush current that can be drawn from the input source. The soft-start circuitry also introduces a short time delay (typically 5 ms-10 ms) into the power-up characteristic. This delay is from the point that a valid input source is recognized, to the initial rise of the output voltage. Figure 3-1 shows the power-up characteristic of the 22-A output product (ATH22T05-9xx), operating from a 5-V input bus and configured for a 3.3-V output. The wave- forms were measured with a 5-A resistive load. The initial rise in input current when the input voltage first starts to rise is the charge current drawn by the input capacitors. Figure 3-1 Vo (2V/Div) Iin (2A/Div) Vin (5V/Div) HORIZ SCALE: 10ms/Div Over-Current Protection For protection against load faults, all modules incorporate output over-current protection. Applying a load that exceeds the regulator’s over-current threshold will cause the regulated output to shut down. Following shutdown a module will periodically attempt 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. Series Input Bus I OUT

12 V 6 A  

Adjust (Trim) Thermal Shutdown Pre-Bias Startup Margin Up/Down Auto-Track™ This is a feature unique to the ATH family, and was specifically designed to simplify the task of sequencing the supply voltage in a power system. These and other features are described in the following sections. ATH10 ATH06 ATH12/15 ATH18/22 ATH26/30 10 A

ATH Series of Wide-Output Adjust Power Modules (3.3/5-V Input) North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Figure 3-5; Simultaneous Power Up with Auto-Track Control PTH05010W Track VIN VO GNDInhibit PTH05020W Track VIN VO GNDInhibit

7 COUT

Vo2 =2V Vo1 =3.3V +5V On/Off Control 1 = Power Down 0 = Power Up BSS138 0.047µF 100k 698 4k12 Figure 3-4; Sequenced Power Up & Power Down Using Auto-Track Figure 3-6; Simultaneous Power Down with Auto-Track Control Vo1 (1V/Div) Vo2 (1V/Div) On/Off Input (5V/Div) HORIZ SCALE: 5ms/Div Vo1 (1V/Div) Vo2 (1V/Div) On/Off Control (5V/Div) HORIZ SCALE: 5ms/Div ATH22T05-9SJ ATH15T05-9SJ

ATH Series of Wide-Output Adjust Power Modules (3.3/5-V Input) North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Margin Up/Down Controls The ATH10 (10A), ATH12/15 (12/15A), ATH18/22 (18/ 22A) and ATH26/30 (26/30A) products incorporate Margin Up and Margin Down control inputs. These controls allow the output voltage to be momentarily adjusted 1, either up or down, by a nominal 5 %. This provides a convenient method for dynamically testing the operation of the load circuit over its supply margin or range. It can also be used to verify the function of supply voltage supervisors. The ±5 % change is applied to the adjusted output voltage, as set by the external resistor, Rset at the Vo Adjust pin. The 5 % adjustment is made by pulling the appropriate margin control input directly to the GND terminal 2. A low-leakage open-drain device, such as an n-channel MOSFET or p-channel JFET is recommended for this purpose 3. Adjustments of less than 5 % can also be accom- modated by adding series resistors to the control inputs (See Figure 3-4). The value of the resistor can be selected from T able 3-2, or calculated using the following formula. Up/Down Adjust Resistance Calculation T o reduce the margin adjustment to something less than 5 %, series resistors are required (See R D and R U in Figure 3-7). For the same amount of adjustment, the resistor value calculated for R U and R D will be the same. The formulas is as follows. RU or RD = 499 – 99.8 k Ω ∆% Where ∆ % = The desired amount of margin adjust in percent. Notes: 1. The Margin Up* and Margin Dn* controls were not intended to be activated simultaneously. If they are their affects on the output voltage may not completely cancel, resulting in the possibility of a slightly higher error in the output voltage set point. 2. The ground reference should be a direct connection to the module GND at pin 7 (pin 1 for the ATH06). This will produce a more accurate adjustment at the load circuit terminals. The transistors Q 1 and Q2 should be located close to the regulator. 3. The Margin Up and Margin Dn control inputs are not compatible with devices that source voltage. This includes TTL logic. These are analog inputs and should only be controlled with a true open-drain device (preferably a discrete MOSFET transistor). The device selected should have low off-state leakage current. Each input sources 8 µA when grounded, and has an open-circuit voltage of 0.8 V . Figure 3-7; Margin Up/Down Application Schematic Table 3-2; Margin Up/Down Resistor Values % Adjust R U / RD 5 0.0 k Ω 4 24.9 k Ω 3 66.5 k Ω 2 150.0 k Ω 1 397.0 k Ω Cout +Cin VIN GND MargDn L O A D +VOUT MargUp +Vo RD RU PTH05010W (Top View) 10 9 8 543 GND RSET

ATH Series of Wide-Output Adjust Power Modules (3.3/5-V Input) North America (USA): 1-888-41-ASTEC Europe (UK): 44(1384)842-211 Asia (HK): 852-2437-9662 Pre-Bias Startup Capability Only selected products in the ATH family incorporate this capability. Consult T able 3-1 to identify which products are compliant. A pre-bias 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 com- plex 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 ATH family of power modules incorporate synchro- nous rectifiers, but will not sink current during startup or whenever the Inhibit pin is held low. However, to ensure satisfactory operation of this function, certain conditions must be maintained.

2 Figure 3-7 shows an application

demonstrating the pre-bias startup capability. The start- up waveforms are shown in Figure 3-9. Note that the output current from the ATH15T033-9xx (I o) shows neg- ligible current until its output voltage rises above that backfed through diodes D 1 and D2. Note: The pre-bias start-up feature is not compatible with Auto-Track. When the module is under Auto-Track control, it is fully active and will sink current if the output voltage is below that of a back-feeding source. Therefore 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 using the Inhibit pin. The latter allows Auto-Track’s internal (RC) voltage ramp to rise above the set-point voltage. Notes 1. Startup is the relatively short period (approx. 10 ms) prior to the output voltage rising. The startup period immediately follows either the application of a valid input source v oltage, or the release of a ground signal at the Inhibit pin. 2. T o 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-T rack 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 V in through a 1-k Ω resistor. Vo = 2.5 V VIN = 3.3 V 2k21 1k0 ASIC VCORE VCCIO Io PTH03010W Track VIN VO GNDInhibit Vadj Sense CIN 330 µF D1, D2 MBR3100 COUT 330 µF Figure 3.8; Application Circuit Demonstrating Pre-Bias Startup Vin (1 V/Div) Vo (1 V/Div) Io (5 A/Div) HORIZ SCALE: 5 ms/Div Figure 3.9; Pre-Bias Startup Waveforms ATH15T033-9S