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Switching Power Supply (SPS) Design Bill of Materials (BOM) for (Launch Vehicle 2b) LV2b

Below are SPS Design Schematic Revisions:

LV2b SPS Design Schematic Revisions:

Note[1]: Unless specified otherwise in the components's description, all caps are ceramic and resistors are thin or thick film. All components are surface mount technology (SMT) components. Most component packages are 0805 packages. Also all components which are not calculated/specified as of yet will be given descriptions of "TBD".

Note[2]: RoHS Compliant Convention in the component description:

• If a component is RoHS Compliant ==> "RoHS Compliant"
• If a component is not RoHS Compliant ==> "RoHS Non-Compliant"
• If it is unkown ==> "RoHS Compliant???"

Since we will be using leaded solder, we can use parts with or without lead so being RoHS compliant is not critical.

Note[3]: There are some components (0805) which are possibly available from PSAS's current inventory, if not, the components will either be listed under the sub-heading "Choices:" or will be listed alone if there is only one choice.

Note[4]: This BOM is with respect to revision rev2_2 of the SPS_Design_Schematics listed above. All reference designators which did not change from the previous LV2 SPS design schematic as is specified in the SPS Design Notes in pages 3 - 31, are kept the same. All new reference designators in the new LV2b SPS Design schematic will have the number "5" as the second digit. These designators will become permenant after the final design review.

Note[5]: There are three IC's in this design: LT1767EMS8, MAX5902AAETT and TLV3012AIDBVT from Linear Technology, Maxim-IC and Texas Instruments respectively.

Note[6]: Nearly all parts can be ordered from Digikey. If Digikey does not have it in stock then a link to the component's datasheet is included in the component description and would need to be directly ordered from the vendor and/or another manufacturer/distributor.

Note[7]: The component reference designators in this BOM are listed in alpha/numerical order.

Step-Down Switching Voltage Regulator (Buck Topology) (U200)

• Main SPS Switching Buck Regulator at +3.3V rail and Io,max ~ 400 mA
• Monolithic Step-Down Buck Switching Regulator, Current Mode Control, 1.5 A, 1.25 MHz (Adjustable), 3V < Vin < 25 V, 8-MSOP (No exposed ground/thermal pad), RoHS Non-Compliant, Linear Technology, LT1767EMS8 (Digikey p/n LT1767EMS8-ND $6.00/1)

Inductors:

Split Buck Inductor (L200a, L200b)

• L200a, L200b
  • SD3118-470-R Low Profile Power Inductor 47 uH, Shielded Drum Package (Bobbin), RoHS Compliant???, Tape and Reel
  • The SD3118-470-R datasheet from Coiltronics.

Power Bus Input Choke (L201, L202)

• L201, L202
  • CMS1-11-R Common Mode Inductors 100 uH, Micro-PAC Plus Package, RoHS Compliant, Tape and Reel.
  • The CMS1-11-R datasheet from Coiltronics.

Capacitors:

Buck Output Cap (C200)

• 22 uF, 6.3 V, 0805, X5R, Cut Tape, RoHS Compliant, Panasonic - ECG , ECJ-2FB0J226M (Digikey p/n PCC2401CT-ND $8.31/10)
• Datasheet.

Buck Input Cap (C201)

• 10 uF, 25 V, 1206, X5R, Cut Tape, RoHS Compliant, Panasonic-ECG, ECJ-3YB1E106K (Digikey p/n PCC2414CT-ND $5.45/10)
• Datasheet.

Boost Cap (C202)

• 0.1 uF, 50 V, 0805, X7R, Cut Tape, RoHS Compliant, Panasonic-ECG, ECJ-2YB1H104K (Digikey p/n PCC1840CT-ND $1.61/10)
• Datasheet.
• NOTE: PSAS has this part in its inventory.

Power Bus Input Caps (C203, C204)

• C203
  • 22 uF, 25 V, Tant, T491 Series, 7343-31 (EIA), Cut Tape, RoHS Compliant???, Kemet, T491D226K025AT (Digikey p/n 399-3782-1-ND $0.65/1)
  • Datasheet.
• C204
  • 0.33 uF, 50 V, 0805, X7R, Cut Tape, RoHS Compliant, Murata Electronics North America , GRM219R71H334KA88D (Digikey p/n 490-3327-1-ND $3.09/10)
  • Datasheet.

LT1767 Frequency Compensation Caps (C205, C206)

• C205
  • TBD
• C206
  • TBD

LT1767 FB Resistor Network Shunt Caps (C208, C209)

• C208:
  • TBD
• C209:
  • 10 pF, 50 V, 0805, NPO, Cut Tape, RoHS Compliant???, BC Components, VJ0805A100JXACW1BC (Digikey p/n BC1256CT-ND $0.52/10)
  • Datasheet.

LT1767 UVLO Resistor Network Shunt Cap (C210)

• 0.1 uF, 50 V, 0805, X7R, Cut Tape, RoHS Compliant???, BC Components , VJ0805Y104KXATW1BC (Digikey p/n BC1298CT-ND $0.72/10)
• Datasheet.

TLV3012AIDBVT "Secondary Power Supply" Cap (C250)

• 2.7 uF, 10 V, 0805, X5R, Cut Tape, RoHS Compliant, Kemet, C0805C275K8PACTU (Digikey p/n 399-3127-1-ND $7.02/10)
• datasheet.

TLV3012AIDBVT Overvoltage Detection Cap (C251)

• 0.015 uF, 100 V, 0805, X7R, Cut Tape, RoHS Compliant, AVX Corporation, 08051C153KAT2A (Digikey p/n 478-1359-1-ND $2.64/10)
• The Datasheet.

SPS Secondary Buck Output Cap (C252)

• TBD
• Note: This is an application specific cap whose value is mostly independent from the SPS design.

Diodes:

Buck (Catch) Schottky Diode (CR200)

• 30 V, 1.5 A, 4 ns, New MiniPower 2P, Cut Tape, RoHS Compliant???, Panasonic - SSG, MA2Q70500L (Digikey p/n MA2Q70500LCT-ND $0.83/1)
• Datasheet.
• NOTE: PSAS has this part in its inventory.

Boost Rectifier Diode (CR201)

• 180 V, 0.6 A, SOT-23, Cut Tape, RoHS Compliant, Micro Commercial Co., MMBD1501-TP (Digikey p/n MMBD1501TPMSCT-ND $2.00/10)
• Datasheet.

TLV3012AIDBVT "Secondary Power Supply" Schottky Diode (CR250)

• 30 V, 1.5 A, 4 ns, New MiniPower 2P, Cut Tape, RoHS Compliant???, Panasonic - SSG, MA2Q70500L (Digikey p/n MA2Q70500LCT-ND $0.83/1)
• Datasheet.
• NOTE: PSAS has this part in its inventory.

SPS Secondary Buck (Catch) Schottky Diode (CR251)

• 30 V, 1.5 A, 4 ns, New MiniPower 2P, Cut Tape, RoHS Compliant???, Panasonic - SSG, MA2Q70500L (Digikey p/n MA2Q70500LCT-ND $0.83/1)
• Datasheet.
• NOTE: PSAS has this part in its inventory.

SPS Output Power On LED (D201)

• 1.9 V, 90 mcd @ 20 mA, 609 nm, 0805, Orange Diffused LED, CML Innovative Technologies Inc, CMDA5BA7D1S (Digikey p/n L71515CT-ND $3.00/10)
• Datasheet.

Discrete Components:

Power Bus Fast-Acting Fuse (F200)

• 500 mA, 50 V, 1206, Fast Acting Short Time Lag, RoHS Compliant, Wickmann USA Inc, FCD120500TP (Digikey p/n WK6213CT-ND $0.56/1)
• Datasheet.

MAX5902 External P-MOSFET (Q250)

• -60 V, -3 A, SOT-23-6, P-Channel MOSFET, Cut Tape, RoHS Compliant, Zetex Inc, ZXMP6A17E6TA (Digikey p/n ZXMP6A17E6CT-ND $1.04/1)
• Datasheet.

TLV3012AIDBVT External Logic-Level N-MOSFET (Q251)

• 100 V, 170 mA, RDS(on) = 10 ohm @ Vgs = 4.5V, SOT-23, Cut Tape, RoHS Compliant???, N-Channel Logic-Level MOSFET, Infineon Technologies, BSS123E6327 (Digikey p/n BSS123INCT-ND $0.36/1)
• Datasheet.

Power Bus Input Voltage Suppressor (TVS200)

• 18 V, SMB, Unidirectional, Cut Tape, RoHS Non-Compliant, Diodes Inc, SMBJ18A-13 (Digikey p/n SMBJ18ADICT-ND $0.89/1)
• Datasheet.
• NOTE: PSAS has this part in its inventory.

Overcurrent/Circuit-Breaker Protection (U250)

• MAX5902 +72 V, SOT-23, Simple Swapper How-Swap Controller. Note: The MAX5902AAETT will be used.
• Datasheet.
• NOTE: Ordered 5 samples from vendor.

Undervoltage/Overvoltage Protection (U251)

• Nanopower Push-Pull Output Comparator with Voltage Reference, 1.8 V < Vin < 5.5 V, SOT-23-6, Tape & Reel (TR), RoHS Compliant, Texas Instruments, TLV3012AIDBVT (Digikey p/n 296-16830-2-ND $262.50/250)
• Datasheet.
• NOTE: Ordered 5 samples from vendor.

Resistors:

LT1767 FB Resistor Network: (R200, R201)

• R200:
  • 10.0 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF1002 (Digikey p/n RHM10.0KCCT-ND $0.38/10)
  • Datasheet.
• R201:
  • 17.4 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF1742 (Digikey p/n RHM17.4KCCT-ND $0.38/10)
  • Datasheet.

LT1767EMS8 Frequency Compensation Resistor (R206)

• TBD

LT1767EMS8 UVLO Lockout Resistor Network: (R209, R210)

• R209
  • 60.4 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF6042 (Digikey p/n RHM60.4KCCT-ND $0.38/10)
  • Datasheet.
• R210
  • 10.0 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF1002 (Digikey p/n RHM10.0KCCT-ND $0.38/10)
  • Datasheet.

SPS Output Power On LED Current Limiter Resistor (R214)

• 649 ohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant, Rohm, MCR10EZHF6490 (Digikey p/n RHM649CCT-ND $0.38/10)
• Datasheet.

DC Path From SPS Node GND to Chassis GND Resistor (R215)

• 100 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant, Rohm, MCR10EZHF1003 (Digikey p/n RHM100KCCT-ND $0.38/10)
• Datasheet.

MAX5902 Circuit-Breaker Resistor Network (R250, R251)

• R250
  • 61.9 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF6192 (Digikey p/n RHM61.9KCCT-ND $0.38/10)
  • Datasheet.
• R251
  • 10.0 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF1002 (Digikey p/n RHM10.0KCCT-ND $0.38/10)
  • Datasheet.

MAX5902AAETT Circuit-Breaker External P-MOSFET RDS(on) Additional Series Resistor (R252)

• 0.82 ohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Panasonic - ECG, ERJ-6RQFR82V (Digikey p/n P.82DCT-ND $2.10/10)
• Datasheet.
• Note: This value may change due to board level testing results.

TLV3012AIDBVT Overvoltage Detection External N-MOSFET Current Limiting Resitor (R253)

• 47.0 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF4702 (Digikey p/n RHM47.0KCCT-ND $0.38/10)
• Datasheet.

TLV3012AIDBVT UVLO Lockout Resistor Network (R254, R255)

• R254
  • 18.2 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF1822 (Digikey p/n RHM18.2KCCT-ND $0.38/10)
  • Datasheet.
• R255
  • 10.0 kohm, 0805, 1%, 1/8 W, Cut Tape, RoHS Compliant???, Rohm, MCR10EZHF1002 (Digikey p/n RHM10.0KCCT-ND $0.38/10)
  • Datasheet.

Digikey BOM

NOTE: Component fields with a "-" mean they are TBD.

Coiltronics BOM

NOTE: The CMS1-11-R (L201,L202) is available from Newark InOne but with a 40 day lead time!

NOTE: Component fields with a "-" mean they are TBD.

Total SPS Component Count = 40

SPS LV2b Design Notes

SPSDesignNotes

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Attachments:

• SPS Design Schematic rev0.pdf
• SPS Design Schematic rev1.pdf
• SPS Design Schematic rev2.pdf
• SPS Design Schematic rev2 1.pdf
• SPS Design Schematic rev2 2.pdf