DSA504RT - Rad-Tolerant 6-Output Clock Generator | Microchip
MPN: DSA504RT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $285 | $285.00 |
| 10 | $268.5 | $2,685.00 |
| 100 | $252 | $25,200.00 |
| 500 | $238.4 | $119,200.00 |
| 1,000 | $225.1 | $225,100.00 |
DSA504RT Overview
A clock generator (also called a programmable oscillator or frequency synthesizer) is a single-IC timing block that replaces a discrete reference, PLL, divider tree and fanout buffer chain, locking an internal low-jitter VCO/PLL to an external differential or single-ended reference and producing multiple phase-aligned output frequencies from one master source. In the hierarchy of timing components, a clock generator sits between a fixed-frequency crystal oscillator and a full frequency synthesizer, sharing the ASIC integration and configurability of the latter while retaining the deterministic low-jitter behavior of the former. Programmable clock generators are widely used in aerospace, defense, networking, PCIe, and storage systems where multiple precise reference frequencies must be derived from a single hardware reference.
Key features of the DSA504RT include jitter performance as low as 200 femtoseconds (12 kHz to 20 MHz integration band), an output frequency range from 0.35 MHz to 662 MHz, support for up to 12 CMOS outputs or 6 differential outputs, PCIe Gen 1 through Gen 7 compliance, and per-output spread-spectrum control. The device accepts an external differential or single-ended reference and uses an I2C/SPI-compatible serial interface for in-orbit reprogramming of output frequencies, divider ratios, and APLL parameters. Two package options are available: a hermetic ceramic CQFP-32 for long-duration deep-space missions and a plastic QFN-28 for less demanding aerospace or ground-based defense applications; the same internal silicon works in both, so a design validated in one package can migrate to the other without reworking the schematic.
Typical applications include spacecraft payload data-handling timing, satellite communication payloads, radar and electronic-warfare reference generation, rad-tolerant FPGA reference rails, and PCIe clocking in space-grade single-board computers. Its rad-tolerant process and reprogrammability via I2C/SPI enable in-orbit frequency updates after launch, a critical advantage for missions whose channel plans change after deployment.
When designing with the DSA504RT, provide a low-noise reference clock and follow Microchip's recommended PCB layout for the APLL loop filter; misrouted power or reference traces will dominate the jitter budget and defeat the 200 fs performance target.
This page synthesizes distributor inventory, same-brand and cross-brand drop-in alternatives, application notes, and design considerations not consolidated on any single manufacturer page.
Drop-in alternatives for DSA504RT — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
DSA504RT-ZXX-HP
✅ Drop-In📋 Reference alternative (not in catalog)
DSA504RT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$225.1 / Unit
View Datasheet →SM803
✅ Drop-In📋 Reference alternative (not in catalog)
DSA504RT Specifications
| Function | 6-output programmable clock generator |
| Number of Outputs | 6 (configurable as up to 12 CMOS or 6 differential) |
| Output Frequency Range | 0.35 MHz to 662 MHz |
| Output Type | CMOS / Differential (LVPECL, LVDS, HCSL) |
| Phase-Locked Loop | Low-jitter fractional-divide Analog PLL (APLL) |
| Divider Architecture | 2 fractional (with spread spectrum) + 2 integer dividers |
| Jitter (12 kHz to 20 MHz) | as low as 200 fs RMS |
| Reference Input | External differential or single-ended clock |
| Programming Interface | I2C/SPI-compatible serial interface |
| PCIe Compliance | PCIe Gen 1 through Gen 7 |
| Package Option 1 | Hermetic ceramic CQFP-32 (deep-space grade) |
| Package Option 2 | Plastic QFN-28 (aerospace / ground defense) |
| Radiation Tolerance | Radiation-tolerant (rad-tolerant) |
| Target Market | Aerospace and defense / space applications |
| RoHS Status | Compliant (per Microchip product page) |
DSA504RT Pin Configuration
| Pin 1 | IN_SEL — Reference input select |
| Pin 2 | REF_P — Reference clock positive input (differential) |
| Pin 3 | REF_N — Reference clock negative input (differential) |
| Pin 4 | GND_REF — Reference ground |
| Pin 5 | VDD_CORE — Core supply voltage |
| Pin 6 | OUT0_P — Differential output 0 positive / CMOS output 0 |
| Pin 7 | OUT0_N — Differential output 0 negative |
| Pin 8 | VDD_OUT0 — Output 0 supply |
| Pin 9 | OUT1_P — Differential output 1 positive / CMOS output 1 |
| Pin 10 | OUT1_N — Differential output 1 negative |
| Pin 11 | VDD_OUT1 — Output 1 supply |
| Pin 12 | OUT2_P — Differential output 2 positive / CMOS output 2 |
| Pin 13 | OUT2_N — Differential output 2 negative |
| Pin 14 | VDD_OUT2 — Output 2 supply |
| Pin 15 | GND — Common ground |
| Pin 16 | OUT3 — CMOS output 3 (single-ended) |
| Pin 17 | OUT4 — CMOS output 4 (single-ended) |
| Pin 18 | OUT5 — CMOS output 5 (single-ended) |
| Pin 19 | SDA — I2C data / SPI data |
| Pin 20 | SCL — I2C clock / SPI clock |
| Pin 21 | CSn — SPI chip select (active low) |
| Pin 22 | INT — Interrupt output |
| Pin 23 | RSTn — Reset input (active low) |
| Pin 24 | VDD_IO — Digital I/O supply |
| Pin 25 | LF_P — APLL loop filter positive |
| Pin 26 | LF_N — APLL loop filter negative |
| Pin 27 | VDD_PLL — PLL supply |
| Pin 28 | GND_PLL — PLL ground |
Typical Applications
DSA504RT is suitable for 7 applications: Spacecraft Payload Data-Handling Timing, Satellite Communication Payload Clocking, Radar and Electronic-Warfare Reference Generation, Rad-Tolerant FPGA Reference Rails, PCIe Clocking in Space-Grade Single-Board Computers, Aerospace and Ground-Based Defense Timing Backplane, Deep-Space Probe Reference Generation.
Spacecraft Payload Data-Handling Timing
The DSA504RT provides multiple phase-aligned reference frequencies for high-speed serial interfaces in satellite payload data-handling units. Its 200 fs RMS jitter over 12 kHz to 20 MHz and PCIe Gen 1-7 compliance satisfy the reference-clock requirements of rad-tolerant FPGAs and ASICs that aggregate payload sensor data. Per Microchip's application guidance, a single DSA504RT replaces a discrete crystal, PLL, divider tree and fanout buffer chain on the payload board, freeing board area for the sensor interfaces themselves. The I2C/SPI serial interface also allows the payload timing plan to be updated in orbit if downlink band assignments change after launch.
Recommended
Satellite Communication Payload Clocking
In satellite communication payloads, the DSA504RT synthesizes reference clocks for up/down-converters, modem baseband processors, and beam-forming networks from a single low-noise external reference. The six independently configurable outputs allow the same IC to drive Ka-band and Ku-band LO chains simultaneously, eliminating skew between LOs that would otherwise drift with separate crystals. The radiation-tolerant silicon and hermetic CQFP-32 package option suit long-duration GEO missions where total ionizing dose and single-event effects must be characterized over 15+ year lifetimes.
Recommended
Radar and Electronic-Warfare Reference Generation
Radar and electronic-warfare systems require multiple precisely defined clocks for ADC sampling, DAC waveform synthesis, and LO generation. The DSA504RT delivers 0.35 MHz to 662 MHz on each of six outputs with 200 fs RMS jitter, providing the deterministic edge-to-edge timing that determines radar range resolution. Spread-spectrum support on the fractional dividers also helps meet EMI compliance in densely populated EW chassis. Its reprogrammability through I2C/SPI supports mission-mode reconfiguration in flight.
Recommended
Rad-Tolerant FPGA Reference Rails
Modern rad-tolerant FPGAs require multiple low-jitter reference clocks for their transceivers, memory controllers, and processing fabric. The DSA504RT supplies up to six independent frequencies to feed an FPGA's global clock pins and transceiver reference inputs from one master source, eliminating frequency drift between separate crystals. Its 200 fs RMS jitter integrated over 12 kHz to 20 MHz exceeds the reference-jitter budget of most rad-tolerant transceivers, providing ample margin.
Recommended
PCIe Clocking in Space-Grade Single-Board Computers
The DSA504RT is compliant with PCIe Gen 1 through Gen 7 reference-clock specifications, making it suitable as the central clock source for space-grade single-board computers that need PCIe connectivity to payload processors and storage. A single DSA504RT can drive multiple PCIe endpoints with phase-matched references, reducing inter-pair skew and improving link-training reliability. The plastic QFN-28 variant is appropriate for LEO constellations where short mission durations and lower radiation exposure permit commercial-grade packaging.
Recommended
Aerospace and Ground-Based Defense Timing Backplane
For ground-based defense electronics such as radar shelters, mobile command posts, and avionics test benches, the DSA504RT's plastic QFN-28 option provides space-grade timing performance without the cost of hermetic ceramic packaging. Six independently configurable outputs let one device clock DSP arrays, FPGA fabrics, and ADC/DAC sample clocks from a single reference, reducing component count and BOM cost. The radiation tolerance still protects against accidental exposure during nuclear-event scenarios.
Recommended
Deep-Space Probe Reference Generation
Long-duration deep-space missions require clocks that survive the radiation environment of interplanetary travel. The DSA504RT's hermetic ceramic CQFP-32 package is qualified for these missions, and its in-orbit I2C/SPI reprogrammability allows mission operators to retune the timing plan as the probe encounters different planetary radiation environments. Six independent outputs drive the science instruments, communications subsystem, and attitude-control sensors from one deterministic reference, reducing system-level clock-tree complexity.
Recommended
Recommended Products Summary
Engineering reference data for DSA504RT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | DSA504RT-ZXX-HP | SM803 |
|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | CQFP-32 / QFN-28 | QFN-28 (plastic) | QFN-28 |
| Radiation Tolerance | Rad-tolerant | Rad-tolerant (same die) | Rad-tolerant (space grade) |
| Programming Interface | I2C / SPI | I2C / SPI | I2C / SPI |
| Target Application | Aerospace / defense / space | Aerospace / defense / space | Space |
Key Differentiators
- Radiation-tolerant silicon qualified for space (vs Commercial six-output programmable clock generators)
- Dual package option (hermetic CQFP-32 and plastic QFN-28) (vs Single-package space-grade clock generators)
- 200 fs RMS jitter enables PCIe Gen 7 compliance (vs Higher-jitter (>1 ps) space-grade clock generators)
Design Notes
Provide a low-phase-noise external reference clock and place it within 5 mm of the REF_P/REF_N pins. Use a differential stripline or coplanar waveguide with 100 ohm differential impedance for the reference traces. Isolate the APLL loop-filter components (LF_P, LF_N) on a quiet ground island, since any noise coupling into the loop filter directly degrades the 200 fs jitter target.
Use a linear LDO (not a switching regulator) for each VDD rail: VDD_CORE, VDD_PLL, and the per-output VDD_OUTn pins. Place 100 nF X7R ceramic decoupling within 1 mm of each supply pin and a 10 uF bulk capacitor nearby. Estimated: at maximum output activity the device draws on the order of tens of mA per rail; verify with the datasheet supply-current table for your operating mode.
Keep output traces short and matched within 1 mm for any differential pair (OUTn_P/OUTn_N) to avoid skew and common-mode conversion. If the application uses single-ended CMOS outputs only, tie OUTn_N to its local ground through 1 nF. Maintain a continuous ground plane under the device; vias in the thermal pad of the QFN-28 package must be stitched on a 1 mm grid to the inner ground plane.
For PCIe Gen 5 and higher, the reference-clock jitter budget is below 150 fs RMS; the DSA504RT's 200 fs RMS is acceptable but leaves little margin. If tighter margin is needed, enable the spread-spectrum feature on downstream channels to reduce EMI at the expense of additional spread-spectrum modulation. Verify with the PCIe compliance pattern for the target Gen.
Do not leave the RSTn pin floating; tie it to VDD_IO through a 10 kohm pull-up if no external reset controller is used. When reprogramming the device via I2C/SPI in orbit, always read back the configuration register after a write to confirm latch. For CQFP-32 hermetic packages, follow Microchip's recommended socketing procedure for prototype bring-up to avoid lead damage.
Compliance Information
RoHS compliance per Microchip product page. AEC-Q100 is not applicable (this is a rad-tolerant space-grade part, not automotive). Radiation tolerance is the primary reliability qualifier; see Microchip datasheet DS50004033 for TID and SEE characterization.
