TPS7A8400RGRR - 3A Low-VIN Ultra-Low Noise LDO | Texas Instruments
Teilenummer: TPS7A8400RGRR ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $5.07 | $5,07 |
| 10 | $4.65 | $46,50 |
| 100 | $4.18 | $418,00 |
| 500 | $3.79 | $1.895,00 |
| 1.000 | $3.42 | $3.420,00 |
| 3.000 | $2.97 | $8.910,00 |
TPS7A8400RGRR Übersicht
An LDO (Low-Dropout) linear regulator is a type of voltage regulator that maintains a stable output voltage even when the input voltage is very close to the output voltage. Unlike switching regulators, LDOs add no switching noise to the output, making them ideal for powering noise-sensitive analog and RF blocks. Architecturally, LDOs sit between bulk DC-DC converters and downstream sensitive ICs in the power-tree hierarchy: switching regulator → LDO → analog/RF load. The TPS7A84 family is engineered specifically for high-current, low-noise analog rails where both high PSRR and high output current are simultaneously required.
Key differentiating features include an input voltage range of 1.4 V to 6.5 V (without BIAS) and a higher range with BIAS, an integrated open-drain power-good (PG) output for sequencing and fault monitoring, and a programmable soft-start (SS) pin for inrush-current control. The high PSRR effectively attenuates residual ripple from upstream switching converters, which is critical in multi-rail systems where switching noise would otherwise couple into precision analog paths.
Architecturally, the TPS7A8400 uses a precision bandgap reference and an advanced NMOS pass element that achieves both low dropout and high current. This combination enables point-of-load regulation for high-speed serializers/deserializers, RF transceivers, and FPGA core rails, where each load requires an isolated, low-noise supply. The high PSRR over a wide frequency range keeps supply-ripple-induced deterministic jitter low on clock and data paths.
Typical applications include powering FPGAs, ASICs, DSPs, high-speed ADCs/DACs, and RF transceivers in telecom, industrial, and test-and-measurement equipment. The wide output range supports both sub-1V core voltages for advanced CMOS devices and standard 3.3 V/5 V analog rails.
When designing in this part, place input and output ceramic capacitors as close as possible to the IC pins and follow TI's recommended capacitor types. The exposed thermal pad must be soldered to a sufficient copper pour to keep junction temperature within limits at 3-A continuous load.
Drop-in-Alternativen für TPS7A8400RGRR – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
TPS7A8400RGRT
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
TPS7A8401RGRR
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
TPS7A7200RGTR
✅ Drop-In ⚠️ Spezifikationen ungeprüft📋 Referenzalternative (nicht im Katalog)
LT3081
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MIC69502
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
TPS7A8400RGRR Grenzwerte & elektrische Eigenschaften
| Ausgangstyp | Adjustable/Programmable (pin-program) |
| Ausgangsspannungsbereich | 0.8 V to 5.0 V (adjustable), 0.8 V to 3.95 V (pin-programmable) |
| Maximaler Ausgangsstrom | 3 A |
| Input Voltage Range (without BIAS) | 1.4 V to 6.5 V |
| Dropout Voltage (max) | 180 mV at 3 A |
| Output Noise (0.8 V Vout) | 4.4 µVRMS |
| Output Noise (5.0 V Vout) | 7.7 µVRMS |
| Accuracy (line, load, temp) | 1% (max) |
| Power-Good-Ausgang | Yes (open-drain) |
| Soft-Start (SS) Pin | Yes (programmable) |
| Betriebstemperatur | -40 °C to +125 °C |
| Gehäuse | VQFN-20 (RGR) 3.5 × 3.5 mm with exposed thermal pad |
| Montageart | Surface Mount |
| MSL-Level | 2 (per JEDEC J-STD-020) |
| RoHS-Status | Compliant |
TPS7A8400RGRR Pin-Konfiguration
| Pin 1 | OUT — Regulated output voltage |
| Pin 2 | OUT — Regulated output voltage |
| Pin 3 | OUT — Regulated output voltage |
| Pin 4 | OUT — Regulated output voltage |
| Pin 5 | FB — Feedback input for adjustable mode |
| Pin 6 | PG — Power-good open-drain output |
| Pin 7 | SS — Soft-start programming pin |
| Pin 8 | NC — Not connected (per datasheet) |
| Pin 9 | NC — Not connected (per datasheet) |
| Pin 10 | EN — Enable input (active-high) |
| Pin 11 | BIAS — Optional BIAS supply input |
| Pin 12 | VIN — Input supply voltage |
| Pin 13 | VIN — Input supply voltage |
| Pin 14 | VIN — Input supply voltage |
| Pin 15 | GND — Ground |
| Pin 16 | GND — Ground |
| Pin 17 | GND — Ground |
| Pin 18 | GND — Ground |
| Pin 19 | PGND — Power ground (exposed pad region) |
| Pin 20 | PAD — Exposed thermal pad - connect to GND |
Typische Anwendungen
TPS7A8400RGRR ist geeignet für 7 Anwendungs: FPGA Core & SerDes Power Rail, RF Transceiver & PLL Power Supply, High-Speed ADC/DAC Analog Supply, Telecom & Networking Line Card Power, Test & Measurement Instrumentation, Industrial Automation & Motor Control, Automotive Infotainment & ADAS.
FPGA Core & SerDes Power Rail
The TPS7A8400RGRR's 3-A continuous output and 180 mV max dropout make it well suited to power low-voltage FPGA core and high-speed SerDes rails. The 4.4 µVRMS output noise and high PSRR over a wide frequency band minimize supply-induced deterministic jitter on multi-gigabit transceivers, while the small VQFN-20 (3.5 × 3.5 mm) footprint fits dense FPGA power trees. Place the regulator between a 5 V or 3.3 V intermediate bus and the FPGA VCCINT/VCCO pin with 22 µF ceramic input/output capacitors per the TI reference design. Compared to a switching post-regulator it dissipates more heat at large VIN-VOUT deltas, but adds no switching noise to the rail.
Empfohlen
RF Transceiver & PLL Power Supply
The TPS7A8400RGRR is ideal for powering RF transceivers, PLLs, and VCOs where supply noise directly translates into phase noise and reciprocal mixing artifacts. Its 4.4 µVRMS output noise (at 0.8 V) and high PSRR at low and mid frequencies prevent supply ripple from coupling into sensitive RF blocks. The 3-A current capability handles peak demands of multi-band radios and base-station front-ends, while the exposed thermal pad allows continuous 3-A operation in a compact area. Place the regulator adjacent to the RF IC AVDD pin with 10 µF X7R ceramics; unlike a switching regulator, the LDO introduces no spurious sidebands.
Empfohlen
High-Speed ADC/DAC Analog Supply
The TPS7A8400RGRR's 4.4 µVRMS output noise and 1% accuracy over line, load, and temperature make it an excellent point-of-load regulator for high-speed ADC and DAC analog rails. Low supply ripple preserves spurious-free dynamic range (SFDR) and signal-to-noise ratio (SNR) in precision converters sampling at 100 MSPS and above. The wide output range (0.8 V to 5.0 V adjustable, 0.8 V to 3.95 V pin-programmable) supports both 1.8 V and 3.3 V analog domains. Use a 5 V upstream switching regulator followed by the TPS7A8400 to combine high efficiency with low-noise analog performance.
Empfohlen
Telecom & Networking Line Card Power
In telecom and networking line cards, the TPS7A8400RGRR delivers clean, high-current power to PHY ICs, clocking devices, and high-speed serializers. The integrated open-drain power-good output enables sequenced startup across multiple rails, critical for multi-rail ASIC power-on requirements. The 1.4 V to 6.5 V input range (without BIAS) accommodates standard 3.3 V and 5 V intermediate bus voltages common in telecom backplanes. Combine with upstream POL switching regulators to balance efficiency and noise on densely populated line cards.
Empfohlen
Test & Measurement Instrumentation
Bench-top and rack-mounted test equipment demands ultra-low-noise analog rails to preserve measurement integrity. The TPS7A8400RGRR's 4.4 µVRMS noise and high PSRR isolate sensitive measurement front-ends from upstream switching noise. The 3-A output drives multi-channel digitizer ASICs and reference buffers, while the exposed thermal pad handles continuous full-load operation in enclosed instrument chassis. The programmable soft-start (SS) pin limits inrush when hot-plugging instrument modules into live backplanes.
Empfohlen
Industrial Automation & Motor Control
In industrial automation, the TPS7A8400RGRR powers precision analog front-ends, isolated ADC channels, and encoder interfaces for servo drives and PLCs. The wide -40 °C to +125 °C operating range and 1% accuracy over temperature ensure stable regulation in harsh factory environments. The 3-A capability also drives auxiliary analog rails in motion-control boards, while the open-drain PG output feeds back to the system MCU for fault handling. Place the regulator after an isolated DC-DC converter to provide local, low-noise regulation at the load.
Empfohlen
Automotive Infotainment & ADAS
Although the TPS7A8400RGRR is the commercial-grade variant, its high PSRR and low noise suit powering analog blocks in automotive infotainment head units and ADAS sensor boards. The 3-A output supports camera image signal processors and high-speed serializer power, while the small VQFN-20 footprint integrates into space-constrained PCBAs. For AEC-Q100 qualified requirements, designers should migrate to the TPS7A8400-Q1 automotive version; the commercial TPS7A8400RGRR itself is suitable for non-safety automotive subsystems.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für TPS7A8400RGRR – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | TPS7A8400RGRT | TPS7A8401RGRR | TPS7A7200RGTR | LT3081 | MIC69502 |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices | Microchip Technology |
| Package | VQFN-20 (RGR) 3.5x3.5 mm | VQFN-20 (RGR) - same | VQFN-20 (RGR) - same | VQFN-16 (RGT) - same family | VQFN-20 (RGR-class) - same | VQFN-20 (RGR-class) - same |
| Output Current | 3 A | 3 A | 3 A | 2 A | 1.5 A | 5 A |
Wichtigste Unterscheidungsmerkmale
- Highest output current in TPS7A84 family with sub-mW noise (vs. TPS7A7200RGTR)
- Pin-programmable plus adjustable output flexibility (vs. LT3081)
- Integrated power-good and programmable soft-start (vs. MIC69502)
Designhinweise
At 3 A continuous load and a typical VIN-VOUT differential of 1.5 V, the TPS7A8400RGRR dissipates approximately 4.5 W. Estimated: using the VQFN-20 (RGR) 3.5x3.5 mm package theta_JA of approximately 36 °C/W (per TI TPS7A84 datasheet thermal table), this yields a junction temperature rise of ~160 °C above ambient - so the exposed thermal pad MUST be soldered to at least 1 square inch of copper pour with thermal vias for reliable operation at full load. Add forced airflow or a top-side heatsink if the device is expected to run at 3 A in enclosed industrial environments with ambient > 60 °C.
Place input and output ceramic capacitors (typically 22 µF X7R) within 1-2 mm of the VIN and OUT pins respectively, with wide copper pours to minimize parasitic inductance. The exposed thermal pad should have an array of thermal vias (0.3 mm drill, 0.6 mm pitch) connecting top-side copper to internal ground planes to pull heat away from the die. Avoid routing high-frequency signal traces directly beneath the regulator to prevent noise coupling. Refer to the TI TPS7A84 datasheet land-pattern diagram for exact via placement.
Do not exceed the absolute maximum VIN of 7 V (without BIAS) - upstream transients on 5 V or 3.3 V rails during hot-plug events can damage the device if not clamped. Estimated: input TVS diodes (e.g., 6.5 V SMBJ) are recommended when the upstream source is hot-pluggable. Also, ensure the SS pin capacitor is populated (typically 10 nF to 100 nF) - leaving SS floating can cause unpredictable startup behavior and possible inrush damage to upstream capacitors.
The TPS7A8400RGRR's 4.4 µVRMS noise performance assumes the recommended capacitor types and layout per the TI TPS7A84 datasheet. Substituting lower-grade Y5V capacitors on the output degrades noise and load-transient performance. For applications where PSRR at 1 MHz matters (e.g., after a 1 MHz switching regulator), add a 10 µF + 0.1 µF parallel capacitor network on the output to extend PSRR into the higher frequency band.
Compliance-Informationen
RoHS and REACH compliant per TI product page. TPS7A8400RGRR is the commercial-grade (non-automotive) variant - migrate to TPS7A8400-Q1 for AEC-Q100 qualified automotive designs.
