My Inquiry
My Account
Texas Instruments LM20146MHX/NOPB
- Part No.:
- LM20146MHX/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- 16-PowerTSSOP (0.173", 4.40mm Width)
- Datasheet:
-
LM20146MHX/NOPB.pdf
- Description:
- IC REG BUCK ADJ 6A 16HTSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,350
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM20146MHX/NOPB from Texas Instruments is a 6A synchronous buck regulator with adjustable switching frequency (250–750 kHz), integrated 16mΩ/20mΩ FETs, and precision 0.8V feedback reference. It delivers stable point-of-load regulation for FPGA, ASIC, and DSP core supplies from 2.95V–5.5V input rails.
For engineers reviewing the LM20146MHX/NOPB datasheet, LM20146MHX/NOPB pinout, LM20146MHX/NOPB application, or LM20146MHX/NOPB equivalent, key selection criteria include pre-biased startup capability, peak current mode control with nonlinear slope compensation, soft-start/tracking dual-function pin, and thermal shutdown at 160°C.
Technical Context
The LM20146MHX/NOPB implements peak current mode control with parabolic slope compensation to maintain stability across output voltages from 0.8V to VIN−0.5V. Its internal 2.7V VCC regulator powers analog circuitry, while AVIN/AGND separation isolates bias supply noise from power-switching grounds.
It integrates overvoltage protection (108% of VFB), PGOOD open-drain output with 16µs deglitch, and precision enable with 1.18V turn-on threshold and 66mV hysteresis. The SS/TRK pin supports both capacitor-controlled soft-start and external voltage tracking without pulling down pre-biased outputs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Current | 6A continuous - supports high-current digital loads without external current-sense resistors |
| Input Voltage Range | 2.95V to 5.5V - compatible with standard 3.3V and 5V system buses |
| Feedback Reference | 0.8V ±1.5% - enables precise low-voltage core rail generation (e.g., 1.2V, 1.5V) via resistor divider |
| Switching Frequency | 250 kHz to 750 kHz - set by RT-to-ground resistor; higher frequencies allow smaller inductors |
| High-Side RDS(on) | 20 mΩ max at 3.5A - reduces conduction loss and thermal stress at full load |
| Low-Side RDS(on) | 16 mΩ max at 3.5A - improves efficiency in synchronous rectification mode |
| Current Limit Threshold | 7.35A to 9.35A - factory-trimmed for consistent inductor sizing across temperature |
| Soft-Start Time | Adjustable via external capacitor on SS/TRK - prevents input inrush and ensures monotonic startup |
Pinout & Package
LM20146MHX/NOPB uses a 16-pin HTSSOP package with exposed thermal pad (EP), optimized for PCB heat dissipation without heatsinks.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SS/TRK | Soft-start or tracking control input | 5 µA internal current source charges external capacitor; overrides FB reference if driven below 800 mV |
| FB | Feedback input to error amplifier | Connects to resistor divider; regulates output when voltage = 0.8V ±1.5% |
| PGOOD | Open-drain power-good indicator | Pulls low when VOUT deviates >6% from target; requires 10–100 kΩ pull-up |
| COMP | External compensation node | Connect RC network to stabilize loop; supports ceramic, polymer, or electrolytic output capacitors |
| PVIN | Main input power for switches (pins 6,7) | Must be tied together and bypassed with low-ESR capacitor near package |
| SW | Switch node (pins 8,9) | Drives external inductor; high dv/dt node requiring careful layout and snubber if needed |
| PGND | Power ground for switches (pins 10,11) | Separate from AGND; connects to input/output capacitor ground planes |
| EN | Precision enable input | Turns on at 1.18V typical; hysteresis prevents chatter during brownout conditions |
| VCC | Internal 2.7V sub-regulator output | Bypass with 1 µF ceramic capacitor; powers internal logic and gate drivers |
| AVIN | Analog supply input | Must connect to PVIN through RC filter to reduce noise coupling into error amplifier |
| AGND | Analog ground reference | Quiet return for FB, COMP, EN, RT; must be isolated from PGND except at single-point star ground |
| RT | Frequency adjust input | Resistor to ground sets oscillator frequency; 49.9 kΩ → ~750 kHz, 249 kΩ → ~260 kHz |
| NC | No-connect (pin 5) | Must be connected to GND for proper operation per datasheet |
| EP | Exposed thermal pad | Electrically weakly tied to GND; solder to PCB ground plane for optimal thermal performance |
Key Features
| Feature | Design Value |
|---|---|
| Pre-biased startup support | Prevents output sinking during multi-rail power sequencing - avoids damage to FPGA/ASIC I/O structures |
| Nonlinear slope compensation | Parabolic ramp adapts to output voltage level - eliminates need for manual slope tuning across VOUT range |
| Integrated OVP, UVLO, thermal shutdown | Self-contained fault protection - no external monitoring IC required for basic system reliability |
| Diode emulation mode | Disables reverse inductor current at light loads - maintains >85% efficiency down to 100 mA |
| Adjustable soft-start & tracking | Single pin (SS/TRK) configures either monotonic ramp or coordinated rail sequencing - simplifies multi-supply designs |
| 97% peak efficiency | Achieved at 5V→1.2V/6A with 1µH inductor - minimizes board-level thermal management requirements |
Applications
| FPGA Core Supply | DSP I/O Rail Regulation |
|---|---|
Use Scenario: Powering Xilinx or Intel FPGA core logic operating at 1.0V–1.2V from a 3.3V or 5V backplane. IC Role / Device Role / Timing Role: Primary synchronous buck regulator delivering up to 6A with tight transient response and pre-bias tolerance. Use Value: Enables reliable hot-plug and rail-sequencing compliance without external tracking ICs or discrete MOSFETs. | Use Scenario: Generating clean 1.8V or 2.5V I/O supply for TI C6000 or Analog Devices SHARC DSPs. IC Role / Device Role / Timing Role: Secondary buck converter synchronized to main core rail using SS/TRK pin for voltage tracking. Use Value: Ensures I/O voltage ramps monotonically after core voltage - prevents latch-up and bus contention during startup. |
| ASIC Memory Interface | Optical Transceiver Bias |
Use Scenario: Supplying DDR3/DDR4 memory termination and interface rails (VTT, VREF) in networking ASICs. IC Role / Device Role / Timing Role: High-efficiency point-of-load regulator with <1% output ripple and fast load-step recovery. Use Value: Maintains signal integrity under dynamic memory access patterns - reduces bit-error rate in high-speed SerDes links. | Use Scenario: Providing stable 3.3V bias for SFP+/QSFP optical modules in telecom infrastructure equipment. IC Role / Device Role / Timing Role: Compact, thermally robust DC-DC stage replacing linear regulators to minimize power density and heat buildup. Use Value: Delivers 97% efficiency at full load - extends module thermal margin and supports fanless chassis design. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS54620RGYT | 6A rating, 3.5V–17V input, fixed 600kHz frequency, no SS/TRK tracking function | Lacks voltage tracking; requires external circuitry for rail coordination | Preferred where wide-input range is needed but tracking is unnecessary |
| MP2315GJ-Z | 6A rating, 4.5V–28V input, 500kHz fixed frequency, no PGOOD or thermal shutdown | Missing integrated fault protection and power-good signaling | Suitable for cost-sensitive industrial applications with external supervision |
Compared with TPS54620RGYT and MP2315GJ-Z, LM20146MHX/NOPB uniquely combines pre-biased startup, SS/TRK tracking, and full fault protection in a 2.95V–5.5V input range - making it optimal for tightly sequenced, low-voltage digital systems where reliability and rail coordination are critical.
Availability
LM20146MHX/NOPB is available at Aetrix Electronics and suitable for FPGA core supplies, DSP I/O regulation, ASIC memory interfaces, and optical transceiver biasing requiring stable component supply and long-term production continuity.
Supply support for LM20146MHX/NOPB includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies with broad industrial and automotive qualification.
The LM20146MHX/NOPB belongs to TI's high-performance synchronous buck regulator product line, designed specifically for low-voltage, high-current point-of-load applications in FPGA, ASIC, and DSP power architectures.
FAQ
What is the minimum input voltage required for LM20146MHX/NOPB to operate?
The LM20146MHX/NOPB has an absolute minimum input voltage of 2.95V per its operating ratings. Below this, the internal UVLO circuit disables switching to prevent unstable operation. The typical UVLO turn-on threshold is 2.7V with 45mV hysteresis, ensuring robust start-up from noisy 3.3V rails. This makes LM20146MHX/NOPB ideal for systems powered directly from regulated 3.3V sources without intermediate LDOs.
Does LM20146MHX/NOPB support startup into a pre-biased output?
Yes, LM20146MHX/NOPB fully supports pre-biased startup: when the output voltage is non-zero at enable, the device will not sink current or pull the rail low. Instead, it waits until the SS/TRK voltage exceeds the FB pin voltage before initiating switching. This behavior protects downstream FPGA/ASIC I/O structures from reverse current damage during multi-rail sequencing - a confirmed feature documented in the "Pre-Bias Start up Capability" section of the SNVS563C datasheet.
How is the switching frequency set on LM20146MHX/NOPB?
The switching frequency of LM20146MHX/NOPB is set by connecting a resistor between the RT pin and ground. A 49.9 kΩ resistor yields ~750 kHz (typ), while 249 kΩ yields ~260 kHz (typ). The relationship is inverse and nonlinear due to internal oscillator design; exact values are specified in the Electrical Characteristics table. No external clock signal or programming interface is required - frequency adjustment is purely resistor-based and stable across temperature.
What is the purpose of the AVIN and AGND pins on LM20146MHX/NOPB?
The AVIN and AGND pins on LM20146MHX/NOPB provide a dedicated low-noise analog supply path for the error amplifier, reference, and modulation circuitry. AVIN must be connected to PVIN through an RC filter (e.g., 10Ω + 1µF) to attenuate switch-node noise, while AGND serves as the quiet return for FB, COMP, EN, and RT. Separating analog and power grounds prevents coupling of high di/dt currents into sensitive control loops - a requirement explicitly called out in the "PIN DESCRIPTIONS" and "OPERATION DESCRIPTION" sections of the datasheet.
Can LM20146MHX/NOPB be used without an external compensation network on the COMP pin?
No - LM20146MHX/NOPB requires an external RC network on the COMP pin for loop stability. The device uses transconductance error amplification, and compensation is not internal. While some configurations may appear stable with minimal components, the datasheet specifies that stability depends on output capacitor ESR, inductance, and load; proper compensation (typically a series RC from COMP to AGND) is mandatory for guaranteed performance across all operating conditions. Skipping compensation risks oscillation or poor transient response.
LM20146MHX/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 16-PowerTSSOP (0.173", 4.40mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2.95V
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- 0.8V
- Voltage - Output (Max):
- 4.68V
- Current - Output:
- 6A
- Frequency - Switching:
- 260kHz ~ 750kHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-HTSSOP
LM20146MHX/NOPB FAQ
1.How can I place an order for LM20146MHX/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM20146MHX/NOPB on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LM20146MHX/NOPB reliable?
The price and inventory of LM20146MHX/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM20146MHX/NOPB is usually 5 days.
3.What payment methods are accepted for LM20146MHX/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM20146MHX/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM20146MHX/NOPB?
LM20146MHX/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM20146MHX/NOPB order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LM20146MHX/NOPB?
For technical support, including LM20146MHX/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM20146MHX/NOPB requirements.
6.How does Aetrix verify that LM20146MHX/NOPB is sourced from the original manufacturer or authorized distributors?
All LM20146MHX/NOPB products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LM20146MHX/NOPB meets industry standards.
7.What is the process for return or replacement of LM20146MHX/NOPB?
All LM20146MHX/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM20146MHX/NOPB, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LM20146MHX/NOPB part is unused and in its original packaging.
Return procedure for LM20146MHX/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM20146MHX/NOPB Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
