Texas Instruments LM20136MH/NOPB

Overview

LM20136MH/NOPB from Texas Instruments is a 6A synchronous buck regulator with peak current mode control, operating from 2.95V–5.5V input and delivering adjustable output down to 0.8V. It integrates 16mΩ low-side and 20mΩ high-side MOSFETs, supports frequency synchronization up to 1.5 MHz, and features pre-bias startup-used in FPGA, ASIC, and DSP power rails.

For engineers reviewing the LM20136MH/NOPB datasheet, LM20136MH/NOPB pinout, LM20136MH/NOPB application, or LM20136MH/NOPB equivalent, key selection considerations include its 410 kHz default switching frequency, soft-start/tracking dual-function SS/TRK pin, integrated OVP/UVLO/thermal shutdown, and HTSSOP-16 exposed-pad thermal performance.

Technical Context

The LM20136MH/NOPB implements peak current mode control with nonlinear (parabolic) slope compensation-dynamically adjusted per output voltage to ensure stability across 0.8V–5V VOUT range. Its internal 2.7V sub-regulator powers bias circuitry via VCC, while AVIN/AGND provide isolated analog supply and ground for error amplifier precision.

Switching is synchronized via SYNC pin (500 kHz–1.5 MHz), with automatic fallback to ~410 kHz if SYNC is grounded. The device enters diode emulation mode below critical conduction boundary and skips pulses at very light loads (<100 mA) to maintain efficiency.

Key Specifications

Pinout & Package

LM20136MH/NOPB uses a 16-pin HTSSOP package with exposed thermal pad (EP), optimized for surface-mount thermal dissipation on 4-layer PCBs (θJA = 25°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck regulator applications.

Compared with TPS54620RGYT and MP2315DJ-LF-Z, the LM20136MH/NOPB uniquely combines 2.95–5.5 V input compatibility, pre-bias startup, SS/TRK tracking, and 410 kHz default frequency-making it optimal for tightly sequenced, low-voltage digital power in FPGA/ASIC platforms.

Availability

LM20136MH/NOPB is available at Aetrix Electronics and suitable for FPGA core power, DSP I/O supply, ASIC memory interface, optical transceiver bias, and multi-rail embedded systems requiring stable component supply and long-term production continuity.

Supply support for LM20136MH/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 decades of expertise in high-reliability power conversion ICs.

The LM20136MH/NOPB belongs to TI's high-current synchronous buck regulator product line, designed specifically for low-voltage, high-efficiency point-of-load power delivery in FPGA, DSP, and ASIC applications demanding precise sequencing and robust fault protection.

FAQ

What is the minimum recommended output voltage for LM20136MH/NOPB?

The LM20136MH/NOPB supports an adjustable output voltage down to 0.8 V, set by the feedback resistor divider connected to the FB pin. This 0.8 V reference is trimmed to ±1.5% over temperature, enabling accurate 1.0 V, 1.2 V, or 1.5 V rails for modern digital ICs. Operation below 0.8 V is not supported, as the internal error amplifier reference is fixed.

Does LM20136MH/NOPB support startup into a pre-biased output?

Yes, the LM20136MH/NOPB supports pre-bias startup: when VOUT is non-zero at enable, the device will not sink current from the output until the SS/TRK voltage exceeds the FB voltage. This prevents back-driving of powered loads such as FPGA I/O banks or memory interfaces, avoiding potential damage or system lockup during hot-insertion scenarios.

How does the LM20136MH/NOPB handle frequency synchronization?

The LM20136MH/NOPB uses its SYNC pin to accept external clock signals from 500 kHz to 1.5 MHz. The high-side switch locks to the rising edge of SYNC; logic thresholds are 0.8 V (low) and 2.0 V (high). If SYNC is grounded, the device operates at ~410 kHz. This capability enables EMI reduction in multi-converter systems and avoids interference with sensitive RF or data acquisition circuits.

What thermal performance can be expected from LM20136MH/NOPB in a standard PCB layout?

In a 2" × 2" FR4 4-layer board with the exposed pad soldered to a solid ground plane, the LM20136MH/NOPB achieves θJA = 25°C/W. At 6 A output and 5 V input, typical power dissipation is ~1.2 W, resulting in ~30°C junction-to-ambient rise above ambient-well within the 125°C max operating junction temperature. Thermal shutdown activates only under sustained overload or inadequate copper area.

Can LM20136MH/NOPB be used without an external compensation network?

No-LM20136MH/NOPB requires external RC components on the COMP pin for loop stability. While the current-mode architecture simplifies compensation, omitting the network causes instability and oscillation. A typical design uses a series RC (e.g., 2.7 kΩ + 1 nF) from COMP to AGND, with optional feedforward capacitor. TI's WEBENCH® and SNVS564B design guide provide validated networks for common VOUT/fSW configurations.