Texas Instruments TPS6521905RSMR

Overview

TPS6521905RSMR from Texas Instruments is a user-programmable Power Management IC (PMIC) integrating three synchronous step-down DC/DC converters (1×3.5A, 2×2A) and four LDOs (2×400mA, 2×300mA), operating from 2.5V–5.5V input. It supports dynamic voltage scaling, I²C-based power sequencing, and EEPROM configuration for industrial SoC power rails in AM62x/AM64x/AM243x-based systems.

For engineers reviewing the TPS6521905RSMR datasheet, TPS6521905RSMR pinout, TPS6521905RSMR application, or TPS6521905RSMR equivalent, key selection criteria include multi-rail sequencing capability, programmable buck/LDO output voltages (0.6V–3.4V and 1.2V–3.3V), low-quiescent-current PFM/PWM operation, and QFN-32 (4mm × 4mm) thermal performance across –40°C to +105°C.

Technical Context

The TPS6521905RSMR implements a triple-buck architecture with independent feedback loops (FB_B1/FB_B2/FB_B3), each supporting dynamic voltage scaling via I²C register writes. Its buck converters operate up to 2.3 MHz with quasi-fixed-frequency PWM/low-I_Q PFM modes and require only 470 nH inductors and ≥10 µF output capacitance per rail.

Four LDOs are partitioned into two groups: LDO1/LDO2 accept 1.5V–5.5V input and deliver 0.6V–3.4V at 400 mA with bypass-mode and SD-card voltage-select functionality; LDO3/LDO4 accept 2.2V–5.5V input and deliver 1.2V–3.3V at 300 mA with configurable load-switch behavior. All regulators support EEPROM-programmed default voltages and sequencing states.

Key Specifications

Pinout & Package

TPS6521905RSMR uses a 32-pin QFN package (4.00 mm × 4.00 mm, RSM variant) with exposed thermal pad (PGND) for enhanced thermal dissipation. Pin assignment follows TI's standardized RSM footprint, compatible with automated assembly and thermal vias under the pad.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PMIC applications.

Compared with TPS6521905RSMR, TPS6521815RSLR offers reduced feature set and fixed configuration for simplified deployment, while TPS659424RGER adds safety certification and scalability at the expense of size and industrial temperature range compliance.

Availability

TPS6521905RSMR is available at Aetrix Electronics and suitable for industrial HMI, PLC, video surveillance, and smart meter applications requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.

Supply support for TPS6521905RSMR 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 industrial-grade product validation.

The TPS6521905 belongs to TI's scalable, programmable PMIC family designed specifically for low-power industrial MPUs (AM62x/AM64x/AM243x), emphasizing EEPROM configurability, multi-rail sequencing, and extended temperature operation.

FAQ

What is the package type and thermal pad configuration of the TPS6521905RSMR?

The TPS6521905RSMR uses a 32-pin QFN package with 4.00 mm × 4.00 mm body size (RSM variant) and an exposed thermal pad (PGND). The pad must be connected to a continuous PCB ground plane using multiple thermal vias to achieve optimal thermal performance (R_ΘJB = 10.5 °C/W) and meet the –40°C to +105°C ambient specification. This configuration is distinct from the larger 5×5 mm RHB variant.

How does the TPS6521905RSMR support SD-card interface voltage switching?

The TPS6521905RSMR supports SD-card I/O voltage switching via the VSEL_SD function on pin 12 (VSEL_SD/VSEL_DDR). When configured as VSEL_SD, asserting this pin triggers a hardware-controlled transition between 1.8 V and the register-configured output voltage on LDO1 or LDO2 - meeting JEDEC UHS-I timing requirements without software intervention. This feature is confirmed in the device's pin function table and application diagrams.

Can the TPS6521905RSMR operate in multi-PMIC configurations, and how is synchronization achieved?

Yes, the TPS6521905RSMR supports multi-PMIC configurations for systems requiring more than 14 rails. Synchronization is achieved using the GPIO pin (pin 16) in synchronizing I/O mode, along with time-slot arbitration via the MODE/STBY and MODE/RESET pins. The datasheet confirms coordinated sequencing across two TPS6521905 devices, enabling deterministic power-up/down across complex industrial SoC platforms.

What are the absolute maximum ratings for input voltage on PVIN_B1 and VSYS pins?

The absolute maximum rating for VSYS is –0.3 V to 6 V. For PVIN_B1, PVIN_B2, and PVIN_B3, the absolute maximum is also –0.3 V to 6 V - but critically, these pins must not exceed VSYS by more than 200 mV. This constraint ensures safe operation of internal FETs and is explicitly defined in Section 5.1.3 of the TPS6521905 datasheet.

Does the TPS6521905RSMR support dynamic voltage scaling on all three buck converters?

Yes, the TPS6521905RSMR supports dynamic voltage scaling (DVS) on all three buck converters (BUCK1, BUCK2, BUCK3) via I²C register writes. Each buck's output voltage can be adjusted in real time in 25-mV steps (0.6 V–1.4 V) or 100-mV steps (1.4 V–3.4 V), enabling adaptive power management for CPU frequency scaling in AM62x/AM64x-based industrial applications.