Texas Instruments TPS65835RKPT

Overview

TPS65835RKPT from Texas Instruments is an integrated power management unit (PMU) with embedded MSP430 microcontroller, designed specifically for active shutter 3D glasses. It combines a linear Li-ion battery charger (pre-charge/fast-charge/termination), adjustable 8–16 V boost converter, dual full H-bridge analog switches for left/right LC shutter control, 2.2 V or 3.0 V LDO, and system power path management - all in a single 40-pin VQFN package.

For engineers reviewing the TPS65835RKPT datasheet, TPS65835RKPT pinout, TPS65835RKPT application, or TPS65835RKPT equivalent, this device requires attention to its dual-domain architecture (PMIC + MCU), H-bridge timing synchronization, battery thermal regulation thresholds (75–95 °C), I_CHG set via external R_ISET, and SW_SEL–controlled power-up sequencing for push-button vs. slider switch interfaces.

Technical Context

The TPS65835RKPT implements a tightly coupled PMIC-MCU architecture: the MSP430 core (16-bit RISC, 16 kB Flash, 10-bit ADC, UART/I²C/SPI) directly controls H-bridge switching states, interprets IR/RF sync signals, and manages charger state transitions - eliminating need for external host controller. Its power path supports simultaneous system operation and battery charging with dynamic current sharing.

Key functional blocks include a linear charger with NTC thermistor monitoring (via TS pin), programmable LDO output voltage (2.2 V or 3.0 V via VLDO_SET), boost converter with internal MOSFET and diode (V_{BST_OUT} = 8–16 V), and four dedicated H-bridge terminals (LCLP/LCLN/LCRP/LCRN) with 20–40 Ω R_DS(ON). All logic-level GPIOs (BST_EN, CHG_EN, SLEEP, etc.) operate at 1.2 V high / 0.4 V low thresholds referenced to VSYS.

Key Specifications

Pinout & Package

TPS65835RKPT uses a 40-pin VQFN package (RKP) with 4.00 mm × 4.00 mm body size and exposed thermal pad connected internally to AGND. The thermal pad must be soldered to PCB ground plane for thermal performance and electrical reference integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PMU-with-integrated-MCU applications.

Compared with TPS65835RKPT, TPS65836RKPT offers higher processing headroom at the cost of increased power and toolchain complexity, while BQ24250RGET provides charger-only functionality requiring three additional ICs to replicate full TPS65835RKPT capability - making TPS65835RKPT optimal for cost- and space-constrained active shutter systems.

Availability

TPS65835RKPT is available at Aetrix Electronics and suitable for active shutter 3D glasses, portable LC shutter modules, and battery-powered wearable displays requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for TPS65835RKPT 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 company specializing in analog, embedded processing, and power management technologies, with decades of leadership in precision analog ICs and low-power microcontrollers.

The TPS65835RKPT belongs to TI's Active Shutter 3D Power Management portfolio, engineered to consolidate power delivery, battery management, and real-time shutter control into one die - targeting ultra-compact, battery-efficient 3D eyewear with minimal external components.

FAQ

What is the function of the SW_SEL pin on the TPS65835RKPT?

The SW_SEL pin on the TPS65835RKPT configures the device's power-up behavior: logic-low selects push-button switch mode (momentary activation), while logic-high selects slider switch mode (latching on/off). This setting determines how the MSP430 core interprets the SWITCH pin input and initiates the correct state machine sequence during startup. The TPS65835RKPT datasheet defines exact timing and debounce requirements for each mode in Section 5.3.1.

Can the TPS65835RKPT operate without a battery connected?

Yes, the TPS65835RKPT can operate without a battery. When VIN is present and BAT is open or disconnected, the power path automatically routes input power to SYS and VLDO rails while disabling the charger. The MSP430 core remains fully functional, and H-bridge drivers can be controlled normally. However, nCHG_STAT will remain asserted (low) and battery-related features (DPPM, NTC monitoring, charge termination) are inactive. The TPS65835RKPT supports instant system turn-on even with a totally discharged or absent battery pack.

How is the boost output voltage set on the TPS65835RKPT?

The TPS65835RKPT boost output voltage is set using an external resistive divider from BST_OUT to BST_FB to ground. The internal reference is 1.20 V (±2.5% hysteresis) on BST_FB, so V_{BST_OUT} = 1.2 × (1 + R1/R2). For example, to achieve 12 V output, use R1 = 90 kΩ and R2 = 10 kΩ. The TPS65835RKPT datasheet specifies minimum BST_OUT capacitance (≥3.3 µF) and recommends ceramic capacitors with X7R dielectric for stability.

What thermal protection mechanisms does the TPS65835RKPT implement?

The TPS65835RKPT implements three-tier thermal protection: (1) Charger thermal regulation between 75 °C (TJ(REG_LOWER)) and 95 °C (TJ(REG_UPPER)), where charge current is reduced linearly; (2) Boost converter thermal shutdown at 105 °C (TSHUT(BST)) with 20 °C hysteresis; and (3) Global junction shutdown at 105 °C (TJ(OFF)). All thresholds are measured at the die, and the TPS65835RKPT's RθJA of 38.9 °C/W requires proper PCB copper pour under the thermal pad for reliable operation.

Is the MSP430 core in the TPS65835RKPT field-programmable?

Yes, the MSP430 core in the TPS65835RKPT is field-programmable via Spy-Bi-Wire (SBW) interface using pins TCK, TMS, and SBWTCK/SBWTIO (Pins 39, 40, 20, 17). It supports in-system programming without external voltage; code protection is implemented via security fuse. Firmware updates require TI's MSP430 Flash Emulation Tool (FET) or compatible debugger. The TPS65835RKPT's 16 kB Flash memory allows storage of full shutter control logic, IR protocol stacks, and battery management routines.