Texas Instruments LP87702KRHBTQ1

Overview

LP87702KRHBTQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive power management IC integrating two 3.5-A buck converters (0.7–3.36 V, 2–4 MHz), one 5-V/600-mA boost converter, dual voltage monitoring inputs, programmable power-good signals, window watchdog with reset output, and I²C interface up to 3.4 MHz. It serves as a primary power supply for radar and camera sensor modules requiring functional safety diagnostics.

For engineers reviewing the LP87702KRHBTQ1 datasheet, LP87702KRHBTQ1 pinout, LP87702KRHBTQ1 application, or LP87702KRHBTQ1 equivalent, key selection criteria include diagnostic coverage (VMON1/VMON2, PG0/PG1, WDI/WD_RESET), synchronized multi-rail sequencing, spread-spectrum EMI reduction, and thermal warning/shutdown thresholds at 125 °C and 140 °C.

Technical Context

The LP87702KRHBTQ1 implements dual independent buck regulators with auto PWM/PFM mode switching and remote voltage sensing to compensate IR drop at point-of-load. Each buck supports programmable current limiting (1.5–4.5 A), slew-rate control (0.47–15 mV/µs), and ±2% DC accuracy in PWM mode.

Its integrated 5-V boost converter operates at 2 or 4 MHz with bypass mode capability, while the functional safety architecture includes dedicated reference voltage, two external voltage monitors, window watchdog with reset assertion, and overtemperature/overvoltage/short-circuit protection across all rails.

Key Specifications

Pinout & Package

VQFN-32 (RHB) package, 5.00 mm × 5.00 mm body size with exposed thermal pad for enhanced heat dissipation in automotive PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-rail automotive PMIC applications.

Compared with TPS65381A-Q1 and LM63625Q1RQARQ1, the LP87702KRHBTQ1 uniquely delivers dual high-current bucks plus boost in one package with full functional safety monitoring-enabling consolidation of three discrete regulators and a watchdog IC in radar camera designs.

Availability

LP87702KRHBTQ1 is available at Aetrix Electronics and suitable for automotive radar, camera, and sensor fusion applications requiring stable component supply, AEC-Q100 qualification, and functional safety documentation support.

Supply support for LP87702KRHBTQ1 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 for automotive, industrial, and communications markets.

The LP87702KRHBTQ1 belongs to TI's automotive-grade power management IC portfolio, designed specifically to address the stringent efficiency, diagnostics, and reliability demands of ADAS sensor modules and domain controllers.

FAQ

What is the maximum supported I²C clock frequency for the LP87702KRHBTQ1?

The LP87702KRHBTQ1 supports I²C up to 3.4 MHz in High-Speed mode. This enables rapid register access for dynamic voltage scaling and real-time fault logging. The interface maintains compatibility with Standard (100 kHz), Fast (400 kHz), and Fast+ (1 MHz) modes. All timing parameters-including t_LOW, t_HIGH, and t_SU;STA-are fully specified in the datasheet for robust implementation across speed grades. The LP87702KRHBTQ1 uses open-drain SDA/SCL with internal pull-down resistors and requires external pull-ups to V_IO.

Does the LP87702KRHBTQ1 support external clock synchronization, and how is it implemented?

Yes, the LP87702KRHBTQ1 supports external clock synchronization via the CLKIN pin (Pin 22). When enabled, this input replaces the internal oscillator to align switching frequencies across multiple LP87702KRHBTQ1 devices or with other system clocks-reducing beat frequencies and EMI peaks. The device detects valid external clocks within 20 µs and switches to them after a 600-µs delay. The LP87702KRHBTQ1 accepts 1–24 MHz inputs with ±10% accuracy and provides PLL output jitter of ≤300 ps p-p. CLKIN also serves as GPO2 or watchdog disable (WD_DIS).

How does the LP87702KRHBTQ1 handle thermal protection, and what are the warning and shutdown thresholds?

The LP87702KRHBTQ1 provides two-tier thermal protection: die temperature warning at 115–135 °C (configurable via TDIE_WARN_LEVEL) and thermal shutdown at 140–160 °C. Warning triggers the nINT pin to alert the host MCU, allowing graceful degradation (e.g., reducing processor load). Shutdown forces all regulators into high-impedance state to prevent damage. Hysteresis is fixed at 20 °C for both functions. These thresholds are measured at the die and validated across −40 °C to +125 °C ambient. The LP87702KRHBTQ1's R_θJA of 31.7 °C/W and exposed thermal pad ensure effective heat transfer in standard 4-layer automotive PCBs.

Can the LP87702KRHBTQ1's boost converter operate in bypass mode, and what is the voltage drop specification?

Yes, the LP87702KRHBTQ1's boost converter supports bypass mode, where SW_BST connects VIN_BST directly to VOUT_BST. In this mode, the device delivers up to 5.5 V input to the output with minimal loss. At 250 mA load, the typical voltage drop is 83 mV-enabling efficient pass-through operation for systems requiring 5-V rail conditioning without conversion loss. Bypass mode is selected via register control and retains short-circuit protection (270–420 mA limit). The LP87702KRHBTQ1 maintains the same 5-V nominal output accuracy (±3%) in boost mode and uses identical output capacitance (10–40 µF) for both configurations.

What diagnostic functions are integrated into the LP87702KRHBTQ1, and how are they used in functional safety systems?

The LP87702KRHBTQ1 integrates six diagnostic functions essential for ISO 26262-compliant systems: (1) two analog voltage monitors (VMON1/VMON2) for external supply validation, (2) two programmable power-good outputs (PG0/PG1), (3) window watchdog with dedicated WDI input and WD_RESET output, (4) dedicated reference voltage for calibration, (5) overtemperature warning and shutdown, and (6) OVP/UVLO on all power inputs. These features enable end-to-end fault detection-from input supply integrity to regulator output health-and support ASIL-B decomposition. The LP87702KRHBTQ1 provides functional safety documentation including FMEDA reports and safety manuals to aid system-level certification.