Texas Instruments BQ76PL536APAPR

Overview

BQ76PL536APAPR from Texas Instruments is a stackable 3-to-6 series cell lithium-ion battery monitor and secondary protection IC with integrated 14-bit ADC (±1 mV typical accuracy), six cell-balancing control outputs, dual temperature sensing inputs, and programmable overvoltage/undervoltage/overtemperature protection. It operates across 7.2 V to 27 V supply and supports large-format battery stacks up to 192 cells in daisy-chained configurations for UPS and e-mobility systems.

For engineers reviewing the BQ76PL536APAPR datasheet, BQ76PL536APAPR pinout, BQ76PL536APAPR application, or BQ76PL536APAPR equivalent, key selection considerations include its HTQFP-64 package, SPI host interface with vertical daisy-chain capability, ±1 mV cell voltage measurement accuracy, 6-µs per-channel conversion time, and integrated 5-V REG50 LDO output for auxiliary circuitry.

Technical Context

The BQ76PL536APAPR integrates two independent ADC subsystems: one dedicated to six cell voltages (VC1–VC6) and brick voltage (VBAT), another to two differential temperature sensors (TS1±, TS2±) and GPAI±. All nine analog inputs share 14-bit resolution and ±1 mV typical accuracy at 25°C.

Its protection architecture uses non-volatile OTP registers to store user-programmable thresholds and delay times for overvoltage (2–5 V range, 50-mV steps), undervoltage (0.7–3.3 V, 100-mV steps), and overtemperature (1–2 V range, programmable hysteresis). Fault detection triggers dedicated open-drain ALERT_H, FAULT_H, and DRDY_H signals, while vertical interfaces (CONV_N/S, CS_N/S, SCLK_N/S, SDO_N/S, etc.) enable synchronized conversions and SPI data routing across stacked devices without isolation components.

Key Specifications

Pinout & Package

Package: HTQFP-64 (10.00 mm × 10.00 mm) with exposed thermal pad soldered to VSS for thermal performance (R_θJB = 8.1°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar battery monitor and protector applications.

Compared with BQ76PL536AQPAPRQ1, the BQ76PL536APAPR offers lower cost and identical core functionality for industrial use, while the MAX17853 provides greater analog input flexibility at the expense of added power-supply complexity and reduced voltage accuracy.

Availability

BQ76PL536APAPR is available at Aetrix Electronics and suitable for uninterruptible power systems (UPS), e-bike and e-scooter battery management, and large-format energy storage systems requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for BQ76PL536APAPR 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 and embedded processing technologies, with leadership in battery management, power management, and signal chain solutions.

The BQ76PL536APAPR belongs to TI's bq™ precision battery monitoring portfolio, designed specifically for high-reliability, multi-cell lithium-ion battery protection and state estimation in industrial and transportation applications.

FAQ

What is the maximum number of BQ76PL536APAPR devices that can be stacked in a daisy-chain configuration?

The BQ76PL536APAPR supports stacking up to 32 devices in a vertical daisy-chain, enabling monitoring of up to 192 cells (32 × 6). This is achieved using current-mode vertical interfaces (CONV_N/S, CS_N/S, etc.) that eliminate the need for isolation components between devices, maintaining signal integrity and timing synchronization across the entire stack. Each BQ76PL536APAPR device manages its own six-cell segment while forwarding SPI and control signals to adjacent units.

Does the BQ76PL536APAPR integrate an internal voltage reference, and how is it stabilized?

Yes, the BQ76PL536APAPR integrates an internal analog voltage reference (VREF) with a nominal output of ~2.048 V, derived from the internal bandgap. It requires a 10-µF, low-ESR ceramic capacitor connected between VREF and AGND for stability, as specified in the datasheet. This reference is used for all ADC conversions-including cell voltages, temperature, and GPAI-ensuring consistent measurement accuracy across operating conditions. The BQ76PL536APAPR does not rely on external references for core AFE functions.

Can the BQ76PL536APAPR perform simultaneous cell voltage measurements, and what is the timing behavior?

No, the BQ76PL536APAPR performs sequential cell voltage measurements-not true simultaneous sampling-but achieves synchronized acquisition across stacked devices via the CONV_N/S interface. Each conversion takes 6 µs per channel, so measuring all six cells requires ~42 µs total. The CONV_H pin initiates conversion, and DRDY_H asserts upon completion. When stacked, a master CONV pulse propagates through the chain, ensuring all devices sample within <100 µs skew-functionally equivalent to synchronized measurement for BMS state estimation.

What are the absolute maximum ratings for cell voltage inputs (VC1–VC6) on the BQ76PL536APAPR?

The absolute maximum rating for each cell voltage input (VC1–VC6) on the BQ76PL536APAPR is –0.3 V to +36 V with respect to VSS. However, the recommended operating range for accurate measurement is 0 V to +6 V differential (VCn – VCn–1), with guaranteed performance from 1 V to 4.5 V. Exceeding the 6-V differential limit risks damage to the internal ESD protection structures, and operation outside the 1–4.5 V range degrades accuracy-particularly near the extremes-due to ADC nonlinearity and offset drift.

How does the BQ76PL536APAPR handle thermal shutdown, and what are the recovery characteristics?

The BQ76PL536APAPR features integrated thermal shutdown (TSD) with a trip threshold of 125°C to 156°C (typical 142°C) and hysteresis of 8°C to 25°C. Upon triggering, TSD disables all analog functions except the ALERT_STATUS[TSD] flag and forces the device into a safe state-halting conversions, disabling CBx outputs, and asserting FAULT_H. Recovery occurs automatically once junction temperature falls below (trip threshold – hysteresis); no reset or power cycle is required. The BQ76PL536APAPR continues to report TSD status via register reads until cleared by host software.