STMicroelectronics L9822E

Overview

L9822E from STMicroelectronics is an octal low-side solenoid driver IC in Multipower-BCD technology, featuring eight 0.5 Ω (at 1 A, 25 °C) DMOS outputs, SPI serial interface, 8-bit diagnostic feedback, internal 36 V clamping per output, and chip-enable–controlled latch transfer-designed for automotive lamp, relay, and solenoid control with overload and open-circuit fault detection.

For engineers reviewing the L9822E datasheet, L9822E pinout, L9822E application, or L9822E equivalent, key selection criteria include R_DS(on) stability across temperature, SPI timing compliance (2 MHz max), diagnostic bit alignment with output channels, and thermal resistance (1.5 °C/W junction-to-case in PowerSO20) for high-reliability automotive power distribution.

Technical Context

The L9822E integrates three core functional blocks: an 8-bit SPI shift register for serial data ingestion and diagnostic readback, a parallel latch that holds output states and resets on fault detection, and eight independent DMOS output stages with analog current limiting (≥1.05 A), voltage-sense comparators (trip threshold 1.6–2 V), and integrated 36 V zener clamps. All outputs share a common asynchronous RESET but operate independently under CE-gated latch control.

Diagnostic operation requires two-phase SPI transfer: first, CE falling edge latches real-time output voltage status (high = >1.8 V ON-state fault or open-circuit pull-down; low = normal OFF or loaded ON); second, CE rising edge transfers new control bits to outputs after a 75–250 µs fault-reset delay window during which current limiting remains active but comparator-based latch reset is inhibited.

Key Specifications

Pinout & Package

Available in Multiwatt15 (through-hole) and PowerSO20 (surface-mount) packages. PowerSO20 offers lower thermal resistance (1.5 °C/W vs. 2 °C/W) and higher power density for space-constrained automotive ECUs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal low-side driver applications.

Compared with TLE6232GP and VN808CM-E, the L9822E uniquely balances full 8-channel integration, built-in 36 V clamping, and bidirectional SPI diagnostics in a single PowerSO20 package-making it optimal for space-constrained automotive body electronics where fault visibility and component count reduction are critical.

Availability

L9822E is available at Aetrix Electronics and suitable for automotive body control modules, industrial solenoid valve banks, and commercial vehicle lighting systems requiring stable component supply across extended product lifecycles.

Supply support for L9822E 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets since 1987.

The L9822E belongs to ST's Automotive Power Switch portfolio, engineered specifically for robust, fault-aware control of inductive and resistive loads in harsh 12 V/24 V vehicle environments.

FAQ

What is the maximum safe operating frequency of the SPI interface for L9822E?

The L9822E supports SPI clock frequencies up to 2 MHz under all specified conditions (V_CC = 5 V ±5%, T_j = –40 °C to 125 °C). Timing parameters including t_lead (250 ns), t_lag (250 ns), and t_su/t_H (75 ns each) are guaranteed across this range. Exceeding 2 MHz risks setup/hold violations and unreliable diagnostic readback.

How does the L9822E detect open-circuit conditions on an output programmed OFF?

When an output is programmed OFF, its internal voltage comparator applies a weak pulldown current. If the output pin is truly open-circuited, the pin floats to near GND potential, causing the comparator to report a logic low on the corresponding SO bit. A mismatch between the sent OFF command (SI = high) and received low SO bit confirms open-circuit status.

Can multiple L9822E devices be cascaded using a single SPI bus? How is synchronization managed?

Yes-L9822E supports daisy-chain configuration via shared SCLK, SI, and CE lines. The SO of one device connects to the SI of the next. CE must be asserted simultaneously across all devices; on CE rising edge, each device latches its own shift register contents to outputs independently, preserving channel isolation while enabling unified command broadcast.

What thermal derating applies when operating the L9822E in PowerSO20 at 125°C ambient?

In PowerSO20, R_{th j-amb} is 60 °C/W. At 125°C ambient, maximum allowable power dissipation is (150°C – 125°C) / 60 °C/W = 0.417 W. With eight outputs at 0.55 Ω and 500 mA each, total conduction loss is 8 × (0.55 × 0.5²) = 1.1 W-exceeding safe limit. Derating requires reducing simultaneous active channels or lowering load current to maintain T_j ≤ 150°C.