onsemi CS8281YDP5

Overview

CS8281YDP5 from onsemi is a dual-output micropower low-dropout linear voltage regulator with independent 5.0 V/250 mA primary (VOUT1) and 5.0 V/100 mA secondary (VOUT2) outputs, 3.0% output tolerance, ENABLE-controlled primary output, and integrated reverse-battery (−15 V), load-dump (74 V), short-circuit, overtemperature (150 °C trip), and overvoltage (34 V shutdown) protection - used in automotive body control modules requiring robust, always-on standby power.

For engineers reviewing the CS8281YDP5 datasheet, pinout, applications, or equivalent options, key selection criteria include dual-rail 5 V regulation under wide input (−15 V to 74 V), ultra-low quiescent current (100 µA with VOUT2 active only), D2PAK−5 thermal performance (R_JC = 2.4 °C/W), and logic-level ENABLE compatibility with battery-tied resistor networks.

Technical Context

The CS8281YDP5 integrates two independent LDO regulators sharing a common ground and thermal shutdown circuitry, where VOUT2 powers internal bias and remains always active, while VOUT1 is gated by the CMOS-compatible ENABLE pin. Its architecture supports direct battery connection with no external reverse-polarity protection required.

It operates across −40 °C to +125 °C ambient, sustains 600 mV max dropout at full load, delivers 70 dB ripple rejection at 120 Hz, and features separate current limiting (400 mA for VOUT1, 200 mA for VOUT2) and short-circuit foldback (25 mA per output) - all within a single D2PAK−5 package with exposed tab for thermal conduction.

Key Specifications

Pinout & Package

D2PAK−5 package (Case 936AC) with exposed metal tab electrically connected to Pin 3 (GND) for enhanced thermal dissipation and mechanical mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output automotive LDO regulator applications.

Compared with TLV70733PDPWR and TPS7B8133QDGNRQ1, the CS8281YDP5 uniquely integrates dual 5 V outputs with battery-direct operation, built-in transient protection, and ENABLE-controlled power gating - eliminating four to six external components in automotive body electronics.

Availability

CS8281YDP5 is available at Aetrix Electronics and suitable for automotive body control modules, door module controllers, seat control units, and roof modules requiring stable component supply under harsh electrical environments.

Supply support for CS8281YDP5 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient electronics, with leadership in automotive, industrial, and cloud power solutions.

The CS8281YDP5 belongs to onsemi's SMART REGULATOR™ family - designed specifically for automotive power management applications demanding high transient immunity, ultra-low quiescent current, and integrated protection without external components.

FAQ

What is the maximum input voltage the CS8281YDP5 can withstand without damage?

The CS8281YDP5 supports an absolute maximum input voltage of +74 V and can tolerate −15 V reverse battery conditions without external protection components. This rating covers ISO 7637-2 Pulse 5a (load dump) and reverse-polarity events common in 12 V automotive systems. Operation above 26 V reduces power dissipation margin but remains within safe operating area as long as thermal limits are observed. The CS8281YDP5 internal overvoltage shutdown activates at 34 V to protect downstream circuitry.

How does the ENABLE pin function in the CS8281YDP5, and what are its voltage thresholds?

The ENABLE pin on the CS8281YDP5 is a CMOS-compatible digital input that controls only the primary output (VOUT1). When ENABLE is pulled above 2.0 V (typical), VOUT1 turns on; when pulled below 0.8 V (typical), VOUT1 shuts off while VOUT2 remains active. The pin draws ≤2.0 µA bias current and tolerates up to 6.0 V. Per Figure 3 in the datasheet, it can be directly tied to the battery rail through a 10 kΩ resistor, enabling simple ignition-switched control without additional level-shifting circuitry. The CS8281YDP5 maintains this behavior across −40 °C to +125 °C.

Why does VOUT1 collapse when VOUT2 experiences an overcurrent condition in the CS8281YDP5?

VOUT2 supplies all internal bias current for the CS8281YDP5, including bandgap reference, error amplifiers, and protection circuitry. If VOUT2 collapses due to overload or short circuit, internal bias fails and VOUT1 regulation ceases - even if ENABLE is asserted. This design ensures fail-safe behavior: critical systems powered by VOUT2 remain functional, while non-critical loads on VOUT1 are disabled during fault conditions. The CS8281YDP5 datasheet explicitly states this dependency in the Application Notes section and Figure 2 waveform diagram.

What output capacitor values and ESR requirements are specified for stable operation of the CS8281YDP5?

The CS8281YDP5 requires minimum 22 µF output capacitors on both VOUT1 and VOUT2, with effective series resistance (ESR) less than 8 Ω, as confirmed in Figure 5 and Application Notes. These capacitors must operate reliably down to −40 °C; standard tantalum or low-ESR ceramic types meeting that temperature rating are acceptable. Larger capacitance values improve transient response and maintain output during negative input transients. The CS8281YDP5 becomes unstable without these capacitors, exhibiting oscillation per the datasheet stability requirements.

Does the CS8281YDP5 meet AEC-Q100 qualification standards for automotive use?

The CS8281YDP5 is not explicitly listed as AEC-Q100 qualified in its official datasheet (Rev. 9, 2004), though it was designed for automotive environments with features aligned to AEC-Q100 stress categories: operating temperature range (−40 °C to +125 °C), robust transient protection (−15 V reverse, 74 V load dump), and failure-mode coverage (overtemperature, overvoltage, short-circuit). For new designs requiring formal AEC-Q100 certification, engineers should verify qualification status with onsemi or select a designated AEC-Q100 part such as the TPS7B8133QDGNRQ1. The CS8281YDP5 remains widely used in legacy automotive modules where qualification was not mandated at time of design-in.