L4936E

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Overview

The L4936E is a monolithic dual linear voltage regulator designed for microcomputer systems, particularly in automotive environments. It features two low-dropout outputs: Output 1 provides a fixed 5V at up to 100mA, while Output 2 delivers 5V at up to 400mA or offers adjustable regulation via an external divider. The device operates within a DC supply range of 5V to 28V and withstands transients up to 40V. Key auxiliary functions include a programmable power-on reset circuit with thresholds between 3.8V and 4.7V, a sense comparator for input monitoring, and thermal shutdown protection.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Feature Summary

• Dual output architecture providing independent 100mA and 400mA regulated rails with extremely low dropout characteristics
• Integrated power-on reset generator with user-programmable threshold voltage and delay timing capabilities
• Input sense comparator with dedicated output for supervising supply levels and detecting undervoltage conditions
• Robust input protection on Enable and Sense pins against negative transients down to -5V

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Applications

• Microprocessor power supply units in automotive electronic control modules
• Systems requiring simultaneous stable logic and high-current peripheral voltages
• Circuits needing integrated input voltage supervision and reset signal generation

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Procurement Notes

Verify component authenticity through authorized STMicroelectronics distributors due to obsolete status. Confirm package integrity as the Multiwatt-11 housing may show handling wear. Ensure design compatibility with legacy automotive standards, as RoHS compliance is not guaranteed for this specific revision. Validate thermal management requirements against the specified junction temperature limits during final assembly.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Selection Notes

Select this component when designing systems requiring a single-chip solution for dual voltage regulation combined with reset and sensing functions. It is suitable for applications where space constraints prevent using separate regulators and supervisors. Consider the Multiwatt-11 package for through-hole mounting requirements. Evaluate the need for external components to program the reset threshold and delay times according to specific system startup sequences.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Part Context

This device belongs to the L4936 family of advanced voltage regulators from STMicroelectronics. It shares architectural similarities with other automotive-grade PMICs but distinguishes itself through the integration of a sense comparator alongside dual linear regulators. The Multiwatt-11 variant offers a compact footprint compared to the Multiwatt-15 version, making it ideal for dense PCB layouts in vehicle instrumentation and control units.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Replacement Considerations

L4936EH (Multiwatt-15 package variant)

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators FAQ

How is the reset threshold voltage adjusted?

The reset threshold can be programmed continuously between 3.8V and 4.7V by connecting an external resistor from the PR pin to ground.

What happens if Output 2 reaches thermal shutdown?

Output 2 shuts down approximately 10°C before Output 1, allowing the chip to cool down while keeping Output 1 operational under normal conditions.

Can Output 2 voltage be adjusted?

Yes, Output 2 voltage is adjustable via an external voltage divider connected to the ADJ pin, provided it is not wired directly to VOUT2.