Renesas UPD166021T1F-E1-AY

Overview

UPD166021T1F-E1-AY from Renesas Electronics is a single N-channel high-side power switch with integrated charge pump, load current sensing (K_ILIS = 8.3–11.0 k), short-circuit and overtemperature protection, and reverse battery tolerance up to −16 V. It delivers 7.5 A continuous load current with 14–18 mΩ on-resistance at 25°C and supports automotive 14 V DC grounded loads including LED lamps up to 65 W.

For engineers reviewing the UPD166021T1F-E1-AY datasheet, UPD166021T1F-E1-AY pinout, UPD166021T1F-E1-AY application, or UPD166021T1F-E1-AY equivalent, this device serves as a fuse- and relay-replacement smart power switch for automotive body electronics requiring diagnostic feedback, robust fault handling, and AEC-Q100 qualification.

Technical Context

The UPD166021T1F-E1-AY integrates a self-contained charge pump to drive the N-channel MOSFET gate above VCC, enabling true high-side switching without external bootstrap components. Its control logic implements latched shutdown on overcurrent (IL(SC) = 5–200 A depending on VCC and V_ON) or overtemperature (T_th = 150–175°C), with fault signaling via IS pin current clamping at 3.5–12.0 mA.

Diagnostic functionality includes proportional current sense (I_IS = I_L/K_ILIS) with offset <1 μA and saturation limit of 3.5–12.0 mA, plus dynamic clamp activation during inductive load turn-off to limit V_OUT to 30–40 V. Reverse battery protection engages via internal N-MOSFET conduction when V_CC < 0 V, limiting dissipation with R_on(rev) = 9.5–22 mΩ.

Key Specifications

Pinout & Package

Package: 5-pin TO-252 (MP-3ZK), JEDEC standard, MSL Level 3, Pb-free Sn plating. Tab (Pin 3) is internally connected to VCC and serves as primary thermal path.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side switch applications.

Compared with UPD166021T1F-E1-AY, the BTS4141N offers superior efficiency but demands additional gate-drive infrastructure, while the NCV8460A maintains mechanical and functional compatibility at reduced current rating - making it suitable for de-rated designs where layout reuse is critical.

Availability

UPD166021T1F-E1-AY is available at Aetrix Electronics and suitable for automotive lighting control, body electronics power distribution, and solid-state fuse replacement requiring stable component supply, AEC-Q100 compliance, and long-term production continuity.

Supply support for UPD166021T1F-E1-AY 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

Renesas Electronics is a global semiconductor leader specializing in microcontrollers, analog, power, and SoC solutions for automotive, industrial, and IoT markets.

The UPD166021T1F-E1-AY belongs to Renesas' automotive-grade smart power switch family, designed specifically for replacing mechanical relays and fuses in 12 V vehicle electrical systems with integrated diagnostics and protection.

FAQ

What is the maximum continuous load current supported by the UPD166021T1F-E1-AY?

The UPD166021T1F-E1-AY supports 7.5 A continuous load current at T_ch = 25°C with R_on = 14–18 mΩ. Derating applies per thermal data: at T_ch = 150°C, R_on increases to 18 mΩ, limiting practical continuous current to ~5.5 A on a standard 50 mm × 50 mm FR4 PCB with 6 cm² copper. The device also supports short-circuit currents up to 200 A depending on V_CC−V_IN and V_ON, with latched shutdown activation.

How does the UPD166021T1F-E1-AY implement reverse battery protection?

The UPD166021T1F-E1-AY uses its internal N-channel MOSFET's body diode and gate-control logic to self-turn-on during reverse battery events (down to −16 V), routing reverse current through the channel instead of the lossy body diode. This reduces power dissipation versus passive diode solutions, with R_on(rev) = 9.5–22 mΩ depending on temperature. External R_IN must be sized per datasheet formula to limit reverse current to safe levels.

Can the UPD166021T1F-E1-AY be used without connecting the IS pin?

Yes - if current sensing and diagnostics are unused, the IS pin must be connected to GND via a resistor (typically 1 kΩ, per datasheet note). Leaving IS floating risks undefined behavior or false fault signals. When connected, IS outputs proportional current I_IS = I_L/K_ILIS (8.3–11.0 k) with <1 μA offset, or clamps to 3.5–12.0 mA during faults for unambiguous status indication.

What is the purpose of the dynamic clamp circuit in the UPD166021T1F-E1-AY?

The dynamic clamp activates only during inductive load turn-off, when V_OUT falls below ground. It connects an internal clamp diode to the output MOSFET gate, limiting V_OUT to 30–40 V and absorbing inductive energy (EAS1 = 50 mJ). This prevents voltage overshoot damage to the switch or downstream components without dissipating energy during normal operation - unlike static clamps that continuously load the supply.

Is the UPD166021T1F-E1-AY pin-compatible with other Renesas high-side switches?

No - the UPD166021T1F-E1-AY has a unique 5-pin TO-252 (MP-3ZK) pinout with Pins 1 & 5 both designated OUT and requiring external shorting. Other Renesas devices like the UPD16601x series use different pin configurations and protection schemes. Mechanical compatibility does not imply electrical or functional interchangeability; always verify block diagram, truth table, and timing against the target design.