Microchip Technology MCP1664T-E/OTVAO

Overview

MCP1664T-E/OTVAO from Microchip Technology is a fixed-frequency, non-synchronous step-up DC-DC converter optimized for constant-current LED driving from 2–3-cell alkaline/NiMH or single-cell Li-Ion batteries. It integrates a 36V, 400 mΩ low-side NMOS switch, delivers up to 300 mA LED current at 5.0V input (4 white LEDs), features 500 kHz PWM switching, 300 mV feedback reference, and AEC-Q100 qualification for automotive backlighting and flash applications.

For engineers reviewing the MCP1664T-E/OTVAO datasheet, MCP1664T-E/OTVAO pinout, MCP1664T-E/OTVAO application, or MCP1664T-E/OTVAO equivalent, key selection considerations include its 2.4–5.5V input range, 32V max output, 1.8A peak inductor current limit, open-load protection (OLP), and thermal shutdown-critical for portable LED lighting where battery headroom, reliability, and fault resilience are design priorities.

Technical Context

The MCP1664T-E/OTVAO implements peak current-mode control with internal slope compensation, using VSENSE derived from the integrated 400 mΩ switch to regulate LED current via a 300 mV VFB reference. Its 500 kHz oscillator enables compact magnetics and low EMI, while cycle-by-cycle current limiting and UVLO (2.3V start / 1.85V stop) ensure stable startup and brownout recovery across battery discharge profiles.

Open-load protection activates when VFB falls below 50 mV-indicating LED string disconnection or VFB-to-GND short-halting switching to prevent SW node overvoltage and output overvoltage. Thermal shutdown at +150°C (20°C hysteresis) and internal compensation eliminate external loop components, supporting robust, space-constrained implementations in handheld and automotive lighting.

Key Specifications

Pinout & Package

Package: 5-Lead SOT-23 (no exposed pad). Pin assignments are validated per Microchip DS20005408B, Table 3-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED driver applications.

Compared with TPS61061DRVR and MAX16832ATA+T, the MCP1664T-E/OTVAO uniquely combines AEC-Q100 qualification, integrated 36V switch, OLP, and ultra-low 40 nA shutdown current-making it the optimal choice for space-constrained, safety-critical, battery-powered LED systems where reliability and integration outweigh raw output voltage or frequency flexibility.

Availability

MCP1664T-E/OTVAO is available at Aetrix Electronics and suitable for automotive instrument clusters, portable medical flash units, Li-Ion camera modules, and handheld gaming device backlighting requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for MCP1664T-E/OTVAO 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

Microchip Technology is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and power management ICs, with a focus on embedded control and energy-efficient solutions.

The MCP1664 product line was designed specifically for high-efficiency, constant-current LED driving in portable and automotive applications where battery voltage varies widely and fault protection is critical.

FAQ

What is the maximum number of white LEDs the MCP1664T-E/OTVAO can drive?

The MCP1664T-E/OTVAO supports up to 10 white LEDs in series, constrained by its 32V maximum output voltage and typical forward voltage of ~3.2V per LED. With 8 LEDs (≈25.6V total VF), the device delivers up to 150 mA at 4.2V input, as confirmed in Figure 2-6 of DS20005408B. Exceeding 32V risks violating absolute maximum ratings and triggering OLP.

Does the MCP1664T-E/OTVAO require external compensation components?

No, the MCP1664T-E/OTVAO includes fully integrated compensation circuitry. Its error amplifier and associated network are built-in, eliminating the need for external capacitors or resistors in the feedback loop. This simplifies design, reduces board area, and improves production yield-verified in Section 4.2.6 and Figure 4-1 of DS20005408B.

How does Open Load Protection (OLP) function in the MCP1664T-E/OTVAO?

OLP in the MCP1664T-E/OTVAO monitors the VFB pin voltage. If VFB drops below 50 mV-indicating an open LED string or VFB-to-GND short-the device halts switching to prevent SW node overvoltage and output overvoltage. This protection is disabled during startup and thermal shutdown, as documented in Sections 4.2.7 and 5.2.4 of DS20005408B.

What is the recommended input capacitor for the MCP1664T-E/OTVAO at 3.3V input?

For 3.3V input, Microchip recommends a 4.7–10 µF X7R ceramic capacitor placed close to the VIN and GND pins. At lower inputs (<3.0V) or high-current loads, 20–30 µF is advised to maintain stability-per Section 5.3 and Figure 2-1 of DS20005408B. Low-ESR construction is mandatory for reliable operation up to +125°C ambient.

Is the MCP1664T-E/OTVAO pin-compatible with other packages in the MCP1664 family?

No-MCP1664T-E/OTVAO uses the 5-lead SOT-23 package, which has different pinout and thermal characteristics than the 8-lead 2 mm × 3 mm TDFN variant (e.g., MCP1664-E/CHY). The SOT-23 lacks SGND, PGND, and NC pins present in the TDFN; mixing packages requires PCB redesign. Package-specific details are in Table 3-1 of DS20005408B.