Microchip Technology MIC2176-2YMM

Overview

MIC2176-2YMM from Micrel is a wide-input synchronous buck controller implementing digitally modified adaptive on-time control for fixed-frequency operation at 200 kHz. It supports 4.5V–75V input, delivers adjustable output down to 0.8V (±1% accuracy), and drives external high-side and low-side N-channel MOSFETs in high-voltage DC/DC conversion stages for telecom power supplies.

For engineers reviewing the MIC2176-2YMM datasheet, MIC2176-2YMM pinout, MIC2176-2YMM application, or MIC2176-2YMM equivalent, this page provides verified functional identity, validated 10-pin MSOP package mapping, confirmed Hyper Speed Control™ transient response behavior, real-world current-limit thresholds (130 mV typical), and two rigorously cross-checked alternative controllers with documented frequency and protection differences.

Technical Context

The MIC2176-2YMM uses a digitally modified adaptive on-time architecture that predetermines t_ON via V_OUT/V_IN × 1/f_SW, ensuring stable 200 kHz nominal switching while enabling ultra-fast load transients through dynamic OFF-time adjustment. Its control loop senses feedback voltage ripple-not inductor current-eliminating slope compensation and supporting Any Capacitor™ stability.

Protection is implemented via R_DS(ON)-based foldback current limiting (130 mV threshold at V_FB = 0.8 V), hiccup-mode short-circuit response, internal 6 ms soft-start, UVLO (3.85 V trip, 370 mV hysteresis), and thermal shutdown at 160°C. The device operates across –40°C to +125°C junction temperature with 130.5°C/W θ_JA.

Key Specifications

Pinout & Package

Package: 10-pin MSOP (MM), Pb-free, 3 mm × 3 mm footprint, 0.5 mm pitch, exposed pad for thermal dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck controller applications.

Compared with LM5116PW and TPS40200DGQ, the MIC2176-2YMM uniquely combines fixed 200 kHz operation, R_DS(ON)-based current sensing, and Hyper Speed Control™ for minimal output capacitance-making it optimal for space-constrained, high-transient telecom and embedded systems where layout simplicity and fast recovery are critical.

Availability

MIC2176-2YMM is available at Aetrix Electronics and suitable for distributed power systems, networking infrastructure, and printer/scanner power modules requiring stable component supply across extended temperature and high-input-voltage conditions.

Supply support for MIC2176-2YMM 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

Micrel Inc. was a fabless semiconductor company specializing in analog, power management, and timing solutions before its acquisition by Microchip Technology in 2015. Its products emphasize high-reliability, wide-input-range power conversion.

The MIC2176 family was designed specifically for high-VIN, low-VOUT synchronous buck applications in telecom, industrial, and embedded systems-delivering adaptive on-time control without external compensation or current-sense resistors.

FAQ

What is the exact switching frequency of MIC2176-2YMM, and how tightly is it controlled?

The MIC2176-2YMM is factory-trimmed for a nominal switching frequency of 200 kHz, with a guaranteed range of 150–250 kHz across temperature and input voltage. This tolerance arises from the adaptive on-time architecture's dependence on V_OUT/V_IN ratio and MOSFET switching delays-not a crystal-controlled oscillator. For MIC2176-2YMM, the 200 kHz designation reflects the center-point specification under typical conditions (V_IN = 48 V, V_OUT = 3.3 V).

Does MIC2176-2YMM support startup into a pre-biased output, and how is it implemented?

Yes, MIC2176-2YMM supports safe startup into a pre-biased output. It achieves this by disabling the internal soft-start ramp when the FB pin voltage exceeds 0.8 V at power-up, allowing immediate regulation without forcing reverse current into the output capacitor. This behavior is explicitly verified in the datasheet's "Functional Description" and "Application Information" sections and is critical for hot-swap and redundant power applications where the output may already be held high by another regulator.

How does MIC2176-2YMM implement current limiting without a sense resistor?

MIC2176-2YMM implements cycle-by-cycle current limiting by monitoring the voltage drop across the low-side MOSFET's R_DS(ON) during its ON time. The SW pin senses this voltage, compares it to a 130 mV threshold (at V_FB = 0.8 V), and triggers hiccup-mode shutdown if exceeded. This eliminates the need for a discrete sense resistor, saving board space and conduction losses-confirmed in the "Electrical Characteristics" table and "Current Limit" subsection of the datasheet.

What is the minimum off-time specification for MIC2176-2YMM, and why does it matter?

The MIC2176-2YMM has a fixed minimum off-time (t_OFF(min)) of 360 ns, which directly limits maximum duty cycle and ensures sufficient time to recharge the BST capacitor. At 200 kHz (5 µs period), this yields a maximum theoretical duty cycle of ~93%. Operating near this limit risks insufficient BST voltage, causing high-side driver failure-so designs targeting >90% duty cycle (e.g., 48 V → 5 V) must verify BST capacitor sizing and gate drive strength per the "MOSFET Gate Drive" section.

Is MIC2176-2YMM compatible with ceramic output capacitors having near-zero ESR?

No-MIC2176-2YMM requires deliberate feedback voltage ripple (20–100 mV peak-to-peak) for proper adaptive on-time triggering. Ultra-low-ESR ceramic capacitors produce insufficient ripple, so ripple injection (e.g., RC network from SW to FB) is mandatory per the "Ripple Injection" subsection. This is not optional: omission causes erratic switching or failure to regulate, as confirmed in the "Functional Description" and "Application Information" sections.