Monolithic Power Systems Inc. MP1497SGJ-P

Overview

MP1497SGJ-P from Monolithic Power Systems is a synchronous step-down DC/DC converter IC with integrated 120mΩ high-side and 50mΩ low-side MOSFETs, delivering up to 3A continuous output current across a 4.5V–16V input range, fixed 500kHz switching frequency, and adjustable 0.8V–VIN×0.95 output voltage - deployed in notebook I/O power and flat-panel display supplies.

For engineers reviewing the MP1497SGJ-P datasheet, MP1497SGJ-P pinout, MP1497SGJ-P application, or MP1497SGJ-P equivalent, key selection criteria include internal MOSFET R_DS(on), external clock synchronization capability (300kHz–2MHz), programmable soft-start via SS pin, hiccup-mode over-current protection, and thermal shutdown at 150°C.

Technical Context

The MP1497SGJ-P employs peak-current-mode control with a fixed 500kHz oscillator and supports external clock synchronization via the EN/SYNC pin. Its proprietary switching-loss-reduction technique enhances efficiency across load conditions while maintaining stable loop response through an internally compensated error amplifier referenced to 0.807V.

It integrates a 5V VCC regulator powered from VIN, a bootstrap circuit for high-side gate drive (BST pin), and cycle-by-cycle over-current protection triggered at 4.2A typical. Thermal shutdown activates at 150°C with 20°C hysteresis, and UVLO engages at 3.9V rising threshold with 650mV hysteresis.

Key Specifications

Pinout & Package

MP1497SGJ-P is housed in an 8-pin TSOT23 package (3.0mm × 3.0mm × 0.9mm), optimized for high-density PCB layouts and thermally constrained applications. The exposed pad variant (GJ) enhances thermal dissipation via PCB copper area connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP1497SGJ-P, MP2315GJ-Z trades synchronization capability for higher frequency and smaller inductors, while RT7297CGJ8 provides lower V_FB and EMI features at the cost of pin compatibility and design reuse.

Availability

MP1497SGJ-P is available at Aetrix Electronics and suitable for notebook I/O power, flat-panel display logic supplies, and distributed telecom power applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP1497SGJ-P 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with design centers across Asia and North America.

The MP1497S product line delivers highly integrated, thermally efficient synchronous buck converters targeting space- and efficiency-critical consumer and industrial power systems.

FAQ

What is the maximum recommended output current for MP1497SGJ-P under continuous operation?

The MP1497SGJ-P is rated for 3A continuous output current under specified thermal conditions (TA = 25°C, θJA = 100°C/W, adequate PCB copper). Derating is required above 85°C ambient or with insufficient thermal relief; full 3A load assumes ≥2 cm² of 2-oz copper connected to the exposed pad.

Can MP1497SGJ-P synchronize to an external clock, and what are the valid frequency and signal requirements?

Yes - the EN/SYNC pin accepts a clean CMOS-level clock from 300kHz to 2MHz. The external clock must have pulse width <1.7µs and rise/fall times ≤10ns. Synchronization begins ~2ms after enable, aligning internal clock rising edges to external clock rising edges.

How does the hiccup-mode over-current protection behave during a sustained short-circuit condition?

Upon detecting current limit violation, MP1497SGJ-P enters hiccup mode: it disables switching for ~30ms, then attempts restart. If fault persists, it repeats the cycle. Average short-circuit current drops to ~200mA, limiting power dissipation and preventing thermal damage without requiring external latch-off circuitry.

What is the purpose of the BST pin, and what capacitor value is recommended between BST and SW?

The BST pin supplies the floating gate drive for the internal high-side MOSFET. A 0.1µF ceramic capacitor (X5R/X7R, 10V rating) must be placed between BST and SW. A 10Ω resistor in series with this capacitor is strongly recommended to dampen SW node ringing and reduce EMI.

Is an external bootstrap diode required, and when does it improve efficiency?

An external bootstrap diode (e.g., IN4148) from VCC to BST is optional but beneficial when VOUT ≥3.3V and duty cycle >65% (i.e., VIN/VOUT > 1.5). It reduces BST capacitor charging losses and improves efficiency by ~1–2% under heavy load at high duty cycles.

What is the minimum output voltage achievable with MP1497SGJ-P, and how is it set?

The minimum regulated output voltage is 0.807V, set by the internal feedback reference. It is achieved using a resistor divider where R2 connects FB to GND and R1 connects VOUT to FB. For example, a 3.3V output uses R1 = 40.2kΩ and R2 = 13kΩ per MPS Table 1.

Does MP1497SGJ-P support output voltages above its input voltage?

No - MP1497SGJ-P is a step-down (buck) converter only. Its maximum output voltage is limited to VIN × DMAX ≈ VIN × 0.95. Attempting to set VOUT > VIN will result in regulation failure and uncontrolled operation; it cannot function as a boost or buck-boost regulator.