Diodes Incorporated AP3917BS7-13

Overview

AP3917BS7-13 from Diodes Incorporated is a universal AC-input step-down power switcher integrating a 650V Power MOSFET in SO-7 package, designed for non-isolated buck and offline flyback topologies in home appliances and IoT systems. It delivers ±5% constant voltage regulation, supports 85–300VAC input, achieves <30mW no-load power consumption with external bias, and provides 280mA typical peak current for up to 170mA rated output current.

For engineers reviewing the AP3917BS7-13 datasheet, AP3917BS7-13 pinout, AP3917BS7-13 application, or AP3917BS7-13 equivalent, key selection criteria include universal AC input handling, integrated high-voltage MOSFET, light-load efficiency optimization via frequency/peak-current reduction, thermal and open-loop protection thresholds, and SO-7 thermal performance (θJA = 95°C/W).

Technical Context

The AP3917BS7-13 implements a self-supplied, current-mode PWM controller with internal 650V MOSFET and adaptive frequency modulation. Its VBP supply is managed by an internal HV regulator with hysteresis (VBP_HVOFF = 8.5V, VBP_HVON = 8.2V), enabling automatic start-up and fault-triggered latch-off with restart at 4.5V.

It uses FB-pin feedback for constant-voltage regulation (VFB = 2.5V threshold) and integrates multiple protections: OTP (T_OTP = +150°C), OLP (VFB_OLP = 1.7V, t_OLP = 170ms @36kHz), SCP (ISCP = 390mA), and open-loop detection (VOLD = 60mV). Peak current and switching frequency scale downward under light load to suppress audible noise and improve efficiency.

Key Specifications

Pinout & Package

The AP3917BS7-13 is housed in a 7-pin SO-7 package (JEDEC MS-012 variant), with matte tin-plated leads, MSL Level 3 moisture sensitivity, and 0.077g mass. Pins 1 and 2 are internally unconnected but recommended to be tied to source for thermal enhancement.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar universal AC-input step-down power switcher applications.

Compared with AP3917BS7-13, AP3915BS7-13 sacrifices light-load efficiency and open-loop safety for lower unit cost, while MP174GJ-Z trades integrated protection for higher current capability and lower R_DS(ON), demanding added design effort for system-level reliability.

Availability

AP3917BS7-13 is available at Aetrix Electronics and suitable for non-isolated home appliances, IoT edge devices, and industrial control panels requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for AP3917BS7-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in power management, signal integrity, and protection solutions for high-volume industrial and consumer markets.

The AP3917B belongs to Diodes' AC-DC primary-side switcher product line, engineered specifically for cost-sensitive, space-constrained non-isolated and flyback power supplies in home appliance and smart device applications.

FAQ

What is the minimum external bypass capacitor value required on the BP pin?

The BP pin requires a minimum 10µF electrolytic or tantalum capacitor rated ≥16V. This value ensures stable startup and sufficient energy storage during fault latch-off; smaller values cause erratic restart behavior or failure to initiate regulation. The capacitor must be placed within 5mm of the BP pin with low-ESR construction to maintain control loop stability.

Can AP3917BS7-13 operate in continuous conduction mode (CCM)?

Yes - the AP3917BS7-13 supports both discontinuous (DCM) and continuous conduction mode (CCM) operation depending on inductor value, load, and input voltage. CCM is enabled when inductor ripple current remains above zero; the device automatically adjusts off-time to maintain regulation, with CCM equations provided in Section 8 of DS41277 Rev. 8-2.

How does the open-loop protection function during startup?

Open-loop protection is blanked for 64 switching cycles after power-on to prevent false triggering during initial output ramp-up. After this blanking period, if FB voltage remains below 60mV (indicating missing or faulty feedback network), the device stops switching and enters auto-restart mode with BP discharge to 4.5V before attempting recovery.

Is the SO-7 package lead-free and RoHS-compliant?

Yes - the AP3917BS7-13 is fully lead-free and complies with EU RoHS Directive 2015/863/EU (RoHS 3), containing <900ppm bromine, <900ppm chlorine, and <1000ppm antimony compounds. Matte tin plating meets JESD22-B102 Method 208 solderability requirements and MSL Level 3 per J-STD-020.