LED Driver and Li-Ion Circuit Design

Analogue Electronics / Power Supply Engineer – LED Driver Circuit Design & SPICE Simulation I'm seeking an experienced analogue electronics engineer to design, simulate and optimise an LED driver and Li-ion charging circuit for a compact rechargeable flashlight. The engineer will be responsible for developing the circuit schematics from the specifications provided. This is not a PCB layout or physical prototyping assignment. Essential experience: Applicants must have proven experience in analogue circuit design, particularly: DC-DC buck-boost converters and switching power supplies. Analogue feedback loops, op-amps and constant-current LED regulation. Continuous analogue dimming without PWM-based LED brightness control. SPICE circuit simulation, preferably PSpice for TI. Li-ion battery charging and power-management circuitry. This project requires an engineer experienced in designing and analysing analogue electronic circuits, not simply PCB layout or microcontroller programming. Please briefly describe a relevant circuit you have personally designed and simulated. Proposed components and specifications TI TPS63802 buck-boost converter TI TLV9001 op-amp for analogue LED current control Bourns 3310 rotary potentiometer (10kΩ) TI BQ25185 or BQ24074 Li-ion charging IC Single 14500 Li-ion battery (approximately 2.8–4.2V operating range) High-CRI white LED, approximately 300 lumens maximum Continuous analogue dimming from a very low glow to full brightness, without PWM-based LED dimming The components listed are preferred starting points. Technically justified alternatives may be proposed. Scope of work: Design complete LED driver and charging circuit schematics using the proposed components and relevant TI reference designs. Develop virtual circuit simulations using PSpice for TI and suitable manufacturer models. Test analogue dimming, LED current regulation, estimated efficiency and stability across the battery-voltage and brightness ranges. Evaluate battery charging, protection requirements and disabling the main LED during charging. Simulate the circuits separately where necessary and assess their electrical interaction. Refine the designs and recommend any necessary component changes. Required deliverables Complete circuit schematics with component values. Editable simulation files. Relevant performance graphs and results. Brief summary of findings, limitations and recommendations. Quotation and timescale Please confirm the availability of suitable simulation models, identify any significant simulation limitations and provide: A fixed-price quotation for the complete assignment. Your estimated number of working hours. Your expected completion time, including a reasonable allowance for unforeseen technical difficulties or revisions. Examples of relevant circuit design and simulation experience. Please ensure your quotation and timescale cover all the specified deliverables.