ROHM Smart Thermal Printhead STPH

ROHM's STPH (Smart Thermal Printhead) series printhead is a core component based on thermal printing technology, which is widely used in ticket printing, label printing, medical equipment, industrial marking and other fields. The following is a comprehensive introduction from two aspects: working principle and technical advantages:

1. Working principle of STPH printhead

ROHM STPH series adopts thermal printing technology. Its core principle is to produce local chemical reaction on thermal paper by precisely controlling the micro heating elements (heating points) on the printhead to form images or text. The specific process is as follows:

Data input

The printhead receives the signal (digital data) from the control circuit to determine the position of the pixel point that needs to be heated.

Heating element activation

The resistive heating element on the printhead (usually composed of high-density heating points) heats up instantly under the action of electric current (microsecond response), and the heat is transferred to the surface of thermal paper.

Thermosensitive reaction color development

The coating of thermal paper reacts chemically at high temperature, and the color development area forms the required pattern or text (no ink or carbon ribbon is required).

Line-by-line printing

The entire page is printed line by line through the lateral movement of the mechanical structure or paper feeding.

2. Technical advantages of ROHM STPH printhead

As a leading company in the field of semiconductors and electronic components, ROHM's STPH series has the following outstanding advantages in design and performance:

1. High resolution and print quality

High-density heating points: The STPH series uses micro-machining technology, and the density of heating elements can reach 200-300 dpi (some models support higher), which is suitable for printing fine text, barcodes or complex graphics.

Grayscale control: Precisely control the heating time and temperature through pulse width modulation (PWM) to achieve multi-level grayscale output and enhance the layering of the image.

2. High-speed response and durability

Low thermal capacity design: The heating element uses low thermal capacity material, with fast heating/cooling speed, and supports high-speed continuous printing (such as ticket printers can reach 200-300 mm/s).

Long life: ROHM's semiconductor process ensures the anti-aging performance of the heating element, and the typical life can reach a printing distance of more than 50 kilometers (depending on the model).

3. Energy saving and thermal management

Efficient driving circuit: built-in optimized driving IC, reducing power consumption (some models support low voltage driving, such as 3.3V or 5V), reducing energy waste.

Temperature compensation technology: automatically monitors ambient temperature and adjusts heating parameters to avoid blurry printing or thermal paper damage caused by overheating.

4. Compact and integrated design

Modular structure: the print head and driving circuit are highly integrated, reducing the number of external components and simplifying equipment design.

Thin appearance: suitable for space-constrained application scenarios (such as portable printers or medical equipment).

5. Reliability and compatibility

Wide compatibility: supports a variety of thermal paper types (including two-color paper) to meet the needs of different industries.

Anti-interference design: built-in ESD protection circuit to prevent electrostatic damage and improve stability in industrial environments.

6. Environmental protection and low maintenance

Ink-free design: thermal printing does not require carbon ribbon or ink, reducing consumables replacement and environmental pollution.

Self-cleaning function: some models support automatic cleaning mode to prevent paper scraps or dust accumulation.

III. Typical application scenarios

Retail and catering: POS machine receipt printing.

Logistics and warehousing: label and waybill printing.

Medical equipment: ECG, ultrasound report output.

Industrial marking: production date, batch number printing.

IV. Summary

ROHM STPH series print heads have become the preferred solution in the field of thermal printing due to their high precision, high speed, low power consumption and long life. Its core technical advantage lies in the deep integration of semiconductor process and thermal management, which can meet the diverse needs from consumer to industrial level, while reducing the comprehensive cost of use for users. For equipment manufacturers who need reliable and efficient printing, the STPH series provides a highly optimized solution