Sensor input

Digitization of the sensed signal is required to measure blood glucose levels. A digital converter (ADC) is generally used to convert the analog signal from the sensor output to a digital signal. One of the important indicators of ADC applications for accurate digital conversion is to input an appropriate level of analog signal. An op-amp for amplifying analog signals of minute sensor outputs to appropriate signal levels at the ADC input is required to make the noise performance of the op-amp itself extremely small in order to achieve high-precision amplification. It is also important to reduce the power consumption as much as possible to extend the battery operation time in blood glucose meter applications. Toshiba provides a lineup of TC75S67TU, which is an optimal CMOS operational amplifier for amplifying the sensor signals of these blood glucose meters. TC75S67TU achieves a low noise level of 6 nV/√Hz (f=1 kHz, GV=40 dB, typical) input-converted noise voltage. In addition, by adopting CMOS processing, low power dissipation is also realized at the same time.

In order to reduce the set's power consumption, a comparator may be used to detect blood to measure only when the test strip is blood applied. In this case, the power supply used as the reference voltage is required. The LDO-regulator's TCR3UG Series enables low current draw and high-precision reference voltages. TCR3UG series, which is suitable for stable system power supply, has a lineup of output voltages of 0.1V steps. Select the optimum output voltage according to the specifications of the sensors and ADCs, as well as the power supply conditions in the blood glucose meter system.

Static electricity tends to penetrate the sensor and other externally exposed parts. To avoid damage caused by this, Toshiba's high-IPP TVS diodes (ESD protection diodes) can be used to suppress from a few ns-order to ms-order ESD and transient voltages. In order to miniaturize the circuit due to the growing demand for smaller enclosures, those products have small packages options. In addition, it has been certified for IEC61000-4 series, so it is possible to provide a simpler and stronger protective circuit than ever before.

Examples of typical recommended products are listed below, and also provide a link to the online distributor inventory search page to buy the product.

Toshiba offers low-noise-type, ultra-low-current-consumption-type, and input/output full-range-type (Input/Output Rail-to-Rail) products.

Toshiba LDO regulators feature low noise, stable output voltage, low power consumption, and small packages. We offer various products to meet high-performance needs while satisfying local regulations.

Preventing damage or malfunction of the device due to external surge voltage, wide line-up of protection diodes ranging from one line to four lines is available in a small package, and high ESD tolerance and circuit protection performance realized by original process technology.