Chandler, Ariz. -- Cactus Semiconductor has updated its microprocessor evaluation board for its application-specific standard product (ASSP) medical chip to deliver better manufacturability and a lower profile. The update includes new microcontroller (MCU) unit packaging for easier manufacturability, and new inductors for a lower profile. The EB1CSI021 evaluation board targets battery-powered neurostimulation medical applications.
The low-power, 8-bit MCU now uses an ultra-fine pitch, quad flat no-lead 28-pin (UFQFPN28) package. By replacing the previous WLCSP package, the new design improves manufacturability and simplifies reworking, said Cactus. The small 4- x 4-mm MCU footprint and ultra-low power make the ASSP well suited for implantable medical applications, including neurostimulation / neuromodulation, MEMs and sensor applications, and implantable pulse generators (IPG).
The inductors on the board were also changed for the dual boost converter, which delivers a lower profile and smaller footprint for end product designs. The inductors can offer a four times footprint reduction compared to the original inductors, according to the company.
The new board also adds a jumper to separate the MCU power supply from the on-board LDO. This is to increase design and power management flexibility allowing the user to bypass the fixed LDO output voltage, said Cactus.
The evaluation board is provided with two Cactus Semiconductor CSI021 medical ASSPs that can be synchronized. The CSI021 ASSPs feature four independent 8-bit linear DAC programmable current sink/source outputs. They deliver up to a 6-mA full-scale sink and 1.5-mA full-scale source currents. Full-scale current ranges are programmable via an external reference resistor. An 18-V supply voltage allows for 6-mA output currents into 1.5-kohm loads.
The CSI021 pulse timing is fully programmable via a 1 MHz (up to 10 MHz) 2.5-V SPI. The ASSP can be programmed via the MCU using the SPI. Optionally the SPI can be externally controlled, bypassing the MCU, to program the ASSP directly. Programmable parameters include sink/source pulse widths, pulse frequencies, stimulation on/off periods, and amplitude ramp rates.
For medical applications, internal timing generators in the CSI021 use the programmed parameters to create therapy profiles, which is accomplished with only minimal intervention from a host processor, said Cactus. A 4:1 sink-to-source current ratio provides for easy stimulation charge balancing.
Availability: The EB1CSI021 evaluation board and CSI021 ASSP are now available for purchase via the company's website.
Pricing: The evaluation board is priced at $956.46 while the ASSP is priced at $391. To purchase in mass quantities, parties are advised to first contact the company's sales department. Contact information and a data sheet for both devices can be found at the company website.