What is GreenPAK?

Many designers should be familiar with programmable logic, but what about programmable analog circuitry? This would normally take a range of voltage-controlled discrete semiconductors and DACs in order to generate the reference and control signals used in programmable analog designs. Now, analog and digital functionality can be found in a single device with a small footprint and full customization.

You can find this type of analog programmable functionality alongside programmable logic inside Renesas GreenPAK components. GreenPAK components offer a huge range of functionality in compact IC packaging, freeing up significant board space that would normally be used for complex circuitry. By combining programmable analog circuit blocks with programmable digital logic, these devices offer unique mixed-signal processing capabilities that would normally take a large number of ICs. We’ll look at how GreenPAK works, some popular applications, and how you can quickly get started developing a custom ASIC with GreenPAK.

What Is GreenPAK?

GreenPAK is a Renesas hardware and software platform for implementing custom mixed-signal circuits. The hardware consists of configurable ICs containing analog circuit blocks, digital logic blocks, and programmable interconnections. The software is the Go Configure Software Hub, which includes the legacy GreenPAK Designer development environment. Together, these tools allow engineers to consolidate functions such as voltage monitoring, timing, reset generation, and logic control into a single device.

All circuit blocks available in the selected IC are assembled graphically. Configuration data determines block settings, interconnections, and pin behavior. The resulting circuit operates in hardware, with its behavior established by those resources and settings.

Go Configure supports the development process through:

• Graphical circuit entry and routing between available blocks
• Configuration of logic functions, analog parameters, timing, and I/O
• Design rule checking and circuit simulation
• Hardware emulation, testing, and device programming through compatible development boards
• Example projects and supporting documentation

GreenPAK includes one-time and multiple-time programmable products, so programming capability must be checked against the selected part’s datasheet. For example, the SLG46826 combines an I2C interface, multiple-time programmable memory, comparators, timing blocks, and dual-supply operation.

What Can You Build With GreenPAK?

GreenPAK serves applications where several analog, timing, and logic functions must operate together. In embedded systems, these include supply sequencing, reset generation, watchdog timing, and wake/sleep control. Consumer products and portable electronics can use the same resources for button qualification, battery indication, LED patterns, and peripheral control. Consolidating these functions can reduce the number of support ICs around a processor while keeping the required control behavior in dedicated hardware.

Sensor interfaces are another common application. For example, comparators can quantize analog signal levels and apply a logic state based on the signal amplitude, while the downstream logic blocks provide logical processing functions based on this amplitude reading and additional inputs. The ability to apply logical processing based on analog sensor readings would normally require an ADC and a routine in firmware, but this is much simpler with a dedicated GreenPAK device.

Timed Reset Sequencing for Multiple Controllers

A system containing two controllers may require one controller to initialize before the second starts. A GreenPAK device can establish this order using an internal oscillator, counter/delay blocks, and separate reset outputs. Each output releases its controller after a configured interval, giving the first controller time to establish its role.

The power sequencing with GreenPAK example implements this behavior with an SLG46826V and two ATmega328P devices. Open-drain outputs connect to the reset inputs, and simulation verifies the release times before hardware testing. Supply monitoring can be incorporated when startup must depend on external rail validity as well as elapsed time.

A Hardware and Software Platform

GreenPAK Devices

The hardware side of GreenPAK consists of ICs with different combinations of configurable analog, digital, interface, and power resources. GreenPAK devices combine a configurable connection matrix with function blocks, called “macrocells.” Depending on the selected device, integrated capabilities include:

• Analog comparators, voltage references, switches, and signal-conditioning blocks.
• Lookup tables, flip-flops, latches, and state-control resources.
• Oscillators, counters, delays, and pattern-generation functions.
• Configurable I/O, I2C or SPI interfaces, and voltage-domain interfacing.
• ADCs, operational amplifiers, or programmable resistances.
• Voltage regulation or motor-drive functions in applicable product families.

Integration reduces the chip count when several required functions fit within one device. Small packages, including the SLG46826V’s 2 mm × 3 mm package, also reduce the area occupied by support circuitry and its interconnections. Go Configure’s graphical tools make development accessible through block configuration and routing, allowing engineers to revise thresholds, timing, and logic while evaluating the same selected hardware.

To find the right GreenPAK part number for your application, visit the GreenPAK Product Selector page.

Go Configure Software Hub

Go Configure Software Hub provides the development environment for GreenPAK devices. After selecting a target device, development is performed graphically by connecting available circuit blocks and configuring their parameters. Simulation supports evaluation before hardware testing, while compatible development boards provide emulation and programming. The Go Configure walkthrough also demonstrates design rule checking and comparison of configuration revisions.

The installers are available from the Go Configure Software Hub downloads page. Renesas provides versions for Windows, macOS, and supported Linux distributions.

The GreenPAK Cookbook

The GreenPAK Cookbook is a collection of circuit techniques and application examples built around the device family’s configurable resources. It shows how individual macrocells, or small groups of blocks, implement useful functions. Common examples include power sequencing, system resets, timing circuits, and motor control, providing starting points for the support circuitry found around embedded processors and other subsystems.

The examples can be easily recreated in Go Configure to start a new design, and downloadable design files allow engineers to inspect and modify existing configurations directly. The GreenPAK tutorial provides additional context for moving from a graphical circuit to simulation and hardware evaluation.

The guide and associated resources are available from the GreenPAK Cookbook downloads page. The accompanying design files provide editable starting points for application development.

Get Started With GreenPAK Developer Kits

The SLG4DVKADV GreenPAK Advanced Development Board provides programming, emulation, and test functions for supported GreenPAK devices. The board requires a compatible device-specific socket adapter, ordered separately, and samples of the selected IC. Its USB interface connects to Go Configure, while onboard signal generators, logic generators, LEDs, and external test connections support circuit evaluation.

Ready to streamline your board design and consolidate complex mixed-signal functions into a single compact device? Download the Go Configure Software Hub to begin building and simulating your custom ICs graphically. Browse the GreenPAK Cookbook for ready-to-use application examples, power sequencing circuits, and logic designs that you can customize directly. Once your design is ready, order an SLG4DVKADV Advanced Development Board to test, emulate, and program your custom mixed-signal circuits in hardware.