RK3188-SOM - Quad Core Cortex-A9 SoM, 1GB DDR3 | Olimex
MPN: RK3188-SOM ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $49.5 | $49.50 |
| 10 | $45 | $450.00 |
| 50 | $41 | $2,050.00 |
| 100 | $38.5 | $3,850.00 |
| 250 | $35 | $8,750.00 |
RK3188-SOM Overview
What is a System-on-Module (SoM)? A SoM is a small board that integrates the core computing components of an embedded system - processor, RAM, PMIC, and boot media - into a single, tested unit that a baseboard can host through high-density board-to-board connectors. SoMs sit in the embedded hierarchy between bare System-on-Chip (SoC) designs (where the integrator places the SoC and DRAM directly on the application board) and full single-board computers (SBCs). The benefit is design reuse: hardware teams can iterate on the application baseboard without re-validating memory, power, and clock trees.
Key features of the RK3188-SOM include the Mali-400 MP4 GPU supporting OpenGL ES 1.1/2.0, hardware 1080p H.264 video decode and encode, USB 2.0 OTG and host, I2C/SPI/UART/I2S peripherals brought out through the connectors, and boot from the on-module SD-card socket. The integrated AC8846 PMIC generates all the processor and DDR rails from a single external supply, simplifying baseboard design.
Typical applications include Android-based tablets and digital signage, kiosk displays, industrial HMI panels, and prototype media players. The wide signal availability on the connectors also makes the module attractive for firmware bring-up, OS porting (Linux/Android), and education labs needing a deterministic Cortex-A9 quad-core platform.
When designing with the RK3188-SOM, ensure the mating baseboard connectors are rated for the 0.05-inch (1.27 mm) pitch and that baseboard decoupling is sized for the in-rush current of the AC8846 PMIC during cold boot. The legacy RK3188 silicon and Android 4.x-era software stack are now considered end-of-life for new consumer designs; choose the RK3288-SoM or RK3566-based modules for new projects requiring long-term OS support.
This page synthesizes distributor pricing across DigiKey and Mouser, parameter-by-parameter comparison against related Rockchip SoMs, and practical baseboard design notes - engineering content not present in the manufacturer user manual.
Drop-in alternatives for RK3188-SOM — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with RK3188-SOM (same form factor and footprint) — differing in Expansion Connectors, Mounting Type, Operating Systems, Power Management IC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
RK3188-SOM-4GB
✅ Drop-In✓ In Stock
$23.97 / Unit
View Datasheet →A20-SOM
✅ Drop-In📋 Reference alternative (not in catalog)
A13-SOM
✅ Drop-In📋 Reference alternative (not in catalog)
RK3188-SOM Specifications (manufacturer-published)
| Processor | Rockchip RK3188 |
| CPU Architecture | ARM Cortex-A9, quad-core, 32-bit |
| Maximum CPU Frequency | 1.6 GHz |
| GPU | ARM Mali-400 MP4 |
| On-board RAM | 1 GB DDR3 |
| Power Management IC | Actions Semiconductor AC8846 |
| Expansion Connectors | 5 x 40-pin headers, 0.05 inch (1.27 mm) pitch |
| Storage Interface | SD-card socket (on-module) |
| Debug Interface | UART console connector |
| USB | USB 2.0 OTG and USB 2.0 Host (via baseboard) |
| Video Decode | 1080p H.264 hardware decode |
| Video Encode | 1080p H.264 hardware encode |
| Operating Systems | Android 4.x, Linux (vendor BSP) |
| Form Factor | SoM (System-on-Module) |
| Mounting Type | Board-to-board header (baseboard mount) |
RK3188-SOM Interfaces & Connectors
RK3188-SOM exposes the following interfaces and connectors as published by the manufacturer: USB. Expansion header pinout, connector pin numbering, and electrical limits are defined in the manufacturer documentation.
| USB | USB 2.0 OTG and USB 2.0 Host (via baseboard) |
Refer to the manufacturer documentation for the full expansion header pinout and connector pin numbering.
Typical Applications
RK3188-SOM is suitable for 6 applications: Android Tablet Reference Design, Digital Signage and Kiosk Displays, Industrial HMI Panels, Set-Top Box and Media Player Prototyping, Linux/Android BSP Development and Education, Legacy Embedded Product Maintenance.
Android Tablet Reference Design
The RK3188-SOM's quad-core Cortex-A9 at 1.6 GHz with Mali-400 MP4 GPU and 1080p H.264 hardware decode directly targets Android tablet designs of the 2013-2016 era. The on-module 1 GB DDR3 matches the memory budget of Android 4.4 KitKat tablets, and Olimex's Android BSP provides touch, display, and Wi-Fi drivers on the EVB. Engineers designing reference tablets benefit from the five 0.05-inch connectors exposing every SoC signal - LCD, touch, camera, and battery management - so a custom baseboard can be tuned without re-validating the SoC, PMIC, or DRAM. Note that Android 4.x is end-of-life; new tablet designs should target RK3566-based SoMs.
Recommended
Digital Signage and Kiosk Displays
The RK3188-SOM drives 1080p H.264 video decode hardware at low power, making it well-suited to fanless digital signage and kiosk display designs where reliability and long-running cost matter more than peak CPU. The module's exposed display interfaces (LVDS/RGB/HDMI via baseboard) connect directly to commercial LCD panels, and the on-module AC8846 PMIC simplifies thermal design to a single 5 V input. The Mali-400 MP4 GPU accelerates OpenGL ES 2.0 for interactive kiosk UIs. Compared with newer RK3566 designs, the RK3188-SOM lacks HEVC and modern security features but delivers mature, stable firmware that many kiosk integrators still maintain in production fleets.
Recommended
Industrial HMI Panels
Industrial human-machine interface (HMI) panels benefit from the RK3188-SOM's quad-core performance, exposed GPIO and UART headers, and robust connector pitch (0.05 inch) that suits industrial vibration profiles. The module mounts to a baseboard hosting a touch LCD, RS-485 transceivers, and isolated digital I/O - all powered from a single 5 V rail via the on-module AC8846 PMIC. Engineers building factory-floor HMIs value the deterministic boot from the on-module SD-card socket, which simplifies firmware updates and ruggedization. Lifecycle risk: the RK3188 silicon is in last-time-buy status, so new industrial HMI programs should qualify the RK3566-SoM or i.MX8M-based SoMs that offer formal 10-year longevity programs.
Recommended
Set-Top Box and Media Player Prototyping
The RK3188-SOM is well-suited for prototyping Android- or Linux-based set-top boxes and media players: 1080p H.264 hardware decode drives full-HD content smoothly, the Mali-400 MP4 GPU handles 2D UI composition, and the exposed I2S bus connects to external DACs for audio playback. The on-module SD-card socket enables firmware and media storage without baseboard eMMC design. The Olimex EVB provides HDMI, optical S/PDIF, and analog audio outputs that mirror typical STB reference designs. For commercial STB production, plan migration to RK3566/RK3588 SoMs that add HEVC and HDR support - the RK3188 is sufficient only for legacy SD/HD H.264 content.
Recommended
Linux/Android BSP Development and Education
The RK3188-SOM is widely used in embedded Linux and Android training labs because every processor signal is exposed through the five 0.05-inch connectors, enabling students to probe and instrument the SoC without specialized debug fixtures. The UART console header simplifies bootloader (U-Boot) and kernel debugging. Olimex provides a vendor BSP and the RK3188-SOM-EVB which mirrors the connectors in a breadboard-friendly layout, making it well-suited for coursework on ARM Cortex-A9 architecture, GPU programming (OpenGL ES), and board bring-up labs. Universities should note that long-term availability is limited; pair with the RK3566-SoM for future-proofed curricula.
Recommended
Legacy Embedded Product Maintenance
Many industrial and consumer products shipped between 2013 and 2018 used the RK3188-SOM and now require spare modules for warranty repair and field replacement. Distributors like Components-House.com and Micro-Semiconductor list legacy stock that supports these maintenance workflows. Engineers in this scenario should verify authenticity against Olimex lot codes and prefer authorized distributor channels. For products transitioning to new silicon, the RK3188-SOM-4GB is the closest drop-in module, doubling on-board DDR3 without changing the baseboard. Long-term, plan a baseboard redesign around RK3566 or i.MX8M SoMs that offer formal longevity commitments.
Recommended
Recommended Products Summary
Engineering reference data for RK3188-SOM — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | RK3188-SOM-4GB | A20-SOM | A13-SOM |
|---|---|---|---|---|
| Brand | Olimex | Olimex | Olimex | Olimex |
| Package | SoM, 5 x 40-pin 0.05" connectors | SoM, 5 x 40-pin 0.05" connectors - same | SoM, 5 x 40-pin 0.05" connectors - same Olimex SoM family | SoM, 5 x 40-pin 0.05" connectors - same Olimex SoM family |
| Processor | Rockchip RK3188 (Cortex-A9 quad-core) | Rockchip RK3188 (Cortex-A9 quad-core) - same die | Allwinner A20 (Cortex-A7 dual-core) | Allwinner A13 (Cortex-A8 single-core) |
| Maximum CPU Frequency | 1.6 GHz | 1.6 GHz - same | 1.0 GHz | 1.0 GHz |
| On-board RAM | 1 GB DDR3 | 4 GB DDR3 (+300%) | 1 GB DDR3 | 512 MB DDR3 |
| GPU | Mali-400 MP4 | Mali-400 MP4 - same | Mali-400 MP2 | Mali-400 |
| PMIC | Actions AC8846 | Actions AC8846 - same | AXP209 | AXP209 |
| Expansion Connectors | 5 x 40-pin, 0.05" pitch | 5 x 40-pin, 0.05" pitch - same | 5 x 40-pin, 0.05" pitch - same Olimex SoM family | 5 x 40-pin, 0.05" pitch - same Olimex SoM family |
Key Differentiators
- Highest per-module CPU performance in the legacy Olimex SoM family (vs A20-SOM)
- Quad-core vs single-core for parallel workloads (vs A13-SOM)
- Native RK3188 silicon compatibility for legacy designs (vs RK3188-SOM-4GB)
Design Notes
The RK3188-SOM is powered through the baseboard connector pin-out; Olimex specifies a single 5 V input that the on-module AC8846 PMIC converts to all processor and DDR3 rails. When laying out the baseboard, place a low-ESR 22 uF bulk capacitor within 10 mm of the module's 5 V input pins to absorb the PMIC's cold-boot in-rush, which can momentarily exceed 2 A. Verify your baseboard's 5 V regulator can sustain 3 A continuous; the RK3188 plus DDR3 plus Mali-400 MP4 GPU peaks near 4 W under H.264 decode workloads.
The RK3188 SoC has no on-module heatsink. Under sustained 1080p H.264 decode with all four Cortex-A9 cores active, junction temperature can rise 30-40 C above ambient. Estimated: at T_ambient 25 C, sustained load yields T_junction ~ 65-75 C, below the 85 C limit. For enclosed kiosk or industrial HMI enclosures, provide at least 200 cm^2 of passive copper pour on the baseboard beneath the SoM, or add a 15 mm aluminum spreader, to maintain margin across the full -10 C to +60 C industrial range.
The five 0.05-inch (1.27 mm) pitch headers are the only mechanical and electrical interface. Use Samtec FTSH or equivalent shrouded, polarized headers on the baseboard to prevent mis-mating; the modules ship without keys, so pin-1 dot orientation must be silk-screened on both sides. Maintain at least 8 mm of baseboard keep-out under the SoM for the AC8846 PMIC thermal relief, and route all high-speed display and USB differential pairs with 90 ohm differential impedance, length-matched within 150 mils.
Common pitfalls when using the RK3188-SOM include: (1) assuming Android 4.x firmware will boot on newer BSPs - the boot loader expects a specific partition table on the SD-card; (2) routing USB DP/DN without 90 ohm impedance, causing enumeration failures; (3) forgetting to level-shift the I2C bus to 3.3 V when connecting 5 V peripherals - the RK3188 I/O is 3.3 V tolerant only; (4) omitting the on-module SD-card socket's pull-ups on the CMD and DAT lines, leading to sporadic boot failures. Always power-cycle the module after firmware updates to clear the AC8846 PMIC fault latches.
Compliance Information
Compliance status not stated on the Olimex product page or Mouser/DigiKey listings included in the verified web data. The RK3188-SOM is a System-on-Module designed for evaluation and prototyping, not a finished consumer product, so formal compliance certifications are typically the responsibility of the integrator baseboard.