CY8C3866PVI-021 - PSoC 3 8051 64KB Flash 67MHz MCU | Infineon
MPN: CY8C3866PVI-021 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.2 | $6.20 |
| 10 | $5.62 | $56.20 |
| 100 | $4.95 | $495.00 |
| 500 | $4.3 | $2,150.00 |
| 1,000 | $3.85 | $3,850.00 |
| 3,000 | $3.4 | $10,200.00 |
CY8C3866PVI-021 Overview
What is a PSoC? PSoC (Programmable System-on-Chip) is a family of microcontrollers that integrate a CPU core (8051, ARM Cortex-M0/M3/M4 depending on generation) with a programmable analog and digital fabric. PSoC 3 is the 8-bit 8051-based generation, while PSoC 4 (Cortex-M0), PSoC 5LP (Cortex-M3), and PSoC 6 (Cortex-M4 + M0+) are the more recent families. PSoC 3 sits in the hierarchy: PSoC 3 -> PSoC family -> programmable SoC -> microcontroller -> embedded IC -> semiconductor. The configurable fabric allows routing of analog blocks (op-amps, ADCs, DACs, comparators) and digital blocks (timers, UARTs, SPIs, PWMs) via on-chip interconnect, replacing many discrete components.
Key features of the CY8C3866PVI-021 include 24 Universal Digital Blocks (UDBs), 4 DMA channels with a Peripheral Hub Unit (PHUB) providing 8 parallel access spokes, a 67 MHz maximum CPU clock, 27 interrupt sources with 8 priority levels, integrated Full-Speed USB 2.0, and 4 levels of Flash protection. The IC also integrates a 20-bit Delta-Sigma ADC plus a 12-bit SAR ADC, two 8-bit IDACs, four 7-bit VDACs, and four unity-gain op-amps configurable as PGAs, TIA, or comparators. Up to 62 GPIO are available depending on package.
Typical use cases for the CY8C3866PVI-021 include industrial motor and pump drivers, USB-enabled embedded peripherals, smart sensors and CapSense touch interfaces, programmable logic replacements, mixed-signal data acquisition front-ends, and human-machine interface (HMI) panels. When designing with this part, note that the 8051 core is 8-bit and slower than modern Cortex-M alternatives, but the integrated analog fabric and Infineon/Cypress PSoC Creator toolchain accelerate development of mixed-signal products where analog pins are a priority. For pure digital or low-power designs, an ARM-based PSoC 4/6 is usually a better choice.
This page synthesizes distributor pricing, drop-in alternatives in the same 48-SSOP package, and practical design notes that go beyond the manufacturer datasheet alone.
Drop-in alternatives for CY8C3866PVI-021 — 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 CY8C3866PVI-021 (same form factor and footprint) — differing in Package, ADC, Mounting Type, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
CY8C3866PVI-021T
✅ Drop-In📋 Reference alternative (not in catalog)
CY8C3446PVI-102
✅ Drop-In📋 Reference alternative (not in catalog)
CY8C3246PVI-122
✅ Drop-In📋 Reference alternative (not in catalog)
CY8C3866AXI-040
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.8 / Unit
View Datasheet →CY8C3866AXI-035
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$9.3 / Unit
View Datasheet →CY8C3866PVI-021 Maximum Ratings & Electrical Characteristics
| Product Family | PSoC 3 (CY8C38xx) |
| CPU Core | 8051, single-core |
| Maximum CPU Clock | 67 MHz |
| Program Memory (Flash) | 64 KB (64K x 8) |
| SRAM | 8 KB |
| EEPROM (Emulated) | 1 KB |
| Operating Voltage Range | 0.5 V to 5.5 V |
| Data Bus Width | 8-bit |
| ADC | 20-bit Delta-Sigma + 12-bit SAR |
| Universal Digital Blocks (UDBs) | 24 |
| DMA Channels | 4 (with 8-spoke PHUB) |
| USB | USB 2.0 Full-Speed |
| GPIO Count (max) | 62 |
| Package | 48-pin SSOP |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (industrial) |
| RoHS Status | Compliant |
CY8C3866PVI-021 Pin Configuration
| Pin 1 | P2[0] — GPIO port 2 bit 0 / analog mux |
| Pin 2 | P2[1] — GPIO port 2 bit 1 / analog mux |
| Pin 3 | P2[2] — GPIO port 2 bit 2 / analog mux |
| Pin 4 | P2[3] — GPIO port 2 bit 3 / analog mux |
| Pin 5 | P2[4] — GPIO port 2 bit 4 / analog mux |
| Pin 6 | P2[5] — GPIO port 2 bit 5 / analog mux |
| Pin 7 | P2[6] — GPIO port 2 bit 6 / analog mux |
| Pin 8 | P2[7] — GPIO port 2 bit 7 / analog mux |
| Pin 9 | VDDA — Analog supply |
| Pin 10 | AGND — Analog ground |
| Pin 11 | P3[0] — GPIO port 3 bit 0 |
| Pin 12 | P3[1] — GPIO port 3 bit 1 |
| Pin 13 | P3[2] — GPIO port 3 bit 2 |
| Pin 14 | P3[3] — GPIO port 3 bit 3 |
| Pin 15 | P3[4] — GPIO port 3 bit 4 |
| Pin 16 | P3[5] — GPIO port 3 bit 5 |
| Pin 17 | P3[6] — GPIO port 3 bit 6 |
| Pin 18 | P3[7] — GPIO port 3 bit 7 |
| Pin 19 | VSS — Digital ground |
| Pin 20 | VDDD — Digital supply |
| Pin 21 | P4[0] — GPIO port 4 bit 0 |
| Pin 22 | P4[1] — GPIO port 4 bit 1 |
| Pin 23 | P4[2] — GPIO port 4 bit 2 |
| Pin 24 | P4[3] — GPIO port 4 bit 3 |
| Pin 25 | P4[4] — GPIO port 4 bit 4 |
| Pin 26 | P4[5] — GPIO port 4 bit 5 |
| Pin 27 | P4[6] — GPIO port 4 bit 6 |
| Pin 28 | P4[7] — GPIO port 4 bit 7 |
| Pin 29 | P5[0] — GPIO port 5 bit 0 |
| Pin 30 | P5[1] — GPIO port 5 bit 1 |
| Pin 31 | P5[2] — GPIO port 5 bit 2 |
| Pin 32 | P5[3] — GPIO port 5 bit 3 |
| Pin 33 | P5[4] — GPIO port 5 bit 4 |
| Pin 34 | P5[5] — GPIO port 5 bit 5 |
| Pin 35 | P5[6] — GPIO port 5 bit 6 |
| Pin 36 | P5[7] — GPIO port 5 bit 7 |
| Pin 37 | VSS — Digital ground |
| Pin 38 | VDDD — Digital supply |
| Pin 39 | P0[0] — GPIO port 0 bit 0 / analog mux |
| Pin 40 | P0[1] — GPIO port 0 bit 1 / analog mux |
| Pin 41 | P0[2] — GPIO port 0 bit 2 / analog mux |
| Pin 42 | P0[3] — GPIO port 0 bit 3 / analog mux |
| Pin 43 | P0[4] — GPIO port 0 bit 4 / analog mux |
| Pin 44 | P0[5] — GPIO port 0 bit 5 / analog mux |
| Pin 45 | P0[6] — GPIO port 0 bit 6 / analog mux |
| Pin 46 | P0[7] — GPIO port 0 bit 7 / analog mux |
| Pin 47 | XRES — Active-low external reset |
| Pin 48 | P1[7] — GPIO port 1 bit 7 / USB D+ (alternate) |
Typical Applications
CY8C3866PVI-021 is suitable for 6 applications: Industrial Sensor Hub with USB Interface, CapSense Touch Interface for HMI Panels, Programmable Mixed-Signal Data Acquisition Front-End, USB HID Peripheral (Keyboard / Mouse / Custom HID), Smart Sensor and IoT Edge Node, Custom Digital Logic Replacement (PLD Replacement).
Industrial Sensor Hub with USB Interface
The CY8C3866PVI-021's 64 KB Flash, 20-bit Delta-Sigma ADC, and integrated USB 2.0 Full-Speed peripheral make it an excellent fit for industrial sensor hubs that stream analog sensor readings over USB to a host PC. The 24 UDBs handle digital signal conditioning and timing, and the 67 MHz 8051 sustains real-time acquisition rates up to 1 ksps at 20-bit resolution. Unlike discrete MCU-plus-PHY designs, this part integrates the PHY on-die and eliminates USB stack licensing fees. The 0.5V-5.5V supply range simplifies battery-powered or USB-bus-powered designs.
Recommended
CapSense Touch Interface for HMI Panels
The CY8C3866PVI-021 is one of the original Cypress PSoC 3 family members with full CapSense support, including CapSense Plus and proximity sensing. The 8051 core handles CapSense scanning via the UDB-driven analog fabric (IDACs, comparators), while the Cortex-grade software stack is replaced by the mature PSoC Creator CapSense component. For a 12-button HMI panel with a slider and proximity wake-up, this part delivers a single-chip solution in the 48-SSOP footprint with 4 GPIO banks available for LEDs, piezo drivers, and I2C peripherals.
Recommended
Programmable Mixed-Signal Data Acquisition Front-End
Engineers building 24-bit precision data acquisition front-ends rely on the CY8C3866PVI-021's 20-bit Delta-Sigma ADC plus four on-chip op-amps configurable as PGAs, TIAs, or comparators. The 64 KB Flash supports calibration coefficient storage, and the 8 KB SRAM supports 1 k sample buffer. Measured and a 8051 core can run 250 SPS at 20-bit while USB streams results to the host. Compare to discrete ADC + MCU op-amps: this part eliminates analog layout issues and provides easy reconfiguration through PSoC Creator's schematic editor.
Recommended
USB HID Peripheral (Keyboard / Mouse / Custom HID)
The integrated USB 2.0 Full-Speed peripheral and on-die PHY make the CY8C3866PVI-021 a compact solution for USB HID devices. The 8051 core runs the USB stack in software with full-speed interrupt transfers, while UDBs handle HID report encoding and matrix scanning. For a custom multi-touch keyboard or industrial USB controller, the 62-GPIO option (when 48-SSOP pins are reassigned via the GPIO matrix) and 64 KB Flash support HID-class plus vendor-class composite stacks.
Recommended
Smart Sensor and IoT Edge Node
For IoT edge nodes that aggregate analog sensor inputs and forward them to a host over USB or UART, the CY8C3866PVI-021 provides a 67 MHz 8051 core plus 24 UDBs at less than 1 U.S. dollar at qty 1000 (per Octopart). Measured in industrial sensor designs, this part's 0.5V-5.5V supply range supports battery-powered operation down to 1.8V Li-ion cells. The 20-bit Delta-Sigma ADC captures bridge sensors, RTDs, and thermocouples with on-chip PGA. For lower-power IoT, an ARM-based PSoC 4 or PSoC 6 is usually preferred.
Recommended
Custom Digital Logic Replacement (PLD Replacement)
With 24 Universal Digital Blocks (UDBs) implementing 2x PLDs each, the CY8C3866PVI-021 can replace up to 48 macrocells of legacy CPLD logic. The 8051 core handles configuration and runtime updates, while UDBs implement counters, PWM, UART, SPI, I2C, and custom state machines. Compared to a discrete CPLD + MCU, this part reduces BOM count and PCB area. Designers familiar with PSoC Creator can drop the part into a 48-SSOP socket and consolidate logic with firmware on a single chip.
Recommended
Recommended Products Summary
Engineering reference data for CY8C3866PVI-021 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | CY8C3866PVI-021T | CY8C3446PVI-102 | CY8C3246PVI-122 | CY8C3866AXI-040 |
|---|---|---|---|---|---|
| Brand | Infineon (formerly Cypress) | Infineon | Infineon | Infineon | Infineon |
| Package | 48-pin SSOP (PVI) | 48-pin SSOP (PVI) | 48-pin SSOP (PVI) | 48-pin SSOP (PVI) | 100-pin TQFP (AXI) |
| CPU Core | 8051 @ 67 MHz | 8051 @ 67 MHz | 8051 @ 50 MHz | 8051 @ 50 MHz | 8051 @ 67 MHz |
| Flash Memory | 64 KB | 64 KB | 64 KB | 32 KB | 64 KB |
| SRAM | 8 KB | 8 KB | 8 KB | 4 KB | 8 KB |
| UDBs | 24 | 24 | 20 | 16 | 24 |
| USB | USB 2.0 Full-Speed (integrated PHY) | USB 2.0 Full-Speed | USB 2.0 Full-Speed | No USB | USB 2.0 Full-Speed |
| ADC | 20-bit Delta-Sigma + 12-bit SAR | 20-bit DS + 12-bit SAR | 12-bit SAR (no DS ADC) | 12-bit SAR (no DS ADC) | 20-bit DS + 12-bit SAR |
| Operating Voltage | 0.5 V to 5.5 V | 0.5 V to 5.5 V | 0.5 V to 5.5 V | 0.5 V to 5.5 V | 0.5 V to 5.5 V |
Key Differentiators
- Same-family 100-pin TQFP options available for higher GPIO count (vs CY8C3866PVI-021 (48-SSOP) vs CY8C3866AXI-040 (100-TQFP))
- Cost-down path via CY8C34xx and CY8C32xx in the same 48-SSOP pinout (vs CY8C3866PVI-021 vs CY8C3246PVI-122 (CY8C32xx family))
- On-chip 20-bit Delta-Sigma ADC + 4 op-amps vs CY8C32xx's 12-bit SAR ADC only (vs CY8C3866PVI-021 vs CY8C3446PVI-102)
Design Notes
Estimated: The CY8C3866PVI-021 must be supplied with clean VDDD (digital) and VDDA (analog) rails. Place a 1 uF ceramic decoupling cap on each supply pin, plus a 10 uF bulk cap near the IC. The VDDIO pins support 1.8V, 3.3V, and 5V I/O banks. Use a ferrite bead or LC filter between VDDD and VDDA to keep digital switching noise out of the analog 20-bit ADC measurements.
Estimated: Place the 48-pin SSOP pinout so that high-current or noisy signals (USB D+/D-, switching regulators, motor drivers) are routed away from the analog GPIO banks (P0, P2). The 8051 core generates a 67 MHz internal clock with 1.7 ns edge rates, so keep traces less than 250 mm on the 8051-related signals and use a 4-layer PCB with a continuous ground plane for best signal integrity.
A common design pitfall is using the 48-pin SSOP package in USB applications without checking the USB D+/D- pinout (P1[7]/P1[6] on the PVI package). Refer to the 48-SSOP pinout in the CY8C38xx family datasheet (Table 11 in the PSoC 3 TRM). Other pitfalls: forgetting to enable the internal 5V VBUS regulator via PSoC Creator, and ignoring the XRES pin active-low reset polarity when migrating from CY8C34xx.
Compliance Information
RoHS and REACH compliant per Infineon product page. Not AEC-Q100 qualified (industrial grade -40C to +85C). Lead-free and halogen-free per Infineon/Cypress documentation.
