Part A
ADUC812BS
Équipement de simulation
- Lifecycle
- Active
- Stock
- 2004 PCS
- Series
- Embarqué - microcontrôleur
Replacement verdict
Compatible functional replacement candidate
The ADUC848BSZ62-3 and ADUC812BS are both MicroConverter 12-bit ADC MCUs from Analog Devices, but they differ in core architecture, memory density, supply voltage, and package footprint. The ADUC848BSZ62-3 offers a larger 62 kB flash program memory and an 8051-compatible core operating at 3 V, while the ADUC812BS shares the 8051 core but provides 8 kB flash and is specified for 5 V operation in a different package. Because the supply voltage, memory size, and package are not interchangeable, the ADUC848BSZ62-3 is not a direct drop-in replacement for the ADUC812BS; a board-level redesign and firmware revalidation are required before substitution.
Core Architecture
Not compatible
Program Memory Size
Not compatible
Supply Voltage
Not compatible
Package Type
Not compatible
Parts at a glance
Part B
ADUC848BSZ62-3
Analog Equipment GmbH.
- Lifecycle
- Active
- Stock
- 5759 PCS
- Package
- QFP-52
- Series
- Embarqué - microcontrôleur
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADUC848BSZ62-3 | ADUC812BS | Why it matters |
|---|---|---|---|
| Core / Architecture | 8052-compatible 8-bit MCU core | 8052-compatible 8-bit MCU core | Both use the same 8052 instruction set, so firmware source code is largely portable between the two parts. |
| Program Memory (Flash) | 62 kB on-chip Flash | 8 kB on-chip Flash | The much larger Flash on the ADUC848 allows significantly larger application code; the ADUC812 may not fit the same firmware. |
| On-chip RAM | 2 kB + 4 kB (XRAM) | 256 B + 640 B (XRAM) | More RAM supports larger data buffers and stacks; the ADUC812 has far less working memory for the same application. |
| ADC Resolution / Channels | 16-bit sigma-delta ADC, up to 10 channels | 12-bit SAR ADC, 8 channels | The 16-bit sigma-delta ADC provides much higher precision for low-level sensor signals, while the 12-bit SAR is faster but less precise. |
| DAC | 12-bit voltage-output DAC | 12-bit voltage-output DAC | Both include a 12-bit DAC, so analog output capability is comparable between the two devices. |
| Supply Voltage | 3 V (2.7 V to 3.6 V) | 5 V (4.5 V to 5.5 V) | Different supply rails mean the parts are not pin/board compatible without level shifting and power supply redesign. |
| Max CPU Clock | 12.58 MHz | 12 MHz | Similar clock speeds give comparable instruction throughput, though timing-sensitive code may need revalidation. |
| UART / Serial Ports | 1 UART, plus SPI and I2C | 1 UART, plus SPI and I2C | Both offer the same serial communication peripherals, so interface requirements are met by either part. |
| Package | 52-lead MQFP | 52-lead MQFP | Identical package footprint allows the same PCB land pattern, though pin functions and supply differ. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Both are rated for industrial temperature ranges, so environmental suitability is equivalent. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADUC812BS | ADUC848BSZ62-3 |
|---|---|---|
| Brand | Analog Devices | - |
| Product Type | 8-bit Microcontrollers - MCU | - |
| Subcategory | Microcontrollers - MCU | - |
| Minimum Operating Temperature | - 40 C | - |
| Maximum Operating Temperature | + 85 C | - |
| Core | 8052 | - |
| Program Memory Size | 8 kB | 62KB (62K x 8) |
| Data RAM Size | 256 B | - |
| ADC Resolution | 12 bit | - |
| Number of I/O | 34 I/O | 34 |
| Supply Voltage - Min | 2.7 V, 4.5 V | - |
| Supply Voltage - Max | 3.3 V, 5.5 V | - |
| Mounting Type | SMD/SMT | Surface Mount |
| Data Bus Width | 8 bit | - |
| Series | ADUC812 | MicroConverter® ADuC8xx |
| Interface Type | SPI, UART | - |
| Number of ADC Channels | 8 Channel | - |
| Number of Timers / Counters | 3 Timer | - |
| Program Memory Type | Flash | FLASH |
| Data RAM Type | SRAM | - |
| Product | MCUs | - |
| DAC Resolution | 12 bit | - |
| Watchdog Timers | Watchdog Timer | - |
| Processor Series | ADUC812 | - |
| Development Kit | EVAL-ADuC812QSZ | - |
| Part Status | - | Active |
| Core Processor | - | 8052 |
| Core Size | - | 8-Bit |
| Speed | - | 12.58MHz |
| Connectivity | - | I²C, SPI, UART/USART |
| Peripherals | - | POR, PSM, PWM, Temp Sensor, WDT |
| EEPROM Size | - | 4K x 8 |
| RAM Size | - | 2.25K x 8 |
| Voltage - Supply (Vcc/Vdd) | - | 2.7V ~ 3.6V |
| Data Converters | - | A/D 10x16b; D/A 1x12b, 2x16b |
| Oscillator Type | - | Internal |
| Operating Temperature | - | -40°C ~ 125°C (TA) |
Frequently asked questions
What are the key differences between the ADUC848BSZ62-3 and the ADUC812BS?
The ADUC848BSZ62-3 is a MicroConverter with a 62 kB Flash program memory, 4 kB Flash data memory, and 2 kB SRAM, operating from a 3 V supply. The ADUC812BS is a MicroConverter with 8 kB Flash program memory and 640 bytes Flash data memory, operating from a 3 V or 5 V supply. The ADUC848BSZ62-3 offers significantly larger on-chip memory and a higher-resolution ADC (24-bit primary ADC) compared to the ADUC812BS (12-bit ADC).
Are the ADUC848BSZ62-3 and ADUC812BS pin-compatible?
No. The ADUC848BSZ62-3 is supplied in a 52-lead MQFP package, while the ADUC812BS is supplied in a 52-lead MQFP package as well, but the pin functions and internal peripheral mapping differ between the two devices. A direct drop-in replacement is not supported; the PCB layout and firmware must be validated against the respective datasheets.
What is the ADC resolution of each device?
The ADUC848BSZ62-3 integrates a 24-bit sigma-delta primary ADC plus a 12-bit auxiliary ADC. The ADUC812BS integrates a 12-bit successive-approximation ADC with 8 channels. The ADUC848BSZ62-3 is therefore suited to higher-resolution precision measurement applications.
What are the operating supply voltage ranges for these parts?
The ADUC848BSZ62-3 operates from a 3 V supply (2.7 V to 3.6 V). The ADUC812BS operates from either a 3 V supply (2.7 V to 3.6 V) or a 5 V supply (4.5 V to 5.5 V). Designs migrating between the two must confirm the supply rail matches the target device's specified range.
How do the on-chip Flash memory sizes compare?
The ADUC848BSZ62-3 provides 62 kB of Flash program memory, 4 kB of Flash data memory, and 2 kB of SRAM. The ADUC812BS provides 8 kB of Flash program memory and 640 bytes of Flash data memory, with 256 bytes of SRAM. The ADUC848BSZ62-3 supports substantially larger firmware and data-logging requirements.
Do both devices include an on-chip UART and serial interfaces?
Yes. Both the ADUC848BSZ62-3 and the ADUC812BS integrate a UART serial port, an SPI interface, and an I2C-compatible interface. The ADUC848BSZ62-3 additionally includes a dual-channel 16-bit PWM DAC and a wake-up timer, which the ADUC812BS does not provide.
What are the operating temperature ranges for these devices?
Both the ADUC848BSZ62-3 and the ADUC812BS are specified for the industrial temperature range of −40 °C to +85 °C. This must be confirmed against the specific orderable part number and manufacturer datasheet before use in a design.