CC1021RSS Equivalent & Substitute Parts

Part Overview

The CC1021RSS is a surface-mount RF transceiver IC designed for General ISM band applications below 1GHz, operating across 402MHz–470MHz and 804MHz–960MHz frequency ranges. This device integrates TxRx-only functionality with FSK, GFSK, and OOK modulation support, delivering 10dBm output power and -109dBm sensitivity. The CC1021RSS is classified as obsolete, making identification of functionally compatible alternatives essential for ongoing system support and new design implementations.

Substiute Parts

CC1021RSS

Texas InstrumentsIn Stock: 810CC1021RSS Datasheet

Current PartRFQ

CC1121RHBT

Texas InstrumentsIn Stock: 3190CC1121RHBT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The CC1121RHBT serves as a manufacturer-recommended substitute for the obsolete CC1021RSS. Substitution eligibility is determined by the following criteria:

Frequency Compatibility: The CC1121RHBT operates across 164MHz–192MHz, 274MHz–320MHz, 410MHz–480MHz, and 820MHz–960MHz. The overlapping bands (410MHz–480MHz and 820MHz–960MHz) align with the CC1021RSS operating ranges, enabling frequency-compatible applications.

Modulation Support: The CC1121RHBT supports 2FSK, 2GFSK, 4FSK, 4GFSK, MSK, and OOK modulation. This includes all modulation types used by the CC1021RSS (FSK, GFSK, OOK), ensuring protocol compatibility for existing designs.

Interface Compatibility: Both devices feature SPI serial interface. The CC1021RSS includes UART and 1 GPIO; the CC1121RHBT provides SPI with 4 GPIO pins, offering expanded I/O capability.

Package Compatibility: Both devices use 32-pin VQFN packages with exposed pads. The CC1021RSS uses 7x7mm footprint; the CC1121RHBT uses 5x5mm footprint. Physical PCB layout modification is required.

Voltage Supply Range: The CC1121RHBT operates at 2V–3.6V, which encompasses the CC1021RSS range of 2.3V–3.6V, ensuring power supply compatibility.

Functional Enhancement: The CC1121RHBT integrates an embedded MCU with 4kB ROM and 256B RAM, providing additional processing capability beyond the TxRx-only architecture of the CC1021RSS.

Parameter Comparison

Engineering Selection Recommendations

For Obsolescence Mitigation: The CC1021RSS is classified as obsolete. The CC1121RHBT is active and available in production quantities (3080 pcs in stock), making it the appropriate choice for new designs and long-term system support.

Compliance Alignment: Both devices are ROHS3 compliant and REACH unaffected, maintaining regulatory compliance across substitution.

Frequency Band Verification: Applications operating within the overlapping frequency bands (410MHz–480MHz and 820MHz–960MHz) are directly compatible. Applications requiring 402MHz–409MHz or 470MHz–479MHz operation require frequency band reassessment, as the CC1121RHBT minimum frequency is 410MHz.

Package Footprint Consideration: The CC1121RHBT uses a smaller 5x5mm package compared to the CC1021RSS 7x7mm package. PCB layout redesign is necessary; however, the reduced footprint provides space optimization benefits.

Moisture Sensitivity: The CC1121RHBT has MSL rating 3 (168-hour floor life), compared to CC1021RSS MSL rating 1 (unlimited). Storage and handling procedures must account for this increased moisture sensitivity.

Frequently Asked Questions (FAQ)

Q: Can the CC1121RHBT directly replace the CC1021RSS without firmware changes?

A: Frequency band compatibility must be verified first. Both devices support overlapping ISM bands and common modulation types (FSK, GFSK, OOK). However, the CC1121RHBT integrates an embedded MCU, requiring firmware adaptation if the original design relied on external microcontroller control. SPI interface is common to both; UART functionality in the CC1021RSS must be reimplemented through the CC1121RHBT MCU if required.

Q: What are the frequency band differences between these devices?

A: The CC1021RSS operates at 402MHz–470MHz and 804MHz–960MHz. The CC1121RHBT operates at 164MHz–192MHz, 274MHz–320MHz, 410MHz–480MHz, and 820MHz–960MHz. Overlapping bands are 410MHz–480MHz and 820MHz–960MHz. Applications requiring 402MHz–409MHz operation cannot use the CC1121RHBT.

Q: Does the smaller package size affect electrical performance?

A: Package size reduction (7x7mm to 5x5mm) does not alter electrical specifications. PCB layout must accommodate the smaller footprint; trace routing and component placement require redesign.

Q: What is the impact of increased transmit current in the CC1121RHBT?

A: The CC1121RHBT transmit current range (26mA–54mA) is higher than the CC1021RSS (12.3mA–27.1mA). Power supply design must provide adequate current capacity. Battery-powered applications require power budget reassessment.

Q: Is the CC1121RHBT suitable for applications requiring UART communication?

A: The CC1021RSS provides dedicated UART interface. The CC1121RHBT does not include UART; serial communication must be implemented through the embedded MCU using SPI or GPIO-based protocols. Firmware development is required.

Q: How does the embedded MCU in the CC1121RHBT affect system architecture?

A: The CC1021RSS is TxRx-only, requiring external microcontroller for system control. The CC1121RHBT integrates a microcontroller with 4kB ROM and 256B RAM, enabling single-chip solutions. System architecture can be simplified, but firmware must be developed for the integrated MCU.

Q: What are the storage requirements for the CC1121RHBT?

A: The CC1121RHBT has MSL rating 3 (168-hour floor life). Components must be stored in controlled humidity environments and used within 168 hours of package opening. The CC1021RSS (MSL 1) has unlimited floor life, requiring no time-based storage restrictions.