# CC2541F256RHAR

**Texas Instruments** · RF Transceiver ICs · WQFN-40-EP(6x6)

CC2541F256RHAR from Texas Instruments, in a WQFN-40-EP(6x6). Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | GND | power_in | Ground connection for digital circuit; must be connected to PCB ground plane and solid ground pour. |
| 2 | SCL | bidirectional | I2C serial clock input or general-purpose I/O pin; leave floating if not used, disable internal pull-up if grounded. |
| 3 | SDA | bidirectional | I2C serial data input/output or general-purpose I/O pin; leave floating if not used, disable internal pull-up if grounded. |
| 4 | NC | unconnected | Not connected; reserved pin that must not be connected to external circuitry. |
| 5 | P1_5 | bidirectional | General-purpose I/O port 1.5 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 6 | P1_4 | bidirectional | General-purpose I/O port 1.4 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 7 | P1_3 | bidirectional | General-purpose I/O port 1.3 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 8 | P1_2 | bidirectional | General-purpose I/O port 1.2 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 9 | P1_1 | bidirectional | General-purpose I/O port 1.1 pin with 20-mA drive capability for LED control or high-current output. |
| 10 | DVDD2 | power_in | 2-V to 3.6-V digital power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 11 | P1_0 | bidirectional | General-purpose I/O port 1.0 pin with 20-mA drive capability for LED control or high-current output. |
| 12 | P0_7 | bidirectional | General-purpose I/O port 0.7 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 13 | P0_6 | bidirectional | General-purpose I/O port 0.6 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 14 | P0_5 | bidirectional | General-purpose I/O port 0.5 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 15 | P0_4 | bidirectional | General-purpose I/O port 0.4 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 16 | P0_3 | bidirectional | General-purpose I/O port 0.3 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 17 | P0_2 | bidirectional | General-purpose I/O port 0.2 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 18 | P0_1 | bidirectional | General-purpose I/O port 0.1 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 19 | P0_0 | bidirectional | General-purpose I/O port 0.0 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 20 | RESET_N | input | Active-low asynchronous reset input; minimum pulse width 1 µs; must stay high during normal operation. |
| 21 | AVDD5 | power_in | 2-V to 3.6-V analog power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 22 | XOSC_Q1 | bidirectional | 32-MHz crystal oscillator pin 1 or external clock input; connect to primary oscillator node or external clock source. |
| 23 | XOSC_Q2 | bidirectional | 32-MHz crystal oscillator pin 2; connect to secondary oscillator node of 32-MHz crystal. |
| 24 | AVDD3 | power_in | 2-V to 3.6-V analog power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 25 | RF_P | bidirectional | Positive differential RF signal input to low-noise amplifier during RX; positive output from power amplifier during TX. |
| 26 | RF_N | bidirectional | Negative differential RF signal input to low-noise amplifier during RX; negative output from power amplifier during TX. |
| 27 | AVDD2 | power_in | 2-V to 3.6-V analog power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 28 | AVDD1 | power_in | 2-V to 3.6-V analog power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 29 | AVDD4 | power_in | 2-V to 3.6-V analog power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 30 | RBIAS | input | Analog input for external precision bias resistor (56 kΩ ±1% recommended); sets internal reference current for on-chip biasing network. |
| 31 | AVDD6 | power_in | 2-V to 3.6-V analog power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 32 | P2_4/OSC32K_Q1 | bidirectional | General-purpose I/O port 2.4 or 32.768-kHz crystal oscillator input pin 1; function selected by firmware configuration. |
| 33 | P2_3/OSC32K_Q2 | bidirectional | General-purpose I/O port 2.3 or 32.768-kHz crystal oscillator input pin 2; function selected by firmware configuration. |
| 34 | P2_2 | bidirectional | General-purpose I/O port 2.2 or debug clock input; dual function for in-circuit debugging. |
| 35 | P2_1 | bidirectional | General-purpose I/O port 2.1 or debug data input/output; dual function for in-circuit debugging. |
| 36 | P2_0 | bidirectional | General-purpose I/O port 2.0 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 37 | P1_7 | bidirectional | General-purpose I/O port 1.7 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 38 | P1_6 | bidirectional | General-purpose I/O port 1.6 pin; configurable as input or output with programmable pull-up/pull-down resistor. |
| 39 | DVDD1 | power_in | 2-V to 3.6-V digital power supply input pin; requires 100-nF decoupling capacitor to ground. |
| 40 | DCOUPL | power_out | 1.8-V output from on-chip digital voltage regulator; requires 1-µF decoupling capacitor; do not use to supply external circuits. |
| 41 | GND (Exposed Pad) | power_in | Thermal and mechanical ground connection from exposed die attach pad; must be soldered to solid PCB ground plane for proper heat dissipation. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | WQFN-40-EP(6x6) |
| Category | RF And Wireless |
| Pins | 41 |

## CAD (KiCad official)

- Symbol: `CC2541F256RHAR`
- Footprint: `Package_DFN_QFN:QFN-40-1EP_6x6mm_P0.5mm_EP4.6x4.6mm`
- 3D model: WQFN-40-EP(6x6) (KiCad packages3D, STEP)
- 3D model files: `cc2541f256rhar-etched.step` / `cc2541f256rhar-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `cc2541f256rhar.step` / `cc2541f256rhar.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/cc2541) (37 pp, sha256 `6a99abaeb2964fdb`, retrieved 2026-09-21, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.2`, primary `claude-haiku-4-5-20251001` (text), consensus `claude-sonnet-4-6` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/cc2541f256rhar-datasheet.pdf)