PRODUCT SPECIFICATION

Nordic Semiconductor ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone +4772898900 - Fax +4772898989
Revision: 2.1

Page 1 of 32

March 2006

Single chip 2.4 GHz Transmitter

FEATURES

APPLICATIONS

True single chip GFSK transmitter in a
small 16-pin package (QFN16 4x4)

· Wireless mouse, keyboard, joystick

Keyless entry

Adjustable output power up to 0dBm

Wireless data communication

Data rate 0 to 1Mbps

Alarm and security systems

Low Bill of Material

Home Automation

· Multi Channel operation

· 128 channels

Support frequency hopping

Channel switching time <200

µs.

Remote control

Surveillance

Automotive

Telemetry

Power supply range: 1.9 to 3.6 V

CRC computation

Intelligent sports equipment

Industrial sensors

ShockBurstTM mode for ultra-low power
operation

Toys

Low supply current, typical 10mA peak

@ -5dBm output power

· 100% RF tested

World wide use

GENERAL DESCRIPTION

nRF2402 is a single-chip radio transmitter for the world wide 2.4 - 2.5 GHz ISM
band. The transmitter consists of a fully integrated frequency synthesizer, a power
amplifier, a crystal oscillator and a modulator. Output power and frequency channel is
easily programmable by use of the 3-wire interface. Current consumption is very low,
only 10 mA at an output power of -5dBm. Built-in ShockBurstTM and Power Down
modes make power saving easily realizable.

QUICK REFERENCE DATA

Parameter Value

Unit

Minimum supply voltage

1.9

Maximum output power

dBm

Maximum GFSK data rate

1000

kbps

Supply current GFSK transmitter @ -5dBm output power

Supply current in Power Down mode

200

Table 1 nRF2402 quick reference data

Type Number

Description

Version

NRF2402G

16 pin QFN 4x4, RoHS & SS-00259 compliant

Table 2 nRF2402 ordering information

nRF2402

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 2 of 32

March 2006

BLOCK DIAGRAM

VDD (1

XC1 (7)

VS
S (
5

)

IREF (14)

VDD_PA (12)

VSS_PA (9)

Frequency

Synthesiser

DD (8

)

XC2 (6)

ANT1 (10)

ANT2 (11)

22k

FIFO

CRC
Code

ShockBurst

DIN (4)

CLK (3)

CS (2)

3-wire

Interface

PWR_UP (16)

CE (1)

3-wire

Programming

Interface

GFSK

Filter

S (15)

Figure 1 nRF2402 with external components.

PIN FUNCTIONS

Pin Name

Pin function

Description

Input

Chip Enable Activates TX mode

Input

Chip Select Activates Configuration Mode

CLK

Input

Clock Input TX Data and 3-wire Interface

DIN

Input

TX Data Input / Configuration Data Input

VSS

Power

Ground (0V)

XC2

Output

Crystal pin 2

XC1

Input

Crystal pin 1

VDD

Power

Power Supply (1.9-3.6V)

9 VSS_PA

Power

Ground

(0V)

ANT1

Power/RF

Antenna output 1

ANT2

Power/RF

Antenna output 2

VDD_PA

Power Output

Power Supply (+1.8V) output to internal Power Amplifier

VDD

Power

Power Supply (1.9-3.6V)

14 IREF

Input

Reference

current

15 VSS

Power

Ground

(0V)

16 PWR_UP

Input

Power

Table 3 nRF2402 pin functions

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 4 of 32

March 2006

ELECTRICAL SPECIFICATIONS

Conditions: VDD = +3V, VSS = 0V, T

= - 40ºC to + 85ºC

Symbol Parameter

(condition)

Notes

Min.

Typ.

Max. Units

Operating conditions

VDD

Supply voltage

1.9

3.0

3.6

TEMP

Operating Temperature

-40

+27

+85

ºC

Digital input pin

HIGH level input voltage

0.7·VDD VDD

LOW level input voltage

Vss

0.3·VDD V

Digital output pin

HIGH level output voltage (I

=-0.5mA)

VDD-

0.3

VDD

LOW level output voltage (I

=0.5mA) Vss

0.3

General RF conditions

Operating

frequency

2400

2527 MHz

XTAL

Crystal frequency

MHz

Frequency deviation

±156

kHz

GFSK

GFSK data rate ShockBurstTM

1000

kbps

GFSK

GFSK data rate Direct Mode

250

1000

kbps

CHANNEL

Channel

spacing

MHz

Transmitter operation

Maximum

Output

Power

dBm

RFC

RF Power Control Range

RFCR

RF Power Range Control Resolution

±3

20dB Bandwidth for Modulated Carrier

1000

kHz

RF2

Adjacent Channel Transmit Power 2MHz

-20

dBc

RF3

Adjacent Channel Transmit Power 3MHz

-40

dBc

VDD

Supply current @ 0dBm output power

11.5

VDD

Supply current @ -5dBm output power

10.0

VDD

Supply current @ -10dBm output power

8.5

VDD

Supply current @ -20dBm output power

7.0

VDD

Average Supply current @ -5dBm output
power, ShockBurstTM

6) 500

µA

VDD

Supply current in stand-by mode

µA

VDD

Supply current in power down

200

NOTES:
1) Usable band is determined by local regulations
2) The crystal frequency may be chosen from 5 different values (4, 8, 12, 16, and 20MHz) which are specified in

the configuration word, see Table 8. 16MHz is required

for 1Mbps operation.

3) Data rate must be either 250kbps or 1000kbps.
4) Antenna load impedance =

100

+j175

5) Antenna load impedance =

100

+j175.

Effective data rate 250kbps or 1Mbps.

6) Antenna load impedance =

100

+j175.

Effective data rate 10kbps.

Table 4 nRF2402 electrical specifications

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 6 of 32

March 2006

Package Type

D/E

D2/E2

SAW

QFN16

(4x4 mm)

Min

Typ.
Max

0.80
0.85
0.90

0.00
0.02
0.05

0.20

REF.

0.20

min

4.0

BSC

0.65

BSC

2.00
2.10
2.20

0.45
0.50
0.55

0.25
0.30
0.35

Figure 3 nRF2402 Package outline, dimensions in mm.

BSC: Basic Spacing between Centers, ref. JEDEC standard 95, page 4.17-11/A

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 7 of 32

March 2006

Package marking:

Abbreviations:
B

Build Code, i.e. unique code for production sites,

package type and test platform

"X" grade, i.e. Engineering Samples (optional)

2 digit Year number

2 digit Week number

2 letter wafer lot number code

ABSOLUTE MAXIMUM RATINGS

Supply voltages
VDD ............................- 0.3V to + 3.6V
VSS .................................................. 0V

Input voltage
V

....................... - 0.3V to VDD + 0.3V

Output voltage
V

...................... - 0.3V to VDD + 0.3V

Total Power Dissipation
P

=85

°C) ............................. 35mW

Temperatures
Operating Temperature.... - 40

°C to + 85°C

Storage Temperature...... - 40

°C to + 125°C

Moisture Sensitivity Level
MSL3@260ºC, three times reflow

Note: Stress exceeding one or more of the limiting values may cause permanent
damage to the device.

ATTENTION!

Electrostatic Sensitive Device
Observe Precaution for handling.

n R F

B X

2 4 0 2 G

Y Y W W L L

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 8 of 32

March 2006

GLOSSARY OF TERMS

Term Description

CLK Clock
CRC

Cyclic Redundancy Check

CS Chip

Select

CE Chip

Enable

GFSK

Gaussian Frequency Shift Keying

ISM Industrial-Scientific-Medical
MCU

Micro Controller Unit

OD Overdrive
PWR_DWN Power

Down

PWR_UP Power

RX Receive
ST_BY Standby
TX Transmit

Table 5 Glossary

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 9 of 32

March 2006

MODES OF OPERATION

Overview of Operational Modes

The nRF2402 can be set in the following main modes depending on three control
pins:

Mode

PWR_UP CE

Active 1

Configuration 1 0 1
Stand By

Power Down

Table 6 Overview of Operational Modes of nRF2402.

Active Modes

The nRF2402 has two transmit modes:

· ShockBurstTM

· Direct Mode

The device functionality in these modes is determined by the content of a
configuration word. This configuration word is presented in the configuration section.

ShockBurstTM

The ShockBurstTM technology uses on-chip FIFO to clock in data at a low data rate
and transmit at a very high rate thus enabling extreme reduction in power
consumption.
When operating the nRF2402 (in co-operation with nRF2401/nRF24E1) in
ShockBurstTM, you gain access to the high data rates (1 Mbps) offered by the 2.4 GHz
band without the need of a costly, high-speed micro controller (MCU) for data
processing.
By putting all high speed signal processing related to RF protocol on-chip, the
nRF2402 offers the following benefits:

· Highly reduced current consumption

· Lower system cost (facilitates use of less expensive micro controller)

· Greatly reduced risk of `on-air' collisions due to short transmission time

The nRF2402 can be programmed using a simple 3-wire interface where the data rate
is decided by the speed of the micro controller.
By allowing the digital part of the application to run at low speed while maximizing
the data rate on the RF link, the nRF ShockBurstTM mode reduces the average current
consumption in applications considerably.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 10 of 32

March 2006

ShockBurstTM principle

When the nRF2402 is configured in ShockBurstTM, TX operation is conducted in the
following way (10 kbps for this example only).

Figure 4 Clocking in data with MCU and sending with ShockBurst

technology

Time mS

100

120

140

160

180

200

220

240

10mA

periode

10mA periode

Without ShockBurst

, running at speed dictated by 10kbps MCU

10kbps MCU with ShockBurst

Figure 5 Current consumption with and without ShockBurst

technology

nRF2402 ShockBurstTM Transmit:

MCU interface pins: CE, CLK, DIN

1. When the application MCU has data to send, set CE high. This activates

RF2402 on-board data processing.

2. The address of the receiving node (RX address) and payload data is

clocked into the nRF2402. The application protocol or MCU sets the speed
(ex: 10kbps).

3. MCU sets CE low, this activates a nRF2402 ShockBurstTM transmission.
4. nRF2402 ShockBurstTM:

· RF front end is powered up

· RF package is completed (preamble added, CRC calculated)

· Data is transmitted at high speed (250 kbps or 1 Mbps configured

by user).

· nRF2402 returns to stand-by when finished

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 11 of 32

March 2006

uController

Loading ADDR
and PAYLOAD

data

nRF2402

Calculating CRC

ADDR

PAYLOAD

ADDR

PAYLOAD

CRC

Data content of registers:

nRF2402 in

ShockBurst

TX (CE=hi)?

YES

Maximum 256 bits

nRF2402

Adding Preamble

nRF2402

Sending

ShockBurst

Package

(250 or 1000kbps)

Pre-

amble

ADDR

PAYLOAD

CRC

Sending

completed?

YES

CE=Low?

YES

Input FIFO not Empty

Figure 6 Flow Chart ShockBurstTM Transmit of nRF2402 with CRC and preamble.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 12 of 32

March 2006

Direct Mode

In direct mode the nRF2402 works like a traditional RF device. The data rate must be
1Mbps ±200ppm, or 250kbps ±200ppm at low data rate setting, for the receiver
(nRF2401A/nRF24E1) to detect the signals.

MCU interface pins: CE, DIN

1. When application MCU has data to send, set CE high
2. The nRF2402 RF front end is now immediately activated, and after 200

µs

settling time, signal on the DIN pin will modulate the carrier directly.

3. All RF protocol parts must hence be implemented in MCU firmware

(preamble, address and CRC).

Configuration Mode

In configuration mode a configuration word of up to 20 bits is downloaded to
nRF2402. This is done through a simple 3-wire interface (CS, CLK and DIN). For
more information on configuration please refer to the nRF2402 device configuration
chapter, page13.

Power Down Mode

Power down mode is used to achieve very low current consumption. Effectively the
chip is disabled with minimal leakage current consumption, typically less than 200nA.
Operating in this mode when not transmitting data significantly increases battery
lifetime.

Stand-By Mode

Stand by mode is used to achieve low current consumption. In this mode only a part
of the crystal oscillator is running (12

µA) to guarantee a short start-up time. Operating

in this mode when not transmitting data increases battery lifetime while keeping start
up delays short.

Pin configuration for the different modes of nRF2402

nRF2402 MODES

INPUT PINS

Pin Name

PWR_UP CE

CLK

DIN

Power down

Stand by

Configuration 1

CLK

CONFIG DATA

TX ShockBurstTM

CLK

TX DATA

TX Direct

1 1 0

Set to 0

TX DATA

Table 7 Pin configuration of nRF2402.

CLK not used in direct mode.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 13 of 32

March 2006

DEVICE CONFIGURATION

All configuration of the nRF2402 is done via a 3-wire interface to a single
configuration register. The configuration word can be up to 20 bits long for
ShockBurstTM use and up to 14 bits long for direct mode.

Configuration for ShockBurstTM operation

The configuration word in ShockBurstTM enables the nRF2402 to handle the RF
protocol (in co-operation with nRF2401A/nRF24E1). Once the protocol is completed
and loaded into nRF2402 only seven bits, also used in direct mode, needs to be
updated during operation.

The configuration bits dedicated to ShockBurstTM is as follows:

· Preamble: Generation of 8 bit preamble in transmitted data.

· CRC: Enables nRF2402 on-chip CRC generation.

NOTE:
The MCU must generate an address and a payload section that fits the configuration
of the nRF2401A/nRF24E1 that is to receive the data.
When using the nRF2402 on-chip CRC feature ensure that CRC is enabled and uses
the same length for both the nRF2402 and the receiving nRF2401A/nRF24E1 devices.

PRE-AMBLE

ADDRESS

PAYLOAD

CRC

Figure 7 Data packet set-up

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 14 of 32

March 2006

Configuration for Direct Mode operation

For direct mode operation only the 14 first bits (bit[13:0]) of the configuring word is
relevant.

Configuration Word overview

Bit

position

Number

of bits

Name Function

PLL Control

Close the PLL for test.

18 1

UNUSED

PREAMBLE

Enable on-chip PREAMBLE generation

PREAMBLE

UNUSED, must be 1

CRC

8 or 16 bit CRC

CRC

Enable on-chip CRC generation

Communication mode (Direct or ShockBurstTM)

RFDR_SB

RF data rate (1Mbps requires 16MHz crystal)

11:9 3

XO_F

Crystal

frequency

8:7 2

RF_PWR

output

power

Gen

e
ral d

e
vi

conf

igura

t
i
o

6:0

RF_CH#

Frequency channel (0 to 127)

Table 8 Table of configuration words.

The configuration word is shifted in MSB first on positive CLK edges. New
configuration is enabled on the negative edge of CS.

NOTE!
On the negative edge of CS, the nRF2402 updates the number of bits actually shifted
in during the last configuration.
Ex:
If the nRF2402 is to be configured for Preamble and CRC in ShockBurstTM, a total of
17 bits must be shifted in during the first configuration after VDD is applied.
Once the wanted "protocol" and modus are set there is no need to update this part of
the configuration during operation. If RF channel is to be changed, only the RF_CH#
bits need to be updated.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 15 of 32

March 2006

Configuration Word Detailed Description

The following describes the function of the 32 bits (bit 31 = MSB) that is used to
configure the nRF2402.
General Device Configuration: bit[13:0]
ShockBurstTM Configuration: bit[17:14]
Test Configuration: bit[19:18]

TEST ShockBurst

D19 D18

D17 D16

D15 D14

PLL

PRE_EN

CRC

0 0

1 1

0 0

Default

RF-Programming

LSB

D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

Burst

XO Frequency

RF Power

Channel selection

0 0 1 1 1 1 0 0 0 0 0 0 1 0

Default

The MSB bit should be loaded first into the configuration register.
Default configuration word: h30F02.

Test configuration

Bit 19:

PLL: For test purposes the PLL may be closed to send a constant carrier

Logic 0: Open loop (normal operation)
Logic 1: Closed loop (test only)

Bit: 18:

Not used, must be set to logic 1

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 16 of 32

March 2006

ShockBurstTM configuration

The section bit[17:14] contains the segments of the configuration register dedicated to
ShockBurstTM operation. After VDD is turned on ShockBurstTM configuration must be
done once, but remains set whilst VDD is present. During operation only the 7 bits for
frequency channel normally need to be changed.

PREAMBLE CRC

17 16

Table 9 Preamble and CRC settings.

Bit 17:

PRE_EN:

Preamble to be generated by nRF2402 in ShockBurstTM.
Logic 0: No generation of Preamble
Logic 1: Preamble generation enabled (default)

Bit: 16:

Not used, must be set to logic 1

Bit 15:

CRC_L:

CRC length to be calculated by nRF2402 in ShockBurstTM.
Logic 0: 8 bit CRC (default)
Logic 1: 16 bit CRC

Bit: 14:

CRC_EN:

Enables on-chip CRC generation (TX)
Logic 0: On-chip CRC generation disabled (default)
Logic 1: On-chip CRC generation

enabled

NOTE:

An 8 bit CRC (compared to 16 bit) will increase the number of payload
bits possible in each ShockBurstTM data packet, but will also reduce the
communication integrity.

General device configuration:
This section of the configuration word handles RF and device related parameters.

Burst OD

XO_F

RF_PWR

13 12

Table 10 RF operational settings.

Bit 13:

Burst:

Logic 0: nRF2402 operates in direct mode (default)

Logic 1: nRF2402 operates in ShockBurstTM mod

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 17 of 32

March 2006

Bit 12:

OD:

Logic 0: 250 kbps data rate

Logic 1: 1 Mbps data rate

NOTE:

1Mbps requires 16MHz crystal.

Bit 11-9:

XO_F:

Selects the nRF2402 crystal frequency to be used:

XO FREQUENCY SELECTION

D11

D10

Crystal Frequency [MHz]

0 0 0

0 0 1

0 1 0

0 1 1

1 0 0

Table 11 Crystal frequency setting.

Bit 8-7:

RF_PWR:

Sets nRF2402 RF output power:

RF OUTPUT POWER

D8 D7 P

[dBm]

0 0

-20

0 1

-10

1 0

-5

1 1

Table 12 RF output power setting.

Conditions: Load impedance = 100+j175

RF channel

RF_CH#

6 5 4 3 2 1 0

Table 13 Frequency channel setting.

Bit 6 0:

RF_CH#:

Sets the frequency channel the nRF2402 transmits in.

The channel frequency is given by:

MHz

Channel

2400

RF_CH #: Frequencies between 2400MHz and 2527MHz may be set.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 18 of 32

March 2006

DATA PACKAGE DESCRIPTION

PRE-AMBLE

ADDRESS

PAYLOAD

CRC

Figure 8 Data Package Diagram

The data packet for both ShockBurstTM mode and direct mode communication is
divided into 4 sections. These are:

PREAMBLE

· The preamble field is a requirement for ShockBurstTM and Direct modes

· Preamble is 8 bits in length and is dependent on the 1

data bit.

PREAMBLE

Data Bit (Address)

01010101 0
10101010 1

· Preamble is automatically added to the data packet and thereby gives

extra space for payload in ShockBurstTM. Preamble must be added by
MCU in Direct mode

ADDRESS

· The address field is required in ShockBurstTM mode.

· 8 to 40 bits length.

· Address automatically removed from received packet in ShockBurstTM

mode. In Direct mode MCU must handle address.

PAYLOAD

· The data to be transmitted

· In ShockBurstTM mode payload size is 256 bits minus the following:

(Address: 8 to 40 bits. + CRC 8 or 16 bits).

· In Direct mode the maximum payload size is defined by 1Mbps for 4ms:

4000 bits minus the following: (Preamble: 8 bits. + Address: 0 to 40 bits.
+ CRC: 0, 8 or 16 bits).

CRC

· On chip CRC calculation is an option in ShockBurstTM mode,

and is not used in Direct mode.

· 8 or 16 bits length

Table 14 Data package

Suggestions for the use of addresses in ShockBurstTM: In general more bits in the address gives less

false detection, which in the end may give lower data packet loss.
· The address made by (5, 4, 3, or 2) equal bytes are not recommended because it in general will make the

packet-error-rate increase.

· Addresses where the level shift only one time (i.e. 000FFFFFFF) could often be detected in noise that may

give a false detection, which again may give raised packet-error-rate.

Direct mode will be dependent on the software used in the MCU, but it is recommended to have the
same restrictions on addresses for this mode.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 19 of 32

March 2006

IMPORTANT TIMING DATA

The following timing applies for operation of nRF2402.

nRF2402 Timing Data

nRF2402 timing

Min.

Max.

Name

PWR_DWN

Configuration mode

3ms

Tpd2cfgm

PWR_DWN

Active mode (TX)

3ms

Tpd2a

ST_BY

TX ShockBurstTM

195

µs

Tsby2txSB

ST_BY

TX Direct Mode

202

µs

Tsby2txDM

Minimum delay from CS to data.

µs

Tcs2data

Minimum delay from CE to data.

µs

Tce2data

Delay between edges

50ns

Setup time

500ns

Hold time

500ns

Delay to finish internal GFSK data

1/data rate

Tfd

Minimum input clock high

500ns

Thmin

Time on air, TX Direct mode

4ms

ToaDM

Table 15 Switching times for nRF2402

When the nRF2402 is powered up it must always settle in stand by for 3ms before it can enter
configuration or active mode.

PWR_UP

DIN

Tpd2cfgm

CLK

Figure 9 Timing diagram for power down (or VDD off) to configuration mode

for nRF2402.

PWR_UP

DIN

Tpd2a

CLK

Figure 10 Power down (or VDD off) to active mode

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 20 of 32

March 2006

Note that the configuration word will be lost when VDD is turned off and that the device then
must be configured before going to active mode. If the device is configured one can go
directly from power down to active mode.
Note:

CE and CS may not be high at the same time. Setting one or the other decides whether
configuration or active mode is entered.

Configuration Mode
In configuration mode the transmitters output power, transmit frequency, data rate, CRC, and
preamble is set. The configuring data will be loaded during the Chip Select period (CS="1").
A random number of bits between 1 and 20 may be shifted in to the register to configure the
transmitter, but normally you would at least shift in the seven channel frequency bits. The
new configuration is activated on the negative edge of CS.

When one or more of the bits in the configuration word needs to be changed the following
timing apply.

Configuration Mode Timing

CLK

DIN

PWR_UP

CLK

DIN

MSB

t = 0

Thmin

cs2

data

Figure 11 Timing Diagram of Configuration Mode

If configuration mode is entered from power down, CS can be set high after Tpd2sby as
shown in Figure 9.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 21 of 32

March 2006

ShockBurstTM Mode Timing

CLK

DIN

PWR_UP

CLK

DIN

2dat

ANT1/ANT2

sby2txSB

Toa

t = 0

Hmin

Figure 12 Timing of ShockBurstTM in nRF2402.

The package length and the data rate give the delay Toa (time on air), as shown in the
equation.

)

databits

datarate

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 22 of 32

March 2006

Direct Mode Timing

CLK

DIN

PWR_UP

ANT1/ANT2

sby2txDM

ToaDM

Tfd

t = 0

Figure 13 Timing Diagram of Direct Mode

In direct mode the input data will be sampled by nRF2402 and therefore no clock is needed.
The clock must be stable at low level during transmission due to noise considerations. The
exact delay T

sby2txDM

is given by the equation:

txDM

sby

194

The maximum length of a package (ToaDM) over all voltages and temperatures is 4ms. This
is limited by frequency drift in the transmitter and is independent of data rate and frequency
channel.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 23 of 32

March 2006

PERIPHERAL

RF INFORMATION

Antenna output

The ANT1 and ANT2 output pins provide a balanced RF output to the antenna. The pins
must have a DC path to VDD_PA, either via a RF choke or via the center point in a balanced
antenna. Differential load impedance between the ANT1 and ANT2 pins, 100

+j175, is

recommended for maximum output power. Antennas with lower load impedance (for
example 50

) can be matched to nRF2402 by using a simple matching network.

Antenna matching networks

The recommended 50

matching network is shown in Figure 14. This is a low pass network

improving higher harmonic suppression.

3.3nH

5.6nH

1.0pF

2.2nF

4.7pF

RF output

10nH

4.7pF

nRF2402

ANT1

ANT2

VDD_PA

Figure 14 Low pass antenna matching network

A somewhat simpler matching network is shown in Figure 15.

nRF2402

ANT1

ANT2

VDD_PA

4.7pF

3.6nH

22nH

1.0pF

2.2nF

Cout
1.5pF

RF output

Figure 15 High pass antenna matching network

This network utilizes one component less and uses few inductors, but performance of this
network requires very careful PCB ground plane layout. The value of capacitor C

out

dependent on PCB ground plane layout and parasitics in the layout, and must hence be
matched to a given application layout. The value of C

out

will typically be in the range 1.0pF

1.8pF. C

out

must be tuned while checking that the harmonics output is below frequency

regulatory limits.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 24 of 32

March 2006

Output Power adjustment

Power setting bits of

configuring word

RF output power

DC current

consumption

0 dBm ±3dB

11.5 mA

-5 dBm ±3dB

10.0 mA

-10 dBm ±3dB

8.5 mA

-20 dBm ±3dB

7.0 mA

Conditions: Load impedance = 100+j175

Table 16 RF output power setting for the nRF2402.

Crystal Specification

Tolerance includes initially accuracy and tolerance over temperature and aging.

Frequency C

ESR

0max

Tolerance

4MHz

8pF 16pF

150

7.0pF

±30ppm

8MHz

8pF 16pF

100

7.0pF

±30ppm

12MHz

8pF 16pF

100

7.0pF

±30ppm

16MHz

8pF 16pF

100

7.0pF

±30ppm

20MHz

8pF 16pF

100

7.0pF

±30ppm

Table 17 Crystal specification of the nRF2402

To achieve a crystal oscillator solution with low power consumption and fast start-up time, it
is recommended to specify the crystal with a low value of crystal load capacitance.
Specifying a lower value of crystal parallel equivalent capacitance, Co=1.5pF is also good,
but this can increase the price of the crystal itself. Typically Co=1.5pF at a crystal specified
for Co_max=7.0pF.

The crystal load capacitance, C

, is given by:

PCB

and

where

and C

are SMD capacitors as shown in the application schematics. C

PCB1

and C

PCB2

are

the layout parasitic on the circuit board. C

and C

are the capacitance seen into the XC1 and

XC2 pin respectively; the value is typical 1pF.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 25 of 32

March 2006

Sharing crystal with micro controller.

When using a micro controller to drive the crystal reference input XC1 of the nRF2402
transmitter some rules must be followed.

Crystal parameters:

When the micro controller drives the nRF2402 XC1 input, all crystal load parameters (C

, C

ESR) are set by the micro controller specification. The frequency accuracy (±30 ppm) is still
set by the nRF2402 specification. The nRF2402 will load the crystal circuitry of the micro
controller by XC1 input capacitance (0.5pF) plus PBC routing parasitic.

External reference input amplitude & Current consumption

The reference input should never have signal levels exceeding rail voltages. Exceeding rail
voltage will excite the ESD structure and the radio performance is degraded below
specification. Applying reference sources without DC bias will bring the reference signal
under GND level, and this is not acceptable.

XC1

XO_OUT

Amplitude

controlled

current source

Buffer:

Sine to

full swing

Current starved

inverter:

XOSC core

XC2

Vdd

Vss

Vdd

Vss

ESD

Figure 16 Principle of crystal oscillator

It is hence recommended to use a DC-block before the XC1 pin so that the internal ESD
structures will self biases the XC1 voltage.

The nRF2402 crystal oscillator is amplitude regulated. To achieve low current consumption
and also good signal-to-noise ratio, it is recommended to use an input signal larger than 0.4
V-peak. The needed input swing is independent of the crystal frequency. When using external
crystal reference, XC2 is not used and can be left as an open pin.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 26 of 32

March 2006

Frequency Reference MCU

In direct mode there is a requirement on the accuracy of the data rate. For the receiver to
detect the incoming data and recover the clock, the data rate must be within ±200ppm, given
that the data is "random", i.e. there is a statistical calculation on how often a preamble like
sequence is present in the data. The clock is synchronized for any preamble detection, be it a
dedicated preamble or part of the data stream.

PCB layout and de-coupling guidelines

A well-designed PCB is necessary to achieve good RF performance. Keep in mind that a poor
layout may lead to loss of performance, or even functionality, if due care is not taken. A fully
qualified RF-layout for the nRF2402 and its surrounding components, including matching
networks, can be downloaded from www.nordicsemi.no.

A PCB with a minimum of two layers including a ground plane is recommended for optimum
performance. The nRF2402 DC supply voltage should be de-coupled as close as possible to
the VDD pins with high performance RF capacitors, see Table

. It is preferable to mount a

large surface mount capacitor (e.g. 4.7

µF tantalum) in parallel with the smaller value

capacitors. The nRF2402 supply voltage should be filtered and routed separately from the
supply voltages of any digital circuitry.

Long power supply lines on the PCB should be avoided. All device grounds, VDD
connections and VDD bypass capacitors must be connected as close as possible to the
nRF2402 IC. The VSS pins should be connected directly to the ground plane. One via hole
should be used for each VSS pin.

Full swing digital data or control signals should not be routed close to the crystal or the
power supply lines.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 27 of 32

March 2006

Reflow information

Figure 17 Soldering reflow profile, GREEN

Ramp rate (RT-150ºC) 1.38 ºC/s
Pre-heat (150-200ºC)

134 s

Dwell @217ºC

50 s

Dwell @245ºC

10 s

Ramp up

1.42 ºC/s

Ramp down

2.59 ºC/s

Peak temperature

257 ºC

Time from RT to PT

320 s

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 28 of 32

March 2006

Application example

nRF2402 with single ended matching network

16MHz

C1
22pF

C2
22pF

R2
22k

C5
1nF

C6
10nF

C3
4.7pF

3.3nH

10nH

C8
1.0pF

C7
1.0pF

VDD

PWR_UP

CLK

DIN

C4
2.2nF

VDD

RF output

4.7pF

5.6nH

VDD_PA

ANT2

ANT1

VSS_PA

CLK

DIN

nRF2402

U1
NRF2402

Figure 18 nRF2402 schematic for RF layouts with single ended 50

antenna

Component Description

Size

Value

Tolerance

Units

Capacitor ceramic, 50V, NPO

0603

±5%

Capacitor ceramic, 50V, NPO

0603

±5%

Capacitor ceramic, 50V, NPO

0603

4.7

±5%

Capacitor ceramic, 50V, X7R

0603

2.2

±10%

Capacitor ceramic, 50V, X7R

0603

1.0

±10%

Capacitor ceramic, 50V, X7R

0603

±10%

R1 Resistor

0603

1.0 ±10% M

R2 Resistor

0603

±1% k

nRF2402 transmitter

QFN16 / 4x4

nRF2402

Crystal, CL = 12pF,
ESR < 100 ohm

LxWxH =

4.0x2.5x0.8

+/-

ppm

MHz

L1 Inductor

0603

3.3

± 5%

L2 Inductor

0603

± 5%

L3 Inductor

0603

5.6

Ceramic capacitor, 50V, NP0

0603

1.0

± 0.1 pF

Ceramic capacitor, 50V, NP0

0603

1.0

± 0.1 pF

Ceramic capacitor, 50V, NP0

0603

4.7

± 0.25 pF

Table 18 Recommended components (BOM) in nRF2402 with antenna matching network

nRF2402 can operate at several crystal frequencies, ref. the Crystal Spec. chapter.

Self-resonant frequency (SFR) must be > 2.7 GHz

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 29 of 32

March 2006

PCB layout example

Figure 19 shows a PCB layout example for the application schematic in Figure 18.

A double-sided FR-4 board of 1.6mm thickness is used. This PCB has ground planes on both
bottom layer and top layer to ensure good grounding of critical component. Additionally,
there are ground areas on the component side of the board to ensure sufficient grounding of
critical components. A large number of via holes connect the top layer ground areas to the
bottom layer ground plane.

Top silk screen

No components in bottom layer

Top view

Bottom view

Figure 19 nRF2402 RF layout with single ended connection to 50

antenna and 0603 size

passive components

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.1

Page 30 of 32

March 2006

DEFINITIONS

Data sheet status

Objective product specification

This datasheet contains target specifications for product development.

Preliminary product
specification

This datasheet contains preliminary data; supplementary data may be
published from Nordic Semiconductor ASA later.

Product specification

This datasheet contains final product specifications. Nordic Semiconductor
ASA reserves the right to make changes at any time without notice in order to
improve design and supply the best possible product.

Limiting values

Stress above one or more of the limiting values may cause permanent damage to the device. These are stress
ratings only and operation of the device at these or at any other conditions above those given in the
Specifications sections of the specification is not implied. Exposure to limiting values for extended periods may
affect device reliability.

Application information

Where application information is given, it is advisory and does not form part of the specification.

Table 19. Definitions.

Nordic Semiconductor ASA reserves the right to make changes without further notice to the
product to improve reliability, function or design. Nordic Semiconductor does not assume
any liability arising out of the application or use of any product or circuits described herein.

LIFE SUPPORT APPLICATIONS

These products are not designed for use in life support appliances, devices, or systems where
malfunction of these products can reasonably be expected to result in personal injury. Nordic
Semiconductor ASA customers using or selling these products for use in such applications do
so at their own risk and agree to fully indemnify Nordic Semiconductor ASA for any
damages resulting from such improper use or sale.

Product Specification: Revision Date: 17.03.2006.

Datasheet order code: 170306-nRF2402.

All rights reserved ®. Reproduction in whole or in part is prohibited without the prior written
permission of the copyright holder.

PRODUCT SPECIFICATION

nRF2402 Single Chip 2.4 GHz Radio Transmitter

Nordic Semiconductor ASA -

Vestre Rosten 81, N-7075 Tiller, Norway -

Phone +4772898900

- Fax +4772898989

Revision: 2.0

Page 32 of 32

April 2005

Nordic Semiconductor ASA World Wide Distributors

For Your nearest dealer, please see http://www.nordicsemi.no

Main Office:

Vestre Rosten 81, N-7075 Tiller, Norway

Phone: +47 72 89 89 00, Fax: +47 72 89 89 89

Visit the Nordic Semiconductor ASA web site at http://www.nordicsemi.no

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: NRF2402G

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: NRF2402G