Shenzhen ESP-C20 2.4GHz Wi-Fi and BLE5.0 Combo Module Owner’s Manual

: September 20, 2024
: Shenzhen

Table of Contents

ESP-C20 2.4GHz Wi-Fi and BLE5.0 Combo Module
Product Specification
Specifications
Product Usage Instructions
1. Powering the Module
2. Connecting to Wi-Fi
- Frequently Asked Questions (FAQ)
Q: Can the module be used in outdoor environments?
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)

ESP-C20 2.4GHz Wi-Fi and BLE5.0 Combo Module

Product Specification

Model: ESP-C20

Module Type: 2.4GHz Wi-Fi and BLE5.0 Combo
Module

Version: 1.0

Date: Feb. 20, 2023

Specifications

Chip: ESP32-C3
Module Size: 18mm x 20mm x 3mm
Flash: 32M bit embedded flash (default)
ROM: 384KB
SRAM: 400KB
Wi-Fi Features:
- IEEE 802.11 b/g/n-compliant
- Operating Channel Frequency Range: 2412 – 2484 MHz
- Data Rate: up to 150 Mbps
- Supports various modes including Station mode, Soft-AP mode,
  and promiscuous mode
Bluetooth Features:
- Bluetooth LE: Bluetooth 5, Bluetooth mesh
- Speed: 125 Kbps, 500 Kbps, 1 Mbps, 2 Mbps
- Advertising extensions
Peripheral Interfaces:
- GPIO 15, UART 2, IIC, SPI, EN, PWM * 6, ADC
- Working Temperature: -40°C to 85°C

Product Usage Instructions

1. Powering the Module

Connect the VCC pin to a power source of 3.3V/500mA.

2. Connecting to Wi-Fi

To connect to a Wi-Fi network, configure the appropriate
settings using the provided interfaces.

Frequently Asked Questions (FAQ)

Q: Can the module be used in outdoor environments?

A: The module has a working temperature range of -40°C to 85°C,
making it suitable for outdoor use within this temperature
range.

ESP-C20

Product Specification

—-2.4GHz Wi-Fi and BLE5.0 Combo Module

Version: 1.0

Date: Feb.20, 2023

Features
General Chip: ESP32-C3 Module Size:18mm20mm3mm 32M bit embedded flash (default) 384KB ROM 400KB SRAM
Wi-Fi Features IEEE 802.11 b/g/n-compliant Center frequency range of operating channel: 2412 ~ 2484 MHz Supports 20 MHz, 40 MHz bandwidth in 2.4 GHz band 1T1R mode with data rate up to 150 Mbps TX/RX A-MPDU, TX/RX A-MSDU Immediate Block ACK Fragmentation and defragmentation Automatic Beacon monitoring (hardware TSF) 4 X virtual Wi-Fi interfaces Simultaneous support for Infrastructure BSS in Station mode, Soft-AP mode, Station + Soft-AP mode, and promiscuous mode
Bluetooth Features Bluetooth LE: Bluetooth 5, Bluetooth mesh Speed: 125 Kbps, 500 Kbps, 1 Mbps, 2 Mbps Advertising extensions Multiple advertisement sets Channel selection algorithm #2
Peripheral Interfaces GPIO 15; UART 2; IIC ;

SPI; EN ; PWM x 6 ; ADC; Working Temperature: -40-85
Applications

Serial transparent transmission; Wi-Fi prober; Smart power plug/Smart LED light; Mesh networks; Sensor networks; Over-the-top (OTT) devices; Wireless location system beacon; Industrial field bus;
Module Type

Name ESP-C20-N2 ESP-C20-N4 ESP-C20-N8

Flash 16M bit 32M bit 64M bit

Antenna U.FL IPEX U.FL IPEX U.FL IPEX

Module Structure

Update Record
Date 2023-02-20

Version V1.0

Update First released

Table of Contents
1. Introduction ……………………………………………………………………………………………………….. 1 2. Interface Definition …………………………………………………………………………………………….. 3 3. Size and Layout ………………………………………………………………………………………………….. 5 4. Electronica Characteristics …………………………………………………………………………………… 6 5. Power Consumption ……………………………………………………………………………………………. 6 6. Wi-Fi RF Characteristics……………………………………………………………………………………… 7 7. Bluetooth LE Radio…………………………………………………………………………………………….. 9 8. Recommended Sold Temperature Curve ……………………………………………………………… 10 9. Minimum User System………………………………………………………………………………………. 11 10. Recommended Layout Design ………………………………………………………………………….. 12 11. Peripheral Design Suggestion …………………………………………………………………………… 13 12. Product Handling…………………………………………………………………………………………….. 13 13. U.FL RF Connector …………………………………………………………………………………………. 14 14. Packing Instruction………………………………………………………………………………………….. 14 15. Module Schematic …………………………………………………………………………………………… 16

ESP-C20 User Manual
1. Introduction
ESP-C20 Wi-Fi and BLE coexistence Module is a highly integrated single-chip low power 802.11bgn Wireless LAN (WLAN) network controller. It combines a RISC CPU, WLAN MAC, a 1T1R capable WLAN baseband, RF, and Bluetooth in a single chip. It also provides a bunch of configurable GPIO, which are configured as digital peripherals for different applications and control usage. ESP-C20 Module use ESP32-C3 as Wi-Fi and BLE coexistence SOC chip. ESP-C20 Module integrates internal memories for complete Wi-Fi protocol functions. The embedded memory configuration also provides convenient application developments. ESP-C20 module supports the standard IEEE802.11 b/g/n/e/i protocol and the complete TCP/IP protocol stack. User can use it to add the Wi-Fi function for the installed devices, and also can be viewed as an independent network controller. Anyway, ESP-C20 Wi-Fi module provides many probabilities with the best price.

Fig.1.1 ESP-C20 Module Structure

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Technical parameters for ESP-C20 are listed as follows.

Table.1.1 ESP-C20 Parameters

Type Wi-Fi BLE Hardware Software

Item Frequency
Transmit power
Receiver sensitivity
EVM
Antenna RF power control range CPU Interface Working voltage Working temperature Environment temperature Shape Wi-Fi working mode Security mode Update firmware Software develop Network protocol

Parameter 2.4G~2.5G (2412M~2484M) 802.11b: +20.5 dBm 802.11g: +19 dBm 802.11n: +17.5 dBm 802.11b: -89 dBm (11Mbps) 802.11g: -77 dBm54Mbps 802.11n: -74 dBmMCS7 -25dB @802.11b,11Mbps @21dBm -28dB @802.11n,54Mbps @19dBm -30dB @802.11n,HT40,MCS7 @18.5dBm U.FL -27~18dBm 32-bit RISC CPU UART/SDIO/SPI/I2C/GPIO/PWM 3.0V ~ 3.6V -40°C ~ 85°C -40°C ~ 105°C 18mm x 20mm x 3mm STA, Soft-AP and sniffer modes WPS / WEP / WPA / WPA2 / WPA3 UART Download SDK IPv4, TCP/UDP/HTTP/FTP/MQTT

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ESP-C20 User Manual
2. Interface Definition
ESP-C20 Wi-Fi & BLE module interface definition is shown as below

Fig.2.1 ESP-C20 Pins Definition
Working modes and pins function is shown in Table 2.1.
Table.2.1Working Mode

Mode UART Download Mode
Flash Boot Mode

IO9 Voltage Level LOW
HIGH (Default)

Num. 1 2 3 4 5 6 7

Pin Name VCC EN IO4 IO5 IO6 IO7 IO8

Table.2.2 Pins Function Definition

Type

Function

P Power, 3.3V/500mA Recommended

I/O Chip enable; Internal Pull-up. HIGH: enable the chip

I/O GPIO4, ADC1_CH4, MTMS, FSPIHD

I/O GPIO5, ADC2_CH0, MTDI, FSPIWP

I/O GPIO6,FSPICLK,MTCK

I/O GPIO7,FSPID,MTDO

I/O GPIO8

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7

IO8

I/O GPIO8

8

IO9

I/O GPIO9

9

GND

P Power, 3.3V/500mA Recommended

GPIO10, FSPICS0. When the value of eFuse bit

EFUSE_JTAG_SEL_ENABLE is 0, JTAG signals cannot be used.

10

IO10

I/O 1, if IO10 is 0, JTAG signals come from chip pins; if IO10 is 1, JTAG

signals cannot be used

11

RXD

I/O GPIO20,U0RXD

12

TXD

I/O GPIO21,U0TXD

13

IO18

I/O GPIO18,USB-D-

14

IO19

I/O GPIO19,USB-D+

15

IO3

I/O GPIO3, ADC1_CH3

16

IO2

I/O GPIO2, ADC1_CH2, FSPIQ, Internal Pull-up

17

IO1

I/O GPIO1,ADC1_CH1, XTAL_32K_N

18

IO0

I/O GPIO0,ADC1_CH1,XTAL_32K_P

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ESP-C20 User Manual
3. Size and Layout
Size for ESP-C20 can be shown as follows.
Fig.3.1 Shape for ESP-C20

(a) Vertical View

(b) Side View
Fig.3.2 Size for ESP-C20
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Fig. 3.3 PCB Layout for ESP-C20

4. Electronica Characteristics

Table.4.1 Electronica Characteristics

Parameter Store Temperature

Sold Temperature

Working Voltage

VIL

I/O

VIH VOL

VOH

Electrostatic

Release

Quantity (Human model)

Condition IPC/JEDEC J-STD-020 –
TAMB=25

Electrostatic

Release

Quantity (Machine model)

TAMB=25

Min -40
–
3.0 -0.3 0.75VDD 0.8VDD
–
–

Classical Normal
–
3.3 –
–
–

Max

Unit

150

260

3.6

V

0.25*VDD

VDD+0.3 0.1*VDD

V

–

2

KV

0.5

KV

5. Power Consumption

Table.5.1 Power Consumption

Parameter RX 11b /g/n, HT20

Min

Classical Max

Unit

–

82

mA

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RX 11n, HT40

TX 11b, 1Mbps @21dBm

TX 11g, 54Mbps @19dBm

–

TX 11n, HT20, MCS7, @18.5dBm

–

TX 11n, HT40, MCS7, @18.5dBm

–

Modem-sleep, CPU is powered on @80MHz

–

Light-sleep

–

Deep-sleep, RTC timer + RTC memory

–

Power off, CHIP_PU is set to low level

–

84

mA

–

350

mA

–

295

mA

–

290

mA

–

290

mA

15

–

mA

130

–

uA

5

–

uA

1

0

uA

The peak current consumption of ESP-C20 exceed 400mA when the module start work (RF calibration work consumes maximum current). Therefore, the recommended power supply is no less than 500mA. Note: 1. Active Mode: CPU and RF are all turned on. 2. Modem-sleep Mode: CPU is turned on. RF and baseband are turned off, but the communication is still connected. 3. Light-sleep Mode: CPU is turned off. RTC/external interrupt/MAC can wake up the chip. The communication is still connected. 4. Deep-sleep Mode: Only RTC is turned on.
6. Wi-Fi RF Characteristics
The data in the following table is gotten when voltage is 3.3V in the indoor temperature environment.

Table.6.1 Wi-Fi TX Characteristics

Parameter

Min

Classical Max

Input frequency

2412 –

2484

802.11b @1Mbps,11Mbps

–

20.5

–

802.11g @6Mbps

–

20.0

–

802.11g @54Mbps

–

18.0

–

802.11n,HT20 MCS0

–

19.0

–

Unit MHz dBm dBm dBm dBm

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802.11n,HT40 MCS0 EVM @11b,1Mbps@20dBm EVM @11g,54Mbps@19dBm EVM @11n,MCS7@18.5dBm EVM @11n, HT40, MCS7@18.5dBm

–

18.5

–

dBm

–

-24.5

–

dBm

–

-28

–

dBm

–

-30

–

dBm

–

-30.5

–

dBm

Parameter 802.11b,1Mbps 802.11b,11Mbps 802.11g,6Mbps 802.11g,54Mbps 802.11n,HT20,MCS0 802.11n,HT20,MCS3 802.11n,HT20,MCS7 802.11n,HT40,MCS0 802.11n,HT40,MCS3 802.11n,HT40,MCS7

Table.6.2 Wi-Fi RX Sensitivity

Min

Classical Max

Unit

–

-98

–

dBm

–

-88

–

dBm

–

-92

–

dBm

–

-76

–

dBm

–

-92

–

dBm

–

-85

–

dBm

–

-74

–

dBm

–

-90

–

dBm

–

-81

–

dBm

–

-71

–

dBm

Table.6.3 Wi-Fi RX Characteristics

Parameter MAX RX Level @11b,1Mbps

Min Classical Max

Unit

–

5

–

dBm

MAX RX Level @11b,11Mbps

–

5

–

dBm

MAX RX Level @11g,6Mbps

–

5

–

dBm

MAX RX Level @11g,54Mbps

–

0

–

dBm

MAX RX Level @11n,HT20,MCS0

–

5

–

dBm

MAX RX Level @11n,HT20,MCS7

–

0

–

dBm

MAX RX Level @11n,HT40,MCS0

–

5

–

dBm

MAX RX Level @11n,HT40,MCS7

–

0

–

dBm

RX Adjacent Channel Rejection@11b,1Mbps

–

35

–

dB

RX Adjacent Channel Rejection@11b,11Mbps

–

35

–

dB

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RX Adjacent Channel Rejection@11g,6Mbps

–

31

–

dB

RX Adjacent Channel Rejection@11g,54Mbps

–

14

–

dB

RX Adjacent Channel Rejection@11n,HT20,MCS0 –

31

–

dB

RX Adjacent Channel Rejection@11n,HT20,MCS7 –

13

–

dB

RX Adjacent Channel Rejection@11n,HT40,MCS0 –

19

–

dB

7. Bluetooth LE Radio

Table.7.1 TX Transmitter General Characteristics

Parameter Gain control power RF power control range In-band emissions @F-F0±3MHz, LE 1M In-band emissions @F-F0±>3MHz, LE 1M Modulation characteristics @ f1avg, LE 1M Modulation characteristics @f2max, LE 1M Carrier frequency offset, LE 1M In-band emissions @F-F0±5MHz, LE 2M In-band emissions @F-F0±>5MHz, LE 2M Modulation characteristics @ f1avg, LE 2M Modulation characteristics @f2max, LE 2M Carrier frequency offset, LE 2M In- band emissions @F-F0±3MHz, LE 500K In-band emissions @F-F0±>3MHz, LE 500K Modulation characteristics @ f1avg, LE 500K Modulation characteristics @f2max, LE 500K Carrier frequency offset, LE 500K Maximum received signal @30.8% PER

Min Classical Max Unit

–

3

–

dBm

-27 –

18

dBm

–

-41.95 –

dBm

–

-44.48 –

dBm

–

245

–

kHz

–

208

–

kHz

–

-9

–

kHz

–

-45.26 –

dBm

–

-47

–

dBm

–

497

–

kHz

–

398

–

kHz

–

-9

–

kHz

–

-41.3

–

dBm

–

-42.8

–

dBm

–

220

–

kHz

–

205

–

kHz

–

-11.9

–

kHz

–

10

–

dBm

Table.7.2 RX Transmitter General Characteristics

Parameter Sensitivity @30.8% PER

Min Classical Max Unit

–

-96

–

dBm

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ESP-C20 User Manual

Maximum received signal @30.8% PER

–

10

–

dBm

Co-channel C/I

–

8

–

dB

Image frequency

–

-29

–

dB

Adjacent channel to image frequency @F =Fimage+1 –

-38

1

M Adjacent channel to image frequency @F =Fimage-1 –

-34

–

dB

–

dB

Adjacent channel selectivity @ F =F0+1

–

-4

–

dB

Adjacent channel selectivity @ F =F0-1

–

-3

–

dB

Adjacent channel selectivity @ F F0+3

–

dB

Adjacent channel selectivity @ F F0-3

–

-39

–

dB

Sensitivity @30.8% PER

–

-93

–

dBm

Maximum received signal @30.8% PER

–

0

–

dBm

Co-channel C/I

–

10

–

dB

Image frequency

–

-27

–

dB

2 Adjacent channel to image frequency @F =Fimage+2 –

-39

M Adjacent channel to image frequency @F =Fimage-2 –

–

dB

–

dB

Adjacent channel selectivity @ F =F0+2

–

-7

–

dB

Adjacent channel selectivity @ F =F0-2

–

-7

–

dB

Adjacent channel selectivity @ F F0+6

–

-39

–

dB

Adjacent channel selectivity @ F F0-6

–

-39

–

dB

Sensitivity @30.8% PER

–

-104

–

dBm

Maximum received signal @30.8% PER

–

10

–

dBm

Co-channel C/I

–

2

–

dB

Image frequency

–

-34

1 2

Adjacent channel to image frequency @F =Fimage+1

–

-44

5 K

Adjacent channel to image frequency @F =Fimage-1

–

-37

Adjacent channel selectivity @ F =F0+2

–

-40

–

dB

–

dB

–

dB

–

dB

Adjacent channel selectivity @ F =F0-2

–

-42

–

dB

Adjacent channel selectivity @ F F0+3

–

dB

Adjacent channel selectivity @ F F0-3

–

-46

–

dB

8. Recommended Sold Temperature Curve
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ESP-C20 User Manual
(1) Reflow Times <= 2 times (Max.) (2) Max Rising Slope: 3/sec (3) Max Falling Slope: -3/sec (4) Over 217 Time: 60~120sec (5) Peak Temp:240~250
Fig.8.1 Recommended Reflow Profile
9. Minimum User System
This module can work just at 3.3V voltage condition:

Fig.9.1 Minimum System

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ESP-C20 User Manual
Note:
(1) The working voltage for module is DC 3.3V;
(2) The max current from IO of this module is 40mA;
(3) Wi-Fi module is at download mode: IO9 is LOW level, then module reset to power;
(4) Wi-Fi module is connected to RXD of the other MCU, and TXD is connected to RXD of the other MCU.
10. Recommended Layout Design
ESP-C20 module can be sold on PCB board directly. For the high RF performance for the device, please notice the placement of the module. There are three ways to use the module for Wi-Fi Module with PCB antenna. Solution 1: optical solution. The Wi-Fi module is placed on the side of the board, and the antennas are all exposed, and there is no metal material around the antenna, including wires, metal casings, weight plates, and the like.
Solution 2: sub-optical solution. The Wi-Fi module is placed on the side of the board, and the antenna below is hollowed out. There is a gap of not less than 5 mm reserved with the PCB, and there is no metal material around the antenna, including wires, metal casings, weight plates, and the like.
Solution 3: The Wi-Fi module is placed on the side of the board, and the PCB area under the antenna is empty, and copper cannot be laid.

Fig.10.1 Solution 1

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Fig.10.2 Solution 2

Fig.10.3 Solution 3
11. Peripheral Design Suggestion
Wi-Fi module is already integrated into high-speed GPIO and Peripheral interface, which may be generated the switch noise. If there is a high request for the power consumption and EMI characteristics, it is suggested to connect a serial 10~100 ohm resistance, which can suppress overshoot when switching power supply, and can smooth signal. At the same time, it also can prevent electrostatic discharge (ESD).
12. Product Handling
12.1 Storage Conditions

The products sealed in moisture barrier bags (MBB) should be stored in a non- condensing atmospheric environment of < 40 °C and 90%RH. The module is rated at the moisture sensitivity level (MSL) of 3. After unpacking, the module must be soldered within 168 hours with the factory conditions 25±5 °C and 60%RH. If the above conditions are not met, the module needs to be baked.

12.2 Electrostatic Discharge (ESD)

· Human body model (HBM): ±2000 V

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· Charged-device model (CDM): ±500 V
13. U.FL RF Connector
ESP-C20 module use U.FL type RF connector for external antenna connection. (IPEX V1.0).

Fig.13.1 U.FL RF Connector
14. Packing Instruction
The product is packed in a tray, as shown in the following figure.
The size of the single box is: 340 x 360 x 60mm, and 800 pieces module is in the box. And the outer box size is 355 x 375 x 325mm, including 5 single box which include 4000 pieces module.

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Fig.14.1 Module Package

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15. Module Schematic

ESP-C20 User Manual

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FCC Statement This device complies with part 15 of the FCC rules. Operation is subject to the following two conditions: (1) thi s device may not cause harmful interference, and (2) this device must accept any interference received, incl uding interference that may cause undesired operation. Changes or modifications not expressly approved by the party responsible for compliance could void the user’ s authority to operate the equipment. NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursua nt to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful inte rference in a residential installation. This equipment generates uses and can radiate radio frequency energy a nd, if not installed and used in accordance with the instructions, may cause harmful interference to radio com munications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turn ing the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: – Reorient or relocate the receivingantenna. – Increase the separation between the equipment and receiver. -Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. -Consult the dealer or an experienced radio/TV technician for help important announcement Important Note: Radiation Exposure Statement This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator and your body. This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter. Country Code selection feature to be disabled for products marketed to the US/Canada. This device is intended only for OEM integrators under the following conditions: 1. The antenna must be installed such that 20 cm is maintained between the antenna and users, and 2. The transmitter module may not be co-located with any other transmitter or antenna, 3. For all products market in US, OEM has to limit the operation channels in CH1 to CH11 for 2.4G band
by supplied firmware programming tool. OEM shall not supply any tool or info to the end-user regarding to Regulatory Domain change. (if modular only test Channel 1-11) As long as the three conditions above are met, further transmitter testing will not be required. However, the OEM integrator is still responsible for testing their end-product for any additional compliance requirements required with this module installed.
Important Note: In the event that these conditions cannot be met (for example certain laptop configurations or co-location with another transmitter), then the FCC authorization is no longer considered valid and the FCC ID cannot be used on the final product. In these circumstances, the OEM integrator will be responsible for re-evaluating the end product (including the transmitter) and obtaining a separate FCC authorization.
End Product Labeling The final end product must be labeled in a visible area with the following” Contains FCC ID: 2BB77-ESP-C20″
Manual Information to the End User The OEM integrator has to be aware not to provide information to the end user regarding how to install or remove this RF module in the user’s manual of the end product which integrates this module. The end user manual shall include all required regulatory information/warning as show in this manual.

Integration instructions for host product manufacturers according to KDB 996369 D03 OEM Manual v01 2.2 List of applicable FCC rules

CFR 47 FCC PART 15 SUBPART C has been investigated. It is applicable to the modular transmitter
2.3 Specific operational use conditions

This module is stand-alone modular. If the end product will involve the Multiple simultaneously transmitting condition or different operational conditions for a stand-alone modular transmitter in a host, host manufacturer have to consult with module manufacturer for the installation method in end system.
2.4 Limited module procedures
Not applicable
2.5 Trace antenna designs
Not applicable
2.6 RF exposure considerations

This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator & your body.
2.7 Antennas This radio transmitter FCC ID:2BB77-ESP-C20 has been approved by Federal Communications Commission to operate with the
antenna types listed below, with the maximum permissible gain indicated. Antenna types not included in this list that have a gain greater than the maximum gain indicated for any type listed are strictly prohibited for use with this device.

Antenna No. BT/2.4GWiFi

Model No. of antenna: /

Type of antenna: FPC Antenna

Gain of the antenna (Max.) Frequency range: 2.94dBi for 2400-2500MHz;

2.8 Label and compliance information
The final end product must be labeled in a visible area with the following” Contains FCC ID:2BB77-ESP-C20″.
2.9 Information on test modes and additional testing requirements
Host manufacturer is strongly recommended to confirm compliance with FCC requirements for the transmitter when the module is installed in the host.
2.10 Additional testing, Part 15 Subpart B disclaimer
Host manufacturer is responsible for compliance of the host system with module installed with all other applicable requirements for the system such as Part 15 B. 2.11Note EMI Considerations Host manufacture is recommended to use D04 Module Integration Guide recommending as “best practice” RF design engineering testing and evaluation in case non-linear interactions generate additional non-compliant limits due to module placement to host components or properties. 2.12How to make changes This module is stand-alone modular. If the end product will involve the Multiple simultaneously transmitting condition or different operational conditions for a stand-alone modular transmitter in a host, host manufacturer have to consult with module manufacturer for the installation method in end system. According to the KDB 996369 D02 Q&A Q12, that a host manufacture only needs to do an evaluation (i.e., no C2PC required when no emission exceeds the limit of any individual device (including unintentional radiators) as a composite. The host manufacturer must fix any failure.