CN217590826U - Be applied to auxiliary test equipment of WIFI radio frequency front end module chip - Google Patents

Be applied to auxiliary test equipment of WIFI radio frequency front end module chip Download PDF

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Publication number
CN217590826U
CN217590826U CN202221844128.2U CN202221844128U CN217590826U CN 217590826 U CN217590826 U CN 217590826U CN 202221844128 U CN202221844128 U CN 202221844128U CN 217590826 U CN217590826 U CN 217590826U
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radio frequency
electrically connected
port
test
circulator
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夏文泽
崔嘉
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Beijing Weijie Chuangxin Precision Measurement Technology Co ltd
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Beijing Weijie Chuangxin Precision Measurement Technology Co ltd
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    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Abstract

The utility model discloses an auxiliary test equipment applied to a WIFI radio frequency front end module chip, which comprises a directional coupler, a circulator and a high-pass filter; the input end of the directional coupler is used for being electrically connected with an antenna port of the WIFI radio frequency front end module chip, the output end of the directional coupler is electrically connected with the 2 port of the circulator, and the 3 port of the circulator is used for being electrically connected with the first test port of the radio frequency test machine so as to test the emission performance of the antenna port of the WIFI radio frequency front end module chip; and the coupling end of the directional coupler is electrically connected with the input end of the high-pass filter. The antenna port transmitting end index and the receiving end index of the WIFI radio frequency front end module chip are divided into two ports for testing through the directional coupler and the circulator, and the requirement for the measurement dynamic range during the harmonic testing of the radio frequency testing machine is lowered through the combination of the directional coupler and the high-pass filter.

Description

Be applied to auxiliary test equipment of WIFI radio frequency front end module chip
Technical Field
The utility model belongs to the technical field of the chip test, more specifically relates to an auxiliary test equipment for WIFI radio frequency front end module chip.
Background
The design of radio frequency transceiver chips is mature and industrialized, radio frequency solutions provided by some semiconductor companies at home and abroad are widely applied in the field of wireless equipment, and the mass production test of chips is an essential process for ensuring the product quality.
At present, the mass production Test of the radio frequency front end chip adopts ATE (Automatic Test Equipment) to Test, and for some radio frequency module chips having a transceiving function at the same time, for example, a WIFI radio frequency front end module chip (hereinafter referred to as a chip), as shown in fig. 1, a TX to ANT path is a transmitting link of the chip, and an ANT to RX path is a receiving link of the chip, so that an ANT (antenna) end of the chip needs to perform a transmitting end performance Test and a receiving end performance Test. When the performance of a transmitting end of the radio frequency WIFI module chip is tested, the output power of an ANT end can reach more than 30 dBm; when the performance of the receiving end of the chip is tested, the minimum input power of the ANT end can reach below-20 dBm, so that the power transceiving range of the tester can reach above 50 dBm. If the tester is directly connected with the ANT end of the ATE for testing, the tester cannot meet the power index requirements of the transmitting end and the receiving end at the same time.
The second harmonic and third harmonic test of the transmitting end of the radio frequency chip is used as an indispensable test index in the mass production test of the radio frequency chip, for the chip working at 2.5 GHz, the frequency value of the third harmonic can reach 7.5 GHz, the frequency index of the existing test machine can meet the frequency index, but the main frequency signal of part of products is more than 30 dBm, the harmonic signal can be less than-50 dBm, the difference between the main frequency power and the harmonic power of the signal is larger at the moment, the requirement on the measurement dynamic range of the test machine is very high, and the measurement dynamic range of the signal refers to the ratio of the maximum value and the minimum value of the signal power which can be changed at the same measurement moment. Except for a customized radio frequency tester in a high-end application field, the frequency spectrum index of the existing radio frequency tester is usually 10 MHz to 8 GHz, the radio frequency transceiving power index is usually-60 to 10 dBm, and the measurement dynamic range is 70 dBm, so that the test requirement index can not be met.
Therefore, the auxiliary test equipment applied to the WIFI radio frequency front-end module chip is expected to be invented, and the requirement on the measurement dynamic range of a radio frequency test machine during harmonic wave test can be effectively reduced.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a be applied to auxiliary test equipment of WIFI radio frequency front end module chip to the measurement dynamic range requirement of radio frequency test machine when reducing the harmonic test.
In order to achieve the above object, the utility model provides an auxiliary test equipment applied to a WIFI radio frequency front end module chip, which comprises a directional coupler, a circulator and a high-pass filter;
the input end of the directional coupler is used for being electrically connected with an antenna port of a WIFI radio frequency front end module chip, the output end of the directional coupler is electrically connected with a port 2 of the circulator, a port 3 of the circulator is used for being electrically connected with a first test port of a radio frequency test machine so as to test the transmitting performance of the antenna port of the WIFI radio frequency front end module chip, and a port 1 of the circulator is used for being electrically connected with a second test port of the radio frequency test machine so as to test the receiving performance of the antenna port of the WIFI radio frequency front end module chip;
the coupling end of the directional coupler is electrically connected with the input end of the high-pass filter, and the output end of the high-pass filter is electrically connected with the third test port of the radio frequency test machine so as to test the harmonic signals of the emission performance of the WIFI radio frequency front-end module chip.
Optionally, the method further comprises: an ANT end double female head, an MSR end double female head, an SRC end double female head and a HARM end double female head;
one female head of the ANT-end double female heads is electrically connected with the input end of the directional coupler, and the other female head is used for being electrically connected with an antenna port of the WIFI radio frequency front-end module chip;
one female head of the double female heads at the MSR end is electrically connected with the 3 port of the circulator, and the other female head is used for being electrically connected with a first test port of the radio frequency test machine;
one female head of the SRC end double female heads is electrically connected with a port 1 of the circulator, and the other female head is used for being electrically connected with a second test port of the radio frequency test machine;
and one of the two HARM-end female heads is electrically connected with the output end of the high-pass filter, and the other female head is used for being electrically connected with a third test port of the radio frequency tester.
Optionally, the method further comprises: a power attenuator;
the input end of the power attenuator is electrically connected with the other female head of the MSR end double female heads, and the output end of the power attenuator is electrically connected with a first test port of the radio frequency test machine.
Optionally, the method further comprises: double male heads;
the two female heads at the ANT end are electrically connected with the input end of the directional coupler through the two male heads.
Optionally, the method further comprises: a first radio frequency line, a second radio frequency line, a third radio frequency line, a fourth radio frequency line and a fifth radio frequency line;
the output end of the directional coupler is electrically connected with the 2 port of the circulator through the first radio frequency line;
the 3 port of the circulator is electrically connected with the MSR end double female heads through the second radio frequency wire;
the port 1 of the circulator is electrically connected with the SRC end double female heads through the third radio frequency line;
the coupling end of the directional coupler is electrically connected with the input end of the high-pass filter through the fourth radio frequency line;
and the output end of the high-pass filter is electrically connected with the HARM-end double female head through the fifth radio frequency wire.
Optionally, the method further comprises: a fifth radio frequency line;
and an antenna port of the WIFI radio frequency front-end module chip is electrically connected with the ANT-end double female heads through the fifth radio frequency line.
The beneficial effects of the utility model reside in that:
the utility model discloses an auxiliary test equipment, including directional coupler, circulator and high pass filter, fall into two port tests with the antenna port transmitting terminal index and the receiving terminal index of WIFI radio frequency front end module chip through directional coupler and circulator to through directional coupler, high pass filter's combination, measurement dynamic range requirement when having reduced radio frequency test machine harmonic test.
Other features and advantages of the present invention will be described in detail in the detailed description which follows.
Drawings
The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts throughout the exemplary embodiments of the present invention.
Fig. 1 shows a schematic structural diagram of a radio frequency WIFI module chip according to the prior art.
Fig. 2 shows a schematic structure diagram of an auxiliary test device applied to a WIFI radio frequency front end module chip according to an embodiment of the present invention.
Description of the reference numerals
1. A directional coupler; 2. a circulator; 3. a high-pass filter; 4. a power attenuator; 5. a first radio frequency line; 6. a second radio frequency line; 7. a third radio frequency line; 8. a fifth radio frequency line; 9. the ANT end is double female; 10. MSR end double female; 11. SRC end double female head; 12. a HARM end double female head; 13. double male heads; 14. a fourth radio frequency line.
Detailed Description
Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
According to the utility model discloses an auxiliary test equipment who is applied to WIFI radio frequency front end module chip, including directional coupler, circulator and high pass filter;
the input end of the directional coupler is electrically connected with the antenna port of the WIFI radio frequency front end module chip, the output end of the directional coupler is electrically connected with the 2 port of the circulator, the 3 port of the circulator is electrically connected with the first test port of the radio frequency test machine to test the emission performance of the antenna port of the WIFI radio frequency front end module chip, and the 1 port of the circulator is electrically connected with the second test port of the radio frequency test machine to test the receiving performance of the antenna port of the WIFI radio frequency front end module chip;
the coupling end of the directional coupler is electrically connected with the input end of the high-pass filter, and the output end of the high-pass filter is electrically connected with the third test port of the radio frequency test machine so as to test the harmonic signals of the emission performance of the WIFI radio frequency front-end module chip.
Specifically, the utility model discloses an auxiliary test equipment, including directional coupler, circulator and high pass filter, fall into two port tests with the antenna port transmitting terminal index and the receiving terminal index of WIFI radio frequency front end module chip through directional coupler and circulator to through directional coupler, high pass filter's combination, measurement dynamic range requirement when having reduced the test of radio frequency test machine harmonic.
In one example, the auxiliary test apparatus further comprises: an ANT end double female head, an MSR end double female head, an SRC end double female head and a HARM end double female head;
one female head of the ANT-end double female heads is electrically connected with the input end of the directional coupler, and the other female head is used for being electrically connected with an antenna port of the WIFI radio frequency front-end module chip;
one female head of the double female heads at the MSR end is electrically connected with the port 3 of the circulator, and the other female head is used for being electrically connected with a first test port of the radio frequency test machine;
one female head of the SRC end double female heads is electrically connected with a port 1 of the circulator, and the other female head is used for being electrically connected with a second test port of the radio frequency test machine;
one of the two HARM-end female heads is electrically connected with the output end of the high-pass filter, and the other female head is used for being electrically connected with a third test port of the radio frequency tester.
Specifically, the auxiliary test apparatus further includes: the dual female head of ANT end, the dual female head of MSR end, the dual female head of SRC end and the dual female head of HARM, wherein, when SRC end was as the signal emission end of radio frequency test machine, also can satisfy the transmitting power requirement.
In one example, the auxiliary test apparatus further comprises: a power attenuator;
the input end of the power attenuator is electrically connected with the other female head of the MSR end double female heads, and the output end of the power attenuator is electrically connected with a first test port of the radio frequency test machine.
Specifically, the utility model discloses an input of power attenuator among the auxiliary test equipment is connected with another female first electricity of two female heads in MSR end, and the output is used for being connected with the first test port electricity of radio frequency test machine, has effectively reduced the measurement power index requirement of radio frequency test machine.
In one example, the auxiliary test apparatus further comprises: double male heads;
the double female heads at the ANT end are electrically connected with the input end of the directional coupler through the double male heads.
In one example, the auxiliary test apparatus further comprises: a first radio frequency line, a second radio frequency line, a third radio frequency line, a fourth radio frequency line and a fifth radio frequency line;
the output end of the directional coupler is electrically connected with the port 2 of the circulator through a first radio frequency wire;
the 3 port of the circulator is electrically connected with the MSR end double female heads through a second radio frequency wire;
the port 1 of the circulator is electrically connected with the SRC end double female heads through a third radio frequency line;
the coupling end of the directional coupler is electrically connected with the input end of the high-pass filter through a fourth radio frequency line;
and the output end of the high-pass filter is electrically connected with the HARM-end double female head through a fifth radio frequency line.
In one example, the auxiliary test apparatus further comprises: a fifth radio frequency line;
and an antenna port of the WIFI radio frequency front end module chip is electrically connected with the ANT end double female heads through a fifth radio frequency line.
Examples
As shown in fig. 2, before the chip is formally tested, each port of the tester needs to be calibrated to eliminate the measurement loss caused by the signal passing through the external rf line and the external device.
Leading out a chip port to a radio frequency line through a chip test fixture and a PCB (printed Circuit Board), electrically connecting one female head of an ANT end double female head 9 with the input end of the directional coupler 1, and electrically connecting the other female head with an antenna port of a WIFI radio frequency front end module chip; one female head of the double female heads 10 at the MSR end is electrically connected with the port 3 of the circulator 2, and the other female head is used for being electrically connected with a first test port of a radio frequency test machine; one female head of the SRC-end double female heads 11 is electrically connected with a port 1 of the circulator 2, and the other female head is used for being electrically connected with a second test port of the radio frequency test machine; one of the two HARM-terminal female heads 12 is electrically connected with the output end of the high-pass filter 3, and the other female head is used for being electrically connected with a third test port of the radio frequency tester. The output end of the directional coupler 1 is electrically connected with the port 2 of the circulator 2 through a first radio frequency wire 5; the port 3 of the circulator 2 is electrically connected with the MSR end double female head 10 through a second radio frequency wire 6; the port 1 of the circulator 2 is electrically connected with the SRC end double female heads 11 through a third radio frequency wire 7; the coupling end of the directional coupler 1 is electrically connected with the input end of the high-pass filter 3 through a fourth radio frequency line 14; the output end of the high-pass filter 3 is electrically connected with a HARM-end double female head 12 through a fifth radio frequency wire 8. The ANT end double female head 9 is electrically connected with the input end of the directional coupler 1 through the double male head 13. The MSR end double female heads 10 of the auxiliary equipment can select a proper power attenuator 4 to be connected according to output power, and then the SRC end double female heads 11 and the MSR end double female heads 10 are respectively connected to two test ports of a radio frequency test machine, so that the radio frequency test machine can test the transmitting end performance and the receiving end performance of an antenna port of the WIFI radio frequency front end module chip through the measurement ports.
When the chip works in a transmitting state, the testing machine transmits signals from a TX port of the chip, antenna port signals enter the auxiliary equipment through the ANT-end double female heads 9 of the auxiliary equipment, a part of the signals reach the circulator 2 through the directional coupler 1, the output port of the circulator 2 is the MSR-end double female head 10, the MSR-end double female head 10 is connected with a proper power attenuator 4, the radio frequency testing machine can measure the antenna port signals of the chip, and the requirement of a receiving power index of the radio frequency testing machine is lowered.
When the chip works in a receiving state, a radio frequency signal of the tester enters the auxiliary device through the SRC end double female heads 11, the signal enters the circulator 2 and is output to the ANT end double female heads 9 through the directional coupler 1, and at the moment, a receiving end performance test can be carried out on an RX port of the chip.
When measuring the harmonic performance of the transmitting end of the chip, the signal of the tester enters from the TX port, and the signal is amplified through the chip, at this time, the harmonic signal of the ANT-end double female head 9 enters the high-pass filter 3 through the coupling port of the directional coupler 1 in the auxiliary device to filter the main frequency signal in the signal, so as to reduce the dynamic range of the tester during the harmonic test, and at this time, the tester can measure the harmonic signal after the filtering processing at the HARM-end double female head end 12 of the auxiliary device.
According to the requirement of the measurement principle, an appropriate part is selected for developing the device, and the specific steps are as follows:
Figure 514950DEST_PATH_IMAGE001
the chip port is led out to a radio frequency line through the chip test fixture and the PCB, the ANT end of the chip is connected with the ANT end of the auxiliary equipment through a 50 omega radio frequency line, the other radio frequency ports are respectively connected to different radio frequency resource ports of a radio frequency test machine, the chip is enabled to enter a working state through power supply of the test machine, and radio frequency signals are emitted to conduct testing.
After improvement, the measurement port of the radio frequency test machine is used for respectively testing the performance of the transmitting end and the performance of the receiving end of the antenna port of the WIFI radio frequency front-end module chip, and the radio frequency test machine serving as a signal transmitting end completely meets the power index of the existing test machine in the market;
after improvement, the receiving power index of a measuring port of the radio frequency tester can be reduced to about 5dBm, and the radio frequency tester serving as a signal receiving end completely meets the power index of the existing tester in the market;
after improvement, the measurement dynamic range of the radio frequency tester meets the requirement of harmonic wave test.
While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims (6)

1. An auxiliary test device applied to a WIFI radio frequency front end module chip is characterized by comprising a directional coupler, a circulator and a high-pass filter;
the input end of the directional coupler is used for being electrically connected with an antenna port of a WIFI radio frequency front end module chip, the output end of the directional coupler is electrically connected with a port 2 of the circulator, a port 3 of the circulator is used for being electrically connected with a first test port of a radio frequency test machine so as to test the transmitting performance of the antenna port of the WIFI radio frequency front end module chip, and a port 1 of the circulator is used for being electrically connected with a second test port of the radio frequency test machine so as to test the receiving performance of the antenna port of the WIFI radio frequency front end module chip;
the coupling end of the directional coupler is electrically connected with the input end of the high-pass filter, and the output end of the high-pass filter is electrically connected with the third test port of the radio frequency test machine so as to test the harmonic signals of the emission performance of the WIFI radio frequency front-end module chip.
2. The auxiliary test equipment applied to the WIFI radio frequency front end module chip of claim 1, further comprising: an ANT end double female head, an MSR end double female head, an SRC end double female head and a HARM end double female head;
one female head of the ANT-end double female heads is electrically connected with the input end of the directional coupler, and the other female head is used for being electrically connected with an antenna port of the WIFI radio frequency front-end module chip;
one female head of the double female heads at the MSR end is electrically connected with the 3 port of the circulator, and the other female head is used for being electrically connected with a first test port of the radio frequency test machine;
one female head of the SRC end double female heads is electrically connected with a port 1 of the circulator, and the other female head is used for being electrically connected with a second test port of the radio frequency test machine;
and one of the two HARM-end female heads is electrically connected with the output end of the high-pass filter, and the other female head is used for being electrically connected with a third test port of the radio frequency tester.
3. The auxiliary test equipment applied to the WIFI radio frequency front end module chip of claim 2, further comprising: a power attenuator;
the input end of the power attenuator is electrically connected with the other female head of the MSR-end double female heads, and the output end of the power attenuator is electrically connected with a first test port of the radio frequency tester.
4. The auxiliary test equipment applied to the WIFI radio frequency front end module chip of claim 2, further comprising: double male heads;
the two female heads at the ANT end are electrically connected with the input end of the directional coupler through the two male heads.
5. The auxiliary test equipment applied to the WIFI radio frequency front end module chip of claim 2, further comprising: a first radio frequency line, a second radio frequency line, a third radio frequency line, a fourth radio frequency line and a fifth radio frequency line;
the output end of the directional coupler is electrically connected with the 2 port of the circulator through the first radio frequency wire;
the 3 port of the circulator is electrically connected with the MSR end double female heads through the second radio frequency wire;
the port 1 of the circulator is electrically connected with the SRC end double female heads through the third radio frequency line;
the coupling end of the directional coupler is electrically connected with the input end of the high-pass filter through the fourth radio frequency line;
and the output end of the high-pass filter is electrically connected with the HARM-end double female head through the fifth radio frequency wire.
6. The auxiliary test equipment applied to the WIFI radio frequency front end module chip of claim 2, further comprising: a sixth radio frequency line;
and an antenna port of the WIFI radio frequency front-end module chip is electrically connected with the ANT end double female heads through the sixth radio frequency line.
CN202221844128.2U 2022-07-18 2022-07-18 Be applied to auxiliary test equipment of WIFI radio frequency front end module chip Active CN217590826U (en)

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CN202221844128.2U CN217590826U (en) 2022-07-18 2022-07-18 Be applied to auxiliary test equipment of WIFI radio frequency front end module chip

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