LR1121IMLTRT

SEMTECHExtended

-108dBm -40℃~+85℃ 1.8V~3.7V 101.5Kbps 13dBm 150MHz~960MHz、1.9GHz~2.1GHz、2.4GHz~2.5GHz 26mA 7.8mA LoRa Power-on reset function、Power-off reset function SPI transceiver QFN-32-EP(5x5) RF Transceiver ICs ROHS

Datasheet JLCPCB LCSC

Part id: semtech/LR1121IMLTRT
Category: RF Transceiver ICs
Package: QFN-32-EP(5x5)
Pins: 33
In stock: 1,742 at JLCPCB (C7498014)
Used on: 5 open-source boards

Overview

The LR1121IMLTRT is a RF Transceiver IC made by SEMTECH in a QFN-32-EP(5x5) package with 33 pins. -108dBm -40℃~+85℃ 1.8V~3.7V 101.5Kbps 13dBm 150MHz~960MHz、1.9GHz~2.1GHz、2.4GHz~2.5GHz 26mA 7.8mA LoRa Power-on reset function、Power-off reset function SPI transceiver QFN-32-EP(5x5) RF Transceiver ICs ROHS.

PCBKit's library has its KiCad symbol (Analog & Interface:LR1121IMLTRT, from CERN's library) and its footprint (ICs And Semiconductors SMD:QFN50P500X500X100-33N-S380, from CERN's library), ready for a KiCad board. 1,742 are in stock at JLCPCB (part C7498014). 5 open-source boards in 5 repositories on GitHub use it.

Symbol

Analog & Interface:LR1121IMLTRTFrom CERN's library

Footprint

ICs And Semiconductors SMD:QFN50P500X500X100-33N-S380From CERN's library

From the datasheet

Supply, least: 1.8 V · VDD, recommended operating min · p. 12
Supply, most: 3.7 V · VDD, recommended operating max · p. 12
Supply, absolute maximum: 3.9 V · VDD, absolute maximum · p. 12
Works from: -40 °C · Ambient temperature under bias min · p. 12
Works up to: 85 °C · Ambient temperature under bias max · p. 12
Takes working: 5.7 mA · Receive, LoRa SF12 125kHz sub-GHz, DC-DC, typical · p. 14
Takes at most: 118 mA · Transmit +22dBm, 868/915MHz HP PA, typical · p. 15
Takes asleep: 800 nA · Power down, typical · p. 14
Takes asleep: 1.5 µA · Sleep with LFXOSC RTC, no RAM retained, typical · p. 14
Junction to air (QFN32): 26.7 K/W · Junction to ambient, 4-layer board with 9 thermal vias · p. 32

What it is and has

Frequency bands: 150 - 960MHz sub-GHz, 1.9-2.1GHz S-band, 2.4GHz ISM · p. 8
Sub-GHz power amplifiers: +22dBm high power, +15dBm high efficiency · p. 8
LR-FHSS: Transmitter with intra-packet hopping · p. 8
Sigfox: Transceiver; RC1 to RC7; downlink · p. 8
Power management: Power On Reset, brown-out detection, low battery indication · p. 8
Battery measurement: Battery voltage measurement · p. 8
HF RC oscillator: 32MHz · p. 8
HF crystal oscillator: 32MHz · p. 8
Package: QFN32, Pb-free, Halogen free, RoHS/WEEE compliant · p. 2

Specifications

Parameter	Conditions	As printed	Page
Supply voltage VDDmr		min -0.5 · max 3.9 V	12
Temperature Tmr		min -55 · max 125 °C	12
RF Input level Pmr		max 10 dBm	12
Supply voltage VDDop		min 1.8 · max 3.7 V	12
Temperature under bias (ambient) Top		min -40 · max 85 °C	12
Load capacitance on digital ports Clop		max 20 pF	12
Maximum Input power ML	Sub-GHz path	max 0 dBm	12
Voltage Standing Wave Ratio VSWR	Sub-GHz and RFIO_HF path; maximum ratio 10:1	max 10 -	12
Human Body Model, JEDEC standard JESD22-A114, class II ESD_HBM		max 2 kV	13
ESD Charged Device Model, JEDEC standard JESD22-C101, class II ESD_CDM		max 500 V	13
Latch-up, JEDEC standard JESD78, class II level A LU		max 100 mA	13
Supply current in power down mode IDDPDN		typ 0.8 A	14
Supply current in SLEEP mode, no RTC IDDSL3	8kB RAM retained	typ 1.6 A	14
Supply current in SLEEP mode LFRC (32kHz) based RTC IDDSL1	No RAM retained	typ 1.6 A	14
Supply current in SLEEP mode LFRC (32kHz) based RTC IDDSL3A	8kB RAM retained	typ 1.85 A	14
Supply current in SLEEP mode LFXOSC (32kHz) based RTC IDDSL2	No RAM retained	typ 1.5 A	14
Supply current in SLEEP mode LFXOSC (32kHz) based RTC IDDSL4A	8kB RAM retained	typ 1.75 A	14
Supply current in STBY_RC IDDSBRLD	HFRC (32MHz) ON, LDO, System clock 16MHz	typ 1.25 mA	14
Supply current in STBY_XOSC IDDSBXLD	HFXOSC ON, LDO	typ 1.3 mA	14
Supply current in STBY_XOSC IDDSBXDC	HFXOSC ON, DC-DC	typ 1.1 mA	14
Supply current in Synthesizer mode IDDFSDC	DC-DC, system clock 32MHz	typ 2.85 mA	14
Supply current in Receive mode IDDRXF1	FSK 4.8kb/s sub-GHz	typ 5.4 mA	14
Supply current in Receive mode IDDRXF1	FSK 4.8kb/s sub-GHz with RxBoosted = 1	typ 7.5 mA	14
Supply current in Receive mode IDDRXF2	FSK 4.8kb/s 2.4GHz/S-band	typ 5.9 mA	14
Supply current in Receive mode IDDRXF2	FSK 4.8kb/s 2.4GHz/S-band with RxBoosted = 1	typ 6.6 mA	14
Supply current in Receive mode IDDRXL1	LoRa® SF12 125kHz sub-GHz	typ 5.7 mA	14
Supply current in Receive mode IDDRXL1	LoRa® SF12 125kHz sub-GHz with RxBoosted = 1	typ 7.8 mA	14
Supply current in Receive mode IDDRXL2	LoRa® SF12 125kHz 2.4GHz/S-band	typ 6 mA	14
Supply current in Receive mode IDDRXL2	LoRa® SF12 125kHz 2.4GHz/S-band with RxBoosted = 1	typ 6.7 mA	14
Supply current in Receive mode IDDRXL2	LoRa® SF12 406kHz 2.4GHz/S-band	typ 7.6 mA	14
Supply current in Receive mode IDDRXL2	LoRa® SF12 406kHz 2.4GHz/S-band with RxBoosted = 1	typ 8.3 mA	14
Supply current in Receive mode IDDRXL2	LoRa® SF12 812kHz 2.4GHz/S-band	typ 6.8 mA	14
Supply current in Receive mode IDDRXL2	LoRa® SF12 812kHz 2.4GHz/S-band with RxBoosted = 1	typ 7.5 mA	14
Transmit mode power consumption IDDTXLP1	868/915MHz; +14dBm, LP PA; output +15dBm; DC-DC supplies entire circuit	typ 36 mA	15
Transmit mode power consumption IDDTXLP2	868/915MHz; +14dBm, LP PA; output +14dBm; DC-DC supplies entire circuit	typ 28 mA	15
Transmit mode power consumption IDDTXLP3	868/915MHz; +14dBm, LP PA; output +10dBm; DC-DC supplies entire circuit	typ 18.5 mA	15
Transmit mode power consumption IDDTXLP4	434/490MHz; +14dBm, LP PA; output +15dBm; DC-DC supplies entire circuit	typ 35 mA	15
Transmit mode power consumption IDDTXLP5	434/490MHz; +14dBm, LP PA; output +14dBm; DC-DC supplies entire circuit	typ 28 mA	15
Transmit mode power consumption IDDTXLP6	434/490MHz; +14dBm, LP PA; output +10dBm; DC-DC supplies entire circuit	typ 19 mA	15
Transmit mode power consumption IDDTXHP1	868/915MHz; +22dBm, HP PA; output +22dBm; battery supplies PA, DC-DC supplies rest	typ 118 mA	15
Transmit mode power consumption IDDTXHP2	868/915MHz; +22dBm, HP PA; output +20dBm; battery supplies PA, DC-DC supplies rest	typ 96 mA	15
Transmit mode power consumption IDDTXHP3	868/915MHz; +22dBm, HP PA; output +17dBm; battery supplies PA, DC-DC supplies rest	typ 73 mA	15
Transmit mode power consumption IDDTXHP4	868/915MHz; +22dBm, HP PA; output +14dBm; battery supplies PA, DC-DC supplies rest	typ 50 mA	15
Transmit mode power consumption IDDTXHP5	434/490MHz; +22dBm, HP PA; output +22dBm; battery supplies PA, DC-DC supplies rest	typ 100 mA	15
Transmit mode power consumption IDDTXHP6	434/490MHz; +22dBm, HP PA; output +20dBm; battery supplies PA, DC-DC supplies rest	typ 86 mA	15
Transmit mode power consumption IDDTXHP7	434/490MHz; +22dBm, HP PA; output +17dBm; battery supplies PA, DC-DC supplies rest	typ 70 mA	15
Transmit mode power consumption IDDTXHP8	434/490MHz; +22dBm, HP PA; output +14dBm; battery supplies PA, DC-DC supplies rest	typ 45 mA	15
Transmit mode power consumption IDDTXHF1	2.4GHz; +13dBm, HF PA; output +13dBm	typ 26 mA	15
Transmit mode power consumption IDDTXHF2	2.4GHz; +13dBm, HF PA; output +10dBm	typ 23 mA	15
Transmit mode power consumption IDDTXHF3	S-band; +13dBm, HF PA; output +13dBm	typ 28 mA	15
Transmit mode power consumption IDDTXHF4	S-band; +13dBm, HF PA; output +10dBm	typ 24 mA	15
Maximum TX power TXOPLP	LP PA	min 12 · typ 15 dBm	21
Maximum TX power TXOPHP	HP PA	min 19 · typ 22 dBm	21
Drop in maximum TX power vs. VDD (1.8 to 3.7V) TXDRPLF1	LP PA operating under DC-DC or LDO	typ 0.5 dB	21
Drop in maximum TX power vs. VDD (1.8 to 3.7V) TXDRPLF2	HP PA, operating under battery	typ 6 dB	21
TX power range TXPRNGLF	Programmable in steps of -1dB from maximum TX power	typ 31 steps	21
TX output power step accuracy TXACCLF	Typical accuracy +/- 2 dB	typ 2 dB	21
Power amplifier ramping time TXRMPLF	Programmable, lowest step	typ 16 s	21
Power amplifier ramping time TXRMPLF	Programmable, highest step	typ 304 s	21
EVM for LR-FHSS TXEVM	GMSK 488b/s	max -20 dB	21
Maximum TX power TXOPHF	HF PA	min 9 · typ 11.5 dBm	21
Drop in maximum TX power vs. VDD (1.8 to 3.7V) TXDRPHF	LP PA operating under DC-DC or LDO	typ 0.5 dB	21
TX power range TXPRNGHF	Programmable in steps of -1dB from maximum TX power	typ 31 steps	21
TX output power step accuracy TXACCHF	Typical accuracy +/- 2 dB	typ 2 dB	21
EVM for LR-FHSS TXEVMHF	GMSK 488b/s	max -20 dB	21
Crystal oscillator frequency FXOSCHF		typ 32 MHz	22
Crystal loading capacitance CLOADHF	Differential	min 9.5 · typ 10 · max 10.5 pF	22
Crystal shunt capacitance C0XTALHF		min 0.3 · typ 0.6 · max 2 pF	22
Crystal series resistance RSXTALHF		typ 30 · max 60 	22
Crystal motional capacitance CMXTALHF		min 1.3 · typ 1.89 · max 2.5 fF	22
Drive level DRIVEHF		max 100 W	22
Crystal frequency accuracy FRTOLHF	Initial; +/- 10 ppm	max 10 ppm	22
Crystal frequency accuracy FRTOLHF	Over temperature (-20 to 70oC); +/- 10 ppm	max 10 ppm	22
Crystal frequency accuracy FRTOLHF	Aging over 10 years; +/- 10 ppm	max 10 ppm	22
External decoupling capacitor for REG_TCXO CVTCXO	X5R type recommended	min 70 · typ 100 · max 130 nF	22
Equivalent series resistance for CVTCXO RVTCXO		min 0.1 · max 1 Ohm	22
Regulated voltage range for TCXO voltage supply, VDDop > VTCXO + 200mV VTCXO	RegTcxoTune = 000	typ 1.6 V	22
Regulated voltage range for TCXO voltage supply, VDDop > VTCXO + 200mV VTCXO	RegTcxoTune = 001	typ 1.7 V	22
Regulated voltage range for TCXO voltage supply, VDDop > VTCXO + 200mV VTCXO	RegTcxoTune = 111	typ 3.3 V	22
Load current for TCXO regulator ILTCXO		typ 1.5 · max 4 mA	22
Amplitude voltage for external TCXO applied to XTA pin ATCXO	AC coupled through 10pF DC-cut series with 220Ohm	min 0.4 · typ 0.6 · max 1.2 Vpk-pk	22
Crystal oscillator frequency FXOSCLF		min 32400 · typ 32768 · max 33100 Hz	22
Crystal loading capacitance CLOADLF	Differential	typ 9 pF	22
Crystal shunt capacitance C0XTALLF		min 0.7 · typ 1.1 · max 2 pF	22
Crystal series resistance RSXTALLF		min 25 · typ 45 · max 100 k	22
Crystal motional capacitance CMXTALLF		min 1.5 · typ 4.7 · max 8 fF	22
Drive level DRIVELF		min 0.5 W	22
Crystal frequency accuracy FRTOLLF	Initial; +/-20 ppm	max 20 ppm	22
Crystal frequency accuracy FRTOLLF	Over temperature (-20 to 70°C); +/-180 ppm	max 180 ppm	22
Crystal frequency accuracy FRTOLLF	Aging over 10 years; +/-3 ppm	max 3 ppm	22
Theta j-a, Junction to Ambient	QFN32; measured on a 4-layer test board with 9 thermal vias, per the Jedec standard	typ 26.7 °C/W	32

Ordering codes, by the datasheet

LR1121IMLTRT: QFN32 · Tape & Reel; minimum order 3000 pieces · p. 2

Parameters

Applications: LoRa
Current - Supply: 5.7mA
Current - Supply(Max): 118mA
Current Of Transmitting: 26mA
Data Rate: 101.5Kbps
Features: Power-off reset function
Frequency Range: 1.9GHz~2.1GHz
Interface: SPI
Operating Temperature: -40℃~+85℃
Output Power: 13dBm
Receive Current: 7.8mA
Sensitivity: -108dBm
Standby Current: 800nA
Thermal Resistance(Junction to Ambient): 26.7℃/W
Type: transceiver
Typical Application Frequency: 2.4GHz
Voltage - Supply: 1.8V~3.7V
Voltage - Supply(Absolute Max): 3.9V

Order codes

LR1121IMLTRTLCSC C7498014

Pinout

The pins of the LR1121IMLTRT
Pin	Name	Type
1	VR_PA	Output
2	VBAT_RF	Input
3	VTCXO	Output
4	XTA	Passive
5	XTB	Passive
6	NRESET	Input
7	32k_P/_DIO11	Input/output
8	32k_P/_DIO10	Input/output
9	DIO9	Input/output
10	DIO8	Input/output
11	DIO7	Input/output
12	VREG	Output
13	GND	Power in
14	DCC_SW	Power in
15	VBAT	Input
16	DNC	Passive
17	DNC	Passive
18	DNC	Passive
19	DIO6	Input/output
20	DIO5	Input/output
21	DIO4	Input/output
22	DIO3	Input/output
23	DIO2	Input/output
24	DIO1	Input/output
25	DIO0/BUSY	Input/output
26	RFIO_HF	Input/output
27	DNC	Passive
28	DNC	Passive
29	RFI_N_FL0	Input
30	RFI_P_FL0	Input
31	RFO_LP_LF	Output
32	RFO_HP_LF	Output
33	GND	Power in

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Questions

Is there a KiCad symbol and footprint for the LR1121IMLTRT?

Yes. The symbol is Analog & Interface:LR1121IMLTRT and the footprint ICs And Semiconductors SMD:QFN50P500X500X100-33N-S380, both drawn on this page. PCBKit places them on a board for you when you design with it.

What package is the LR1121IMLTRT?

QFN-32-EP(5x5), with 33 pins. Its footprint is drawn on this page.

Where is the LR1121IMLTRT datasheet?

SEMTECH publishes it: the Datasheet link on this page opens it.

Where can I order the LR1121IMLTRT?

JLCPCB lists it as part C7498014, with 1,742 in stock; the sellers' links on this page open their listings.

Which open-source boards use the LR1121IMLTRT?

5 boards in 5 repositories on GitHub; the most starred are listed on this page, with their KiCad files.