SP491EEP-L Equivalent & Substitute Parts

Part Overview

The SP491EEP-L is a 1/1 full-duplex RS422/RS485 transceiver manufactured by MaxLinear, Inc., housed in a 14-pin DIP package for through-hole mounting. This part is classified as obsolete, making equivalent and substitute components necessary for ongoing system support, maintenance, and new design implementations. The SP491EEP-L operates across industrial temperature ranges and is suitable for serial communication applications requiring robust noise immunity and full-duplex capability.

Key Parameters

Parameter	Value
Manufacturer Part Number	SP491EEP-L
Manufacturer	MaxLinear, Inc.
Type	Transceiver
Protocol	RS422, RS485
Number of Drivers/Receivers	1/1
Duplex	Full
Receiver Hysteresis	70 mV
Data Rate	10 Mbps
Voltage - Supply	4.75V ~ 5.25V
Operating Temperature	-40°C ~ 85°C
Mounting Type	Through Hole
Package / Case	14-DIP (0.300", 7.62mm)
Supplier Device Package	14-PDIP
Moisture Sensitivity Level (MSL)	1 (Unlimited)
Product Status	Obsolete

Substitute Part Grouping Explanation

Substitution of the SP491EEP-L is determined by strict adherence to the following electrical and mechanical parameters:

Critical Matching Parameters:

Protocol: RS422/RS485 full-duplex operation
Number of Drivers/Receivers: 1/1 configuration
Duplex Mode: Full-duplex capability
Supply Voltage Range: 4.75V ~ 5.25V
Package Type: 14-DIP through-hole mounting
Mounting Type: Through Hole

Acceptable Variation Parameters:

Receiver Hysteresis: 20 mV to 70 mV (affects noise immunity threshold)
Data Rate: 250 kbps minimum to 30 Mbps maximum (backward compatible if equal or higher)
Operating Temperature: Must encompass or match the -40°C ~ 85°C range
Moisture Sensitivity Level: MSL 1 or MSL 2 acceptable for through-hole packages

Substitute parts are grouped into two categories: direct pin-compatible replacements maintaining identical electrical performance characteristics, and functionally equivalent alternatives with modified specifications that remain suitable for RS422/RS485 serial communication applications.

Parameter Comparison

Part Number	Manufacturer	Protocol	Drivers/Receivers	Duplex	Hysteresis (mV)	Data Rate	Supply Voltage	Temp Range (°C)	Package	Mounting	Status
SP491EEP-L	MaxLinear, Inc.	RS422, RS485	1/1	Full	70	10 Mbps	4.75V ~ 5.25V	-40 ~ 85	14-DIP	Through Hole	Obsolete
SP491EN-L/TR	MaxLinear, Inc.	RS422, RS485	1/1	Full	70	5 Mbps	4.75V ~ 5.25V	-40 ~ 85	14-SOIC	Surface Mount	Active
LT1791ACN#PBF	Analog Devices Inc.	RS422, RS485	1/1	Full	20	250 kbps	4.75V ~ 5.25V	0 ~ 70	14-DIP	Through Hole	Active
LT1791HN#PBF	Analog Devices Inc.	RS422, RS485	1/1	Full	20	250 kbps	4.75V ~ 5.25V	-40 ~ 125	14-DIP	Through Hole	Active
LTC491CN#PBF	Analog Devices Inc.	RS422, RS485	1/1	Full	70	—	4.75V ~ 5.25V	0 ~ 70	14-DIP	Through Hole	Active
LTC491IN#PBF	Analog Devices Inc.	RS422, RS485	1/1	Full	70	—	4.75V ~ 5.25V	-40 ~ 85	14-DIP	Through Hole	Active
MAX491CPD+	Analog Devices Inc./Maxim Integrated	RS422, RS485	1/1	Full	70	2.5 Mbps	4.75V ~ 5.25V	0 ~ 70	14-DIP	Through Hole	Active
MAX491ECPD+	Analog Devices Inc./Maxim Integrated	RS422, RS485	1/1	Full	70	2.5 Mbps	4.75V ~ 5.25V	0 ~ 70	14-DIP	Through Hole	Active
MAX491EEPD+	Analog Devices Inc./Maxim Integrated	RS422, RS485	1/1	Full	70	2.5 Mbps	4.75V ~ 5.25V	-40 ~ 85	14-DIP	Through Hole	Active
MAX491EPD+	Analog Devices Inc./Maxim Integrated	RS422, RS485	1/1	Full	70	2.5 Mbps	4.75V ~ 5.25V	-40 ~ 85	14-DIP	Through Hole	Active
SN65LBC180AN	Texas Instruments	RS422, RS485	1/1	Full	50	30 Mbps	4.75V ~ 5.25V	-40 ~ 85	14-DIP	Through Hole	Obsolete

Engineering Selection Recommendations

Primary Substitutes (Highest Compatibility):

LTC491IN#PBF and MAX491EEPD+ are the preferred substitutes for the SP491EEP-L. Both maintain identical operating temperature range (-40°C ~ 85°C), matching receiver hysteresis (70 mV), 14-DIP through-hole package configuration, and full-duplex RS422/RS485 protocol support. LTC491IN#PBF is manufactured by Analog Devices Inc. with ROHS3 compliance and unlimited moisture sensitivity rating. MAX491EEPD+ is manufactured by Analog Devices Inc./Maxim Integrated with ROHS3 compliance. Both parts are in active production status, ensuring long-term availability.

Secondary Substitutes (Extended Temperature Range):

LT1791HN#PBF extends the operating temperature range to -40°C ~ 125°C, providing enhanced thermal performance for applications requiring operation beyond standard industrial limits. This part maintains the 14-DIP through-hole package and full-duplex RS422/RS485 configuration. The receiver hysteresis is reduced to 20 mV, which may be suitable for applications with lower noise environments. Data rate is specified at 250 kbps, which is lower than the original part but remains functional for serial communication applications.

Alternative Substitutes (Commercial Temperature Range):

MAX491CPD+ and MAX491ECPD+ operate within the commercial temperature range (0°C ~ 70°C) and are suitable for applications not requiring extended low-temperature operation. Both maintain 70 mV receiver hysteresis, 14-DIP through-hole packaging, and 2.5 Mbps data rate capability. These parts are in active production with ROHS3 compliance.

Compliance Status:

All recommended substitute parts carry ROHS3 compliance certification. The SP491EEP-L is classified as obsolete; therefore, transition to active production parts is necessary for new designs and long-term system support. LTC491IN#PBF, MAX491EEPD+, and MAX491EPD+ are recommended for designs requiring extended temperature operation matching the original specification.

Frequently Asked Questions (FAQ)

Q: Can SP491EN-L/TR replace SP491EEP-L in existing through-hole designs?

A: No. SP491EN-L/TR uses a 14-SOIC surface-mount package, which is incompatible with through-hole PCB layouts designed for 14-DIP components. The SP491EN-L/TR is suitable only for new designs utilizing surface-mount assembly processes.

Q: What is the difference between LTC491IN#PBF and LTC491CN#PBF?

A: Both parts maintain identical electrical specifications including 70 mV receiver hysteresis and 14-DIP through-hole packaging. The primary difference is operating temperature range: LTC491IN#PBF operates from -40°C ~ 85°C, matching the original SP491EEP-L specification, while LTC491CN#PBF operates from 0°C ~ 70°C, limiting use in extended low-temperature applications.

Q: Are MAX491 series parts pin-compatible with SP491EEP-L?

A: Yes. MAX491CPD+, MAX491ECPD+, MAX491EEPD+, and MAX491EPD+ all use 14-DIP through-hole packaging with identical pin configuration. Electrical compatibility is maintained for RS422/RS485 full-duplex operation. Data rate is reduced to 2.5 Mbps compared to the original 10 Mbps specification, but this remains suitable for standard serial communication applications.

Q: Which substitute part has the highest data rate capability?

A: SN65LBC180AN, manufactured by Texas Instruments, supports 30 Mbps data rate, exceeding the original SP491EEP-L specification of 10 Mbps. This part is classified as obsolete but remains available in inventory. It maintains 14-DIP through-hole packaging and -40°C ~ 85°C operating temperature range with 50 mV receiver hysteresis.

Q: What is the significance of receiver hysteresis in RS422/RS485 transceiver selection?

A: Receiver hysteresis determines the voltage differential required to switch receiver output states, affecting noise immunity. The SP491EEP-L specifies 70 mV hysteresis. Substitute parts with lower hysteresis (20 mV) provide faster switching response but reduced noise immunity in electrically noisy environments. Substitute parts with matching 70 mV hysteresis maintain equivalent noise performance.

Q: Can LT1791 series parts operate at the full -40°C ~ 85°C range?

A: LT1791HN#PBF operates from -40°C ~ 125°C, exceeding the original specification. LT1791ACN#PBF operates from 0°C ~ 70°C, which does not cover the full low-temperature range of the original part. For applications requiring -40°C operation, LT1791HN#PBF is the appropriate LT1791 variant.

Q: Is moisture sensitivity level (MSL) a critical factor in substitute selection?

A: For through-hole mounted components, MSL is less critical than for surface-mount packages. The SP491EEP-L specifies MSL 1 (Unlimited). Substitute parts with MSL 1 or MSL 2 are acceptable for through-hole applications. MSL becomes significant only when extended storage periods exceed manufacturer specifications.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message