LTM2893/LTM2895 SPI μModule® Isolators

Linear Technology’s 100 MHz SPI isolators facilitate fast data converters

Image of Linear Technology LTM2893/LTM2895 SPI μModule® Isolators (click for full-size)The LTM2893 and LTM2895 are high-speed, isolated μModule (micromodule) SPI interfaces from Linear Technology with ADC control signals. The LTM2893 is optimized for isolating 1-Msps, high-resolution, 18-bit SAR ADCs, such as the LTC2338 and similar families, and can interface with most general-purpose ADCs. The LTM2895 works with DACs and general-purpose DACs that have a mode (0, 0) SPI interface. The LTM2893-1 is optimized for isolating the LTC2348 and similar families of simultaneous sampling ADCs that require writing configuration settings into the ADC. The LTM2893 isolates the conversion start sampling signal with a very-low aperture jitter (30 ps) and low latency (20 ns).

The interface enables fast throughput with no cycle latency, which makes the LTM2893 and LTM2895 ideally suited for a wide variety of applications. The LTM2893 has a high-speed, SPI-compatible serial port that supports 1.71 V to 5.5 V logic and is configurable for ADCs with 8 to 32-bit SPI word lengths. It also isolates three select signals (SA, SB, SC) for controlling analog multiplexers or gain settings.

The isolation barrier tolerates large voltage ground variations between the logic interface and the isolated side of the LTM2893. Uninterrupted communication is maintained during voltage transients greater than 50 kV/μs.

Video: LTM2893 100 MHz Isolated SPI Analog-to-Digital Converter Solution

LTM2893 Features LTM2895 Features
  • Isolated interface: 6000 VRMS for 1 minute
  • UL-CSA recognition pending
  • 100 MHz SPI-compatible I/O
  • Configurable SPI word length 8 to 32 bits
  • Low jitter conversion start (30 psRMS)
  • Supports simultaneously sampled ADCs
  • Read only (LTM2893); read/write (LTM2893-1)
  • Three isolated multiplexer select signals
  • 1.71 V to 5.5 V I/O voltages
  • 3 V to 5.5 V supply voltages
  • High common mode transient immunity
  • 15 mm × 6.25 mm BGA package
  • Isolated interface: 6000 VRMS for 1 Minute
  • UL-CSA-IEC certification pending
  • 100 MHz SPI-compatible I/O
  • Configurable SPI word-length: 8 to 32 bits
  • Supports two isolated chip selects
  • Falling edge sensitive low jitter LOAD
  • Three isolated control or multiplexer signals
  • 1.71 V to 5.5 V I/O voltages
  • 3 V to 5.5 V supply voltages
  • High common mode transient immunity
  • 15 mm × 6.25 mm BGA package

Typical Application Diagram

Image of Linear Technology's LTM2893/95 Typical Application Diagram

LTM2893 SPI μModule Isolators

ImageManufacturer Part NumberDescriptionAvailable QuantityView Details
LTM2893IY-1#PBF datasheet linkDGTL ISO 6KV 10CH SPI 36BGALTM2893IY-1#PBFDGTL ISO 6KV 10CH SPI 36BGA160 - Immediate
LTM2893IY-1#PBF product page link
LTM2893IY#PBF datasheet linkDGTL ISO 6KV 9CH SPI 36BGALTM2893IY#PBFDGTL ISO 6KV 9CH SPI 36BGA145 - Immediate
LTM2893IY#PBF product page link
LTM2893CY-1#PBF datasheet linkDGTL ISO 6KV 10CH SPI 36BGALTM2893CY-1#PBFDGTL ISO 6KV 10CH SPI 36BGA160 - Immediate
LTM2893CY-1#PBF product page link
LTM2893CY#PBF datasheet linkDGTL ISO 6KV 9CH SPI 36BGALTM2893CY#PBFDGTL ISO 6KV 9CH SPI 36BGA152 - Immediate
LTM2893CY#PBF product page link
LTM2893HY-1#PBF datasheet linkDGTL ISO 6KV 10CH SPI 36BGALTM2893HY-1#PBFDGTL ISO 6KV 10CH SPI 36BGA160 - Immediate
LTM2893HY-1#PBF product page link
LTM2893HY#PBF datasheet linkDGTL ISO 6KV 9CH SPI 36BGALTM2893HY#PBFDGTL ISO 6KV 9CH SPI 36BGA158 - Immediate
LTM2893HY#PBF product page link

LTM2895 SPI μModule Isolators

ImageManufacturer Part NumberDescriptionAvailable QuantityView Details
LTM2895IY#PBF datasheet linkDGTL ISO 100MHZ SPI 36BGALTM2895IY#PBFDGTL ISO 100MHZ SPI 36BGA139 - Immediate
LTM2895IY#PBF product page link
LTM2895HY#PBF datasheet linkDGTL ISO 100MHZ SPI 36BGALTM2895HY#PBFDGTL ISO 100MHZ SPI 36BGA160 - Immediate
LTM2895HY#PBF product page link
LTM2895CY#PBF datasheet linkDGTL ISO 100MHZ SPI 36BGALTM2895CY#PBFDGTL ISO 100MHZ SPI 36BGA80 - Immediate
LTM2895CY#PBF product page link

Demonstration Board

ImageManufacturer Part NumberDescriptionAvailable QuantityView Details
DC2405A datasheet linkDEMO BOARD FOR LTM2893DC2405ADEMO BOARD FOR LTM28935 - Immediate
DC2405A product page link
Published: 2017-03-22