LTM2895
100MHz Isolated
DAC SPI Serial Interface
FEATURES DESCRIPTION
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Isolated Interface: 6000V for 1 Minute The LTM 2895 is a high speed isolated Module (micro-
RMS
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CSA (IEC/UL) Approved, File #255632 module) SPI interface with DAC control signals designed
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to isolate LTCs family of general purpose DACs and to
100MHz SPI-Compatible I/O
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isolate general purpose SPI interfaces. The LTM2895
Configurable SPI Word-Length: 8 to 32 Bits
n works with DACs and general purpose devices that have
Supports Two Isolated Chip Selects
n a mode (0, 0) SPI interface.
Falling Edge Sensitive Low Jitter LOAD
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Three Isolated Control or Multiplexer Signals
The interface enables fast data throughput, which makes
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1.71V to 5.5V I/O Voltages
the LTM2895 ideally suited for a wide variety of applica-
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3V to 5.5V Supply Voltages
tions. The high speed SPI-compatible serial port supports
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High Common Mode Transient Immunity
1.71V to 5.5V logic supplies. The LTM2895 is targeted at
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15mm 6.25mm BGA Package
generic SPI and digital-to-analog converter applications.
The isolation barrier tolerates large voltage ground varia-
APPLICATIONS
tions between the logic interface and the isolated side of
the LTM2895. Uninterrupted communication is maintained
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Remote Interface Control
during voltage transients greater than 50kV/s.
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Industrial Process Control and Automation
All registered trademarks and trademarks are the property of their respective owners.
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Test and Measurement Equipment
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Breaking Ground Loops
TYPICAL APPLICATION
LTC2642-16 DAC Isolation
LT6654-5
8V V V
3.3V 5V i IN OUT
i
GND
10F
10k
V V V V V 5V
DD L CC CC2 L2 i
ON ON ON2
SYSINT BUSY V REF
LTM2895 DD
100k
FLTINT FAULT
27pF
RFB
LOAD LOAD LOAD2
8V
i
CS
CS SS SS2
P
I
NV
CS2 SSB SSB2
SCK SCK SCK2 SCK
LT1468 OUT
LTC2642-16
MOSI MOSI MOSI2
D
+
IN
V
MISO MISO MISO2 OUT
SA SA2 CLR
CLR
8V
i
SB SB2
SC SC2
GND
GND GND GND2
2895TA01
CONFIGURATION REGISTERS: WRITE 0x30H AND 0x83H
SETS SCK2 TO 33MHz AND WORDLENGTH TO 16-BIT
V = ISOLATED VOLTAGE SUPPLY
i
2895fa
1
For more information www.linear.com/LTM2895
ISOLATION BARRIERLTM2895
ABSOLUTE MAXIMUM RATINGS (Note 1)
Supply Voltages Isolated Signals
V GND .................................................0.3V to 6V SS2, SSB2, MISO2, ON2, LOAD2, SCK2
L
V GND ...............................................0.3V to 6V SA2, SB2, SC2, MOSI2 .....GND2 0.3V to V + 0.3V
CC L2
Isolated Supply Voltages Operating Temperature Range (Note 10)
V GND2 .............................................0.3V to 6V LTM2895C ............................................... 0C to 70C
L2
V GND2 ............................................0.3V to 6V LTM2895I ............................................40C to 85C
CC2
Logic Signals LTM2895H .........................................40C to 125C
ON, LOAD, BUSY, SA, SB, SC, SS, SSB Storage Temperature Range .................. 55C to 125C
SCK, MOSI, MISO ................ GND 0.3V to V + 0.3V Maximum Internal Operating Temperature ............ 125C
L
FAULT ............................................... GND 0.3V to 6.3V Peak Body Reflow Temperature ............................260C
PIN CONFIGURATION
TOP VIEW
6
LOAD FAULT SC SC2 DNC LOAD2
5
BUSY GND SB SB2 GND2 DNC
4
SCK SSB SA SA2 SSB2 SCK2
3
MOSI GND GND GND2 GND2 MOSI2
2
SS MISO GND GND2 MISO2 SS2
1
ON V V V V ON2
L CC CC2 L2
A B C D E F G H J K L M N P R
BGA PACKAGE
36-LEAD (15mm 6.25mm 2.06mm)
T = 125C, = 36C/W, = 27.5C/W, = 17.5C/W
JMAX JA JCTOP JCBOTTOM
= 19.1C/W, WEIGHT = 0.36g
JB
ORDER INFORMATION