DC1682B Datasheet, PDF (7/26 Pages) Linear Dimensions Semiconductor – 12-port Type 2 power sourcing equipment (PSE) composed of a DC1682B daughter card and DC1680A mother board.

DEMO MANUAL DC1840B
Demonstration Circuit 1682B Operation
I²C Communication and Addressing
The LTC4271 internal registers are accessed via I²C to read
and/or write configuration, status, and interrupt registers.
The I²C lines SDAOUT, SDAIN and SCL connect to the
34-pin connector (Figure 7). Subsequently, the I²C bus
is accessed on the DC1680.
The LTC4270/LTC4271 chipset has an address of
(A₆10A₃A₂A₁A₀b), where A₆, A₃, A₂, A₁, and A₀ are the
logic state of the AD6, AD3, AD2, AD1, and AD0 pins
respectively. On the DC1682B, AD0 and AD1 are tied low
with pull-down resistors. AD2, AD3 and AD6 are brought
out to the 34-pin connector (Figure 7) and set with three
switches on the DC1680.
J2, PIN 9
J2, PIN 10
R30
27k
D4
GRN
XIO1
Q13A
BC846AS
R32
220k
R31
27k
D5
GRN
XIO0
Q13B
BC846AS
R33
220k
AGND
LTC4270
XIO1
XIO0
V_EE
V_EE
DC1840B F08
Figure 8. DC1682B, LTC4270 General Purpose I/O LED Indicators
R7
0Ω
SDAOUT
SDAIN
SCL
INT
LTC4271
AD6
AD3
AD2
AD1
AD0
DGND
SDAOUT
SDAIN
SCL
INT
TO 34-PIN
CONNECTOR
AD6
AD3
AD2
R8 R9
0Ω 0Ω
DC1840B F07
Figure 7. DC1682B LTC4271 I²C and Address Connections
V_DD33
LTC4271
GP1
GP0
DGND
DC1840B F09
R28
560Ω
D2
GRN
GP1
R29
560Ω
D3
GRN
GP0
J2, PIN 5
J2, PIN 6
Figure 9. DC1682B, LTC4271 General Purpose I/O LED Indicators
I/O LED Indicators
The DC1682B features four LEDs to indicate the states of
the LTC4270/LTC4271 chipset general purpose input output
pins. These pins are configured as inputs or outputs via
I²C. GP1 and GP0 are referenced to DGND and driven by
the LTC4271 when set as outputs (Figure 8). XIO0 and
XIO1 are referenced to V_EE and are driven by the LTC4270
when set as outputs (Figure 9). J2 provides test points
for access to these I/Os.
V_DD33
V_DD33
LTC4271
JP1 _AUTO JP2 _MID
HI
HI
LO
LO
AUTO
MID
DGND
DC1840B F10
J2, PIN 3
J2, PIN 4
Figure 10. DC1682B AUTO and MID Jumpers
dc1840bfc
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