DS1875T+ Maxim Integrated Products, DS1875T+ Datasheet - Page 65

• Manufacturer Part Number: DS1875T+
• Description: IC SFP CTRLR/TRIPLEXER 38-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of DS1875T+

• Applications: Fiber Optics
• Interface: I²C
• Voltage - Supply: 2.85 V ~ 3.9 V
• Package / Case: *
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 02h, Register 88h: SAMPLE RATE
88h
Defines the sample rate for comparison of APC control.
FACTORY DEFAULT
READ ACCESS
WRITE ACCESS
MEMORY TYPE
BITS 7:6
BITS 5:4
BITS 3:0
BIT 7
SEE
______________________________________________________________________________________
* All codes greater than 1001b (1010b to 1111b) use the maximum sample time of
code 1001b.
SEE
PWM_FR[1:0]: 2-bit frequency rate for the SW pulsed output used with PWM. When switching a
lower to a higher frequency, disable the SW output by setting SOFT M3QT (Byte 78h) to a 1 before
changing PWM_FR. After changing PWM_FR, wait 200 periods of the new frequency before
enabling the SW output. This delay allows for the internal signals to integrate and lock to the new
frequency without creating a large duty cycle.
00b: 131.25kHz
01b: 262.5kHz
10b: 525kHz
11b: 1050kHz (Default)
APC_SR[3:0]: 4-bit sample rate for comparison of APC control.
APC_SR[3:0]
SEE
1001b*
0000b
0001b
0010b
0011b
0100b
0101b
0110b
0111b
1000b
PON Triplexer and SFP Controller
30h
PW2
PW2
Nonvolatile (SEE)
PWM_FR
1
BEN TO FIRST SAMPLE
MINIMUM TIME FROM
PWM_FR
(t
FIRST
1350
1550
1750
2150
2950
3150
(ns)
350
550
750
950
) ±50ns
0
APC_SR
3
FIRST SAMPLE (t
REPEATED SAMPLE
PERIOD FOLLOWING
APC_SR
1200
1600
2000
2800
3200
3600
4400
6000
6400
(ns)
800
2
REP
APC_SR
)
1
APC_SR
BIT 0
0
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