ds1865 Maxim Integrated Products, Inc., ds1865 Datasheet
ds1865
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ds1865 Summary of contents
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... Rev 0; 3/07 General Description The DS1865 controls and monitors all the burst-mode transmitter and video receiver biasing functions for a passive optical network (PON) triplexer. It has an APC loop with tracking-error compensation that provides the reference for the laser driver bias current and a temper- ature-indexed lookup table (LUT) that controls the mod- ulation current ...
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PON Triplexer Control and Monitoring Circuit ABSOLUTE MAXIMUM RATINGS Voltage Range on MON1–MON4, BEN, BMD, and TX-D Pins Relative to Ground.................-0. (subject to not exceeding +6V) Voltage Range SDA, SCL, D0–D3, and CC TX-F Pins ...
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ELECTRICAL CHARACTERISTICS (DAC1 and M4DAC +2.85V to +5.5V -40°C to +95°C, unless otherwise noted PARAMETER DAC Output Range DAC Output Resolution DAC Output Integral Nonlinearity DAC Output Differential Nonlinearity DAC Error DAC Temperature ...
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PON Triplexer Control and Monitoring Circuit ANALOG VOLTAGE MONITORING (V = 2.85V to 5.5V -40°C to +95°C, unless otherwise noted PARAMETER SYMBOL ∆VMON Input Resolution ∆V Supply Resolution Input/Supply Accuracy ( ...
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... Note 6: Eight ranges allow the BMD full-scale range to change from 312.5mV to 1.25V. Note 7: The output impedance of the DS1865 is proportional to its scale setting. For instance, if using the 1/2 scale, the output impedance would be approximately 1.56kΩ. Note 8: This specification applies to the expected full-scale value for the selected range. See the Mod Ranging byte for available full-scale ranges ...
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PON Triplexer Control and Monitoring Circuit 3.3V +25°C, unless otherwise noted SUPPLY CURRENT vs. SUPPLY VOLTAGE 7.000 SDA = SCL = V CC 6.500 6.000 +95°C 5.500 5.000 4.500 +25°C -40°C 4.000 3.500 ...
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3.3V +25°C, unless otherwise noted MON1–MON4 INL 1.0 USING FACTORY-PROGRAMMED 0.8 FULL-SCALE VALUE OF 2.5V 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 0 0.5 MON1–MON4 INPUT VOLTAGE (V) V BMD 1.0 ...
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PON Triplexer Control and Monitoring Circuit PIN NAME 1 BEN Burst Enable Input. Triggers the sampling of the APC and quick-trip monitors. 2 TX-D Transmit Disable Input. Disables BIAS and MOD outputs. 3 TX-F Transmit Fault Output, Open Drain 4 ...
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... V CC DS1865 MEMORY ORGANIZATION V CC SDA INTERFACE SCL ALARM/WARNING COMPARISON RESULTS/THRESHOLDS TABLE 01h (EEPROM) EEPROM PW1 USER MEMORY, ALARM TRAP 128 BYTES AT TABLE 02h (EEPROM) A0h SLAVE CONFIGURATION AND CALIBRATION ADDRESS V TABLE 03h (EEPROM) CC PW2 USER MEMORY MON1 MON2 13-BIT ...
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... CMOS process, while leaving only the high-speed portions to the laser driver. Key components of the DS1865 are shown in the Block Diagram and described in subsequent sections. Table 1 contains a list of acronyms used in this data sheet. ...
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... This allows the application to take full advantage of the APC reference’s resolution. The DS1865 has an LUT to allow the APC set point to change as a function of temperature to compensate for tracking error (TE). The TE LUT (Table 05h) has 36 entries that determine the APC setting in 4° ...
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... APC set point. Depending on the results of the comparison, the corresponding alarms and warnings (TXP-HI, TXP-LO) are asserted or deasserted. The DS1865 has a programmable comparator sample time based on an internally generated clock to facilitate a wide variety of external filtering options suitable for burst-mode transmitter data rates between 155Mbps and 1250Mbps ...
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... I exceed the value set in the MAX IBIAS register. When the DS1865 detects that the bias is at the limit, it sets the BIAS MAX status bit and holds the bias current at the MAX IBIAS level. The quick-trips are routed to the TX-F ...
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... If the FETG output triggers, indicating that the DS1865 is in shutdown, it requires TX-D, soft TX-D, or cycling power to be reset. Under all conditions, when the analog outputs are reinitialized after being disabled, all the alarms with the exception of the V are cleared ...
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... I up, the ATB is zeros until alarms dictate otherwise The DS1865 has an ID hard coded to its die. Two regis- ters (Table 02h bytes 86h–87h) are assigned for this low alarm, the CC feature. Byte 86h reads 65h to identify the part as the DS1865, byte 87h reads the die revision ...
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... Register 8Ch), the default device address is A2h until V exceeds recalled from the EEPROM. MOD AND BIAS OUTPUTS POA holds the DS1865 in reset until V Enabled level (V CC Disabled with its ADC and compare analog signals with its quick- trip monitors. Because V Disabled ...
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... TO 0 Digital I/O Pins allows the outputs to be used to control serial interfaces without wearing out the default EEPROM setting. The DS1865 features eight banks of memory composed of the following. The Lower Memory is addressed from 00h to 7Fh and contains alarm and warning thresholds, flags, masks, several control registers, password entry area (PWE), and the table select byte ...
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... EEPROM. Shadowed EEPROM (SEE) can be configured as either volatile or nonvolatile memory using the SEEB bit in Table 02h, Register 80h. The DS1865 uses shadowed EEPROM memory for key memory addresses that can be rewritten many times. By default the shadowed EEPROM bit, SEEB, is not set and these locations act as ordinary EEPROM ...
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... R the master indicates it will write data to the slave the mas- ter reads data from the slave incorrect slave address is written, the DS1865 assumes the master is communicat- ing with another I tions until the next START condition is sent. ...
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... START condi- tion, writes the slave address byte (R/W = 0), writes the memory address, writes data bytes, and gener- ates a STOP condition. The DS1865 writes bytes (1 page or row) with a single write transaction. This is internally controlled by an address counter that allows ...
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Reading a Single Byte from a Slave: Unlike the write operation that uses the memory address byte to define where the data written, the read operation occurs at the present value of the memory address counter. To ...
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... DIN RESERVED PWE MSB <2> <3> <4> <5> <6> All All PW2 All N and PW2 + DS1865 N/A All mode bit har dwar e Register Maps WORD 2 WORD 3 BYTE 4/C BYTE 5/D BYTE 6/E TEMP WARN HI TEMP WARN WARN WARN LO MON1 WARN HI MON1 WARN LO MON2 WARN HI ...
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... ALARM 2 ALARM 1 ALARM 0 <2> <3> <4> <5> All All PW2 All Al l and PW2 + DS1865 N/A All mode bit har dwar e ____________________________________________________________________ Monitoring Circuit WORD 2 WORD 3 BYTE 4/C BYTE 5/D BYTE 6 ...
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... TX TX RESERVED RESERVED EMPTY EMPTY EMPTY <4> <10> <10> NTL BIAS DAC 1 <2> <3> <4> <5> All All PW2 All Al l and PW2 + DS1865 N/A All mode bit har dwar e WORD 2 WORD 3 BYTE 4/C BYTE 5/D BYTE 6/E <4> <10> <10> V INDEX M4DAC DEVICE COMP RSHIFT 1 RANGING MON1 SCALE MON2 SCALE ...
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... <2> <3> <4> <5> All All PW2 All Al l and PW2 + DS1865 N/A All mode bit har dwar e ____________________________________________________________________ Monitoring Circuit WORD 2 WORD 3 BYTE 4/C BYTE 5/D BYTE 6 ...
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... APC REF APC REF APC REF APC REF APC REF APC REF APC REF <2> <3> <4> <5> <6> All All PW2 All N and PW2 + DS1865 N/A All mode bit har dwar e WORD 2 WORD 3 BYTE 4/C BYTE 5/D BYTE 6/E MOD MOD MOD MOD MOD MOD MOD MOD MOD ...
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... M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC <2> <3> <4> <5> All All PW2 All Al l and PW2 + DS1865 N/A All mode bit har dwar e ____________________________________________________________________ Monitoring Circuit WORD 2 WORD 3 BYTE 4/C BYTE 5/D BYTE 6/E M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC M4DAC ...
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... <2> <3> <4> <5> <6> All All PW2 All N and PW2 + DS1865 N/A All mode bit har dwar e WORD 2 WORD 3 BYTE 4/C BYTE 5/D BYTE 6 ...
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Lower Memory, Register 00h to 01h: Temp Alarm Hi Lower Memory, Register 04h to 05h: Temp Warn Hi FACTORY DEFAULT: 7FFFh READ ACCESS All WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) 6 00h, 04h 01h, 05h ...
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PON Triplexer Control and Monitoring Circuit Lower Memory, Register 08h to 09h: V Lower Memory, Register 0Ch to 0dh: V Lower Memory, Register 10h to 11h: MON1 Alarm Hi Lower Memory, Register 14h to 15h: MON1 Warn Hi Lower Memory, ...
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Lower Memory, Register 0Ah to 0Bh: V Lower Memory, Register 0Eh to 0Fh: V Lower Memory, Register 12h to 13h: MON1 Alarm Lo Lower Memory, Register 16h to 17h: MON1 Warn Lo Lower Memory, Register 1Ah to 1Bh: MON2 Alarm ...
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PON Triplexer Control and Monitoring Circuit Lower Memory, Register 60h to 61h: Temp Value POWER-ON VALUE 0000h READ ACCESS All WRITE ACCESS N/A MEMORY TYPE: Volatile 6 60h 61h 2 2 bit7 Signed two’s complement direct-to-temperature ...
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Lower Memory, Register 6Eh: Status POWER-ON VALUE x000 0x0x b READ ACCESS All WRITE ACCESS See Below MEMORY TYPE: Volatile Access N/A ALL FETG SOFT 6Eh STATUS FETG bit7 FETG STATUS: Reflects the active state of ...
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... PON Triplexer Control and Monitoring Circuit Lower Memory, Register 6Fh: Update POWER-ON VALUE 00h READ ACCESS All WRITE ACCESS All + DS1865 Hardware MEMORY TYPE: Volatile 6Fh TEMP RDY V RDY CC bit7 Update of completed conversions. At power-on, these bits are cleared and are set as each conversion is completed. ...
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Lower Memory, Register 70h: Alarm 3 POWER-ON VALUE 10h READ ACCESS All WRITE ACCESS N/A MEMORY TYPE: Volatile 70h TEMP HI TEMP LO bit7 TEMP HI: High Alarm Status for Temperature Measurement (Default) Last measurement was equal to ...
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PON Triplexer Control and Monitoring Circuit Lower Memory, Register 71h: Alarm 2 POWER-ON VALUE 00h READ ACCESS All WRITE ACCESS N/A MEMORY TYPE: Volatile 71h MON3 HI MON3 LO bit7 MON3 HI: High Alarm Status for MON3 Measurement ...
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Lower Memory, Register 73h: Alarm 0 POWER-ON VALUE 00h READ ACCESS All WRITE ACCESS N/A MEMORY TYPE: Volatile 73h RESERVED RESERVED bit7 bit7:4 RESERVED BIAS MAX: Alarm Status for Maximum Digital Setting of I bit3 0 = (Default) The value ...
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PON Triplexer Control and Monitoring Circuit Lower Memory, Register 74h: Warn 3 POWER-ON VALUE 10h READ ACCESS All WRITE ACCESS N/A MEMORY TYPE: Volatile 74h TEMP HI TEMP LO bit7 TEMP HI: High Warning Status for Temperature Measurement ...
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Lower Memory, Register 75h: Warn 2 POWER-ON VALUE 00h READ ACCESS All WRITE ACCESS N/A MEMORY TYPE: Volatile 75h MON3 HI MON3 LO bit7 MON3 HI: High Warning Status for MON3 Measurement (Default) Last measurement was equal to ...
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PON Triplexer Control and Monitoring Circuit Lower Memory, Register 78h: DOUT POWER-ON VALUE Recalled from Table 02h, Register C0h READ ACCESS All WRITE ACCESS All MEMORY TYPE: Volatile 78h RESERVED RESERVED bit7 At power-on, these bits are defined by the ...
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... Password Entry. There are two passwords for the DS1865. Each password is 4 bytes long. The lower level password (PW1) will have access to all unprotected areas plus those made available with PW1. The higher level password (PW2) will have all the access of PW1 plus those made available with PW2 ...
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PON Triplexer Control and Monitoring Circuit Table 01h, Register 80h to F7h: PW1 EEPROM POWER-ON VALUE 00h READ ACCESS PW1 WRITE ACCESS PW1 MEMORY TYPE Nonvolatile (EE) 80h-F7h EE EE bit7 EEPROM for PW1 level access. Table 01h, Register F8h: ...
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Table 01h, Register FAh: Alarm 1 POWER-ON VALUE 00h READ ACCESS All WRITE ACCESS PW1 MEMORY TYPE: Volatile FAh RESERVED RESERVED bit7 Layout is identical to Alarm 1 1. These bits are latched. They are cleared by power-down or a ...
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PON Triplexer Control and Monitoring Circuit Table 01h, Register FDh: Warn 2 POWER-ON VALUE 00h READ ACCESS All WRITE ACCESS PW1 MEMORY TYPE: Volatile FDh MON3 HI MON3 LO bit7 Layout is identical to Warn 2 1. These bits are ...
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Table 02h, Register 80h: Mode POWER-ON VALUE 1Fh READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Volatile 80h SEEB RESERVED bit7 SEEB (Default) Enables EEPROM writes to SEE bytes. bit7 1 = Disables EEPROM writes to SEE bytes ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register 81h: Tindex POWER-ON VALUE 00h READ ACCESS PW2 WRITE ACCESS PW2 and (AEN = 0) MEMORY TYPE Volatile 7 6 81h 2 2 bit7 Holds the calculated index based on the ...
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Table 02h, Register 84h: Vindex FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 and (AEN = 0) MEMORY TYPE Volatile 7 6 84h 2 2 bit7 Holds the calculated index based on the MON4 voltage measurement. This index is ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register 87h: Device VER FACTORY DEFAULT Device Version READ ACCESS PW2 WRITE ACCESS N/A MEMORY TYPE ROM 87h bit7 Hardwired connections to show device version. Table 02h, Register 88h: Update Rate FACTORY ...
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Table 02h, Register 89h: Config FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) 89h FETG DIR TX-F EN bit7 Configure the memory location and the polarity of the digital outputs. FETG DIR: Chooses the direction ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register 8Bh: MOD Ranging FACTORY DEFAULT: 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) 8Bh RESERVED RESERVED bit7 The lower nibble of this byte controls the full-scale range of ...
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Table 02h, Register 8Dh: Comp Ranging FACTORY DEFAULT: 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) 8Dh RESERVED BIAS 2 bit7 The upper nibble of this byte controls the Full-Scale range of the Quick-Trip monitoring for BIAS. ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register 8Eh: Right Shift 1 FACTORY DEFAULT: 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) 8Eh RESERVED MON1 2 bit7 Allows for right-shifting the final answer of MON1 and ...
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Table 02h, Register 92h to 93h: V Scale CC Table 02h, Register 94h to 95h: MON1 Scale Table 02h, Register 96h to 97h: MON2 Scale Table 02h, Register 98h to 99h: MON3 Scale Table 02h, Register 9Ah to 9Bh: MON4 ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register ACh to ADh: Reserved FACTORY DEFAULT: 0000 0000h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) These registers are reserved. Table 02h, Register AEh to AFh: Internal Temp Offset ...
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Table 02h, Register B4h to B7h: PW2 FACTORY DEFAULT FFFF FFFFh READ ACCESS N/A WRITE ACCESS PW2 MEMORY TYPE Nonvolatile (SEE B4h B5h B6h B7h 2 ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register B8h: FETG Enable FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) B8h TEMP bit7 Configures the maskable interrupt for the FETG pin. ...
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Table 02h, Register B9h: FETG Enable FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) B9h HTXP EN LTXP EN bit7 Configures the maskable interrupt for the FETG pin. HTXP EN: Enables/disables active interrupts on the ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register BAh: TX-F Enable FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) BAh TEMP bit7 Configures the maskable interrupt for the TX-F pin. ...
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Table 02h, Register BBh: TX-F Enable FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) BBh HTXP EN LTXP EN bit7 Configures the maskable interrupt for the Tx-F pin. HTXP EN: Enables/disables active interrupts on the ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register BCh: HTXP FACTORY DEFAULT: 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE BCh 2 2 bit7 Fast-comparison DAC threshold adjust for high transmit power. This value ...
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Table 02h, Register C0h: DPU FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) C0h RESERVED RESERVED bit7 Controls the power-on values for D3, D2, D1, and D0 output pins and mux and invertion of the ...
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PON Triplexer Control and Monitoring Circuit Table 02h, Register C5h to C6h: Reserved FACTORY DEFAULT: 0000 0000h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (SEE) These registers are reserved. Table 02h, Register C7h: M4 LUT Cntl FACTORY DEFAULT ...
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Table 02h, Register FAh: MAN_CNTL FACTORY DEFAULT: 00h READ ACCESS PW2 WRITE ACCESS PW2 and (Bias- MEMORY TYPE: Volatile FAh RESERVED RESERVED bit7 When BIAS-EN (Table 02h, Register 80h) is written to zero, bit zero of this byte ...
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PON Triplexer Control and Monitoring Circuit Table 03h, Register 80h to FFh: PW2 EEPROM FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (EE) 80h-FFh EE EE bit7 PW2 protected EEPROM. Table 04h, Register 80h to C7h: ...
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Table 05h, Register 80h to A3h: APC Tracking Error LUT (APC REF) FACTORY DEFAULT 00h READ ACCESS PW2 WRITE ACCESS PW2 MEMORY TYPE: Nonvolatile (EE 80h-A3h 2 2 bit7 The Tracking Error LUT is set of registers assigned ...
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... Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products is a registered trademark of Dallas Semiconductor Corporation. Springer Table 06h Register Descriptions Auxiliary Memory A0h Register Descriptions registered trademark of Maxim Integrated Products, Inc bit0 bit0 ...