ak2574 AKM Semiconductor, Inc., ak2574 Datasheet
ak2574
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ak2574 Summary of contents
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... TEMPSENS BIAS BIAS_ GEN RB (12k) <MS0266-E-00> The AK2574 is a 1chip LDD (Laser Diode Driver) and an APC (Auto Power Control) for burst mode application such as A TM-PON. It contains not only 156M LDD for modulatin current but also BIAS current switching, modulation currents, duty adjustment EEPROM for storing LD characteristics and user information ...
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... Duty Adjustment 2.4 APC 2.4.1 APC_FF 2.4.2 I-DAC 2.4.3 I-DAC2 Minimum Current Output 2.4.4 Temperature Sensor (TEMPSENS) 3. Alarm 3.1 TXACT 3.2 CLKALM 4. Shutdown I/F 5.1 Memory Map 5.2 Read / Write Operation 5.2.1 Byte Write 5.2.2 Page Write <MS0266-E-00> - Contents - -2- [AK2574 ...
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... Sequential Read 5.2.6 Data Change 5.2.7 Start / Stop Condition 5.3 EEPROM 5.4 Register 6. Operation Mode 6.1 Self-running Mode 6.2 Adjustment Mode 6.3 EEPROM Mode 6.4 MODE Control 6.5 Operation Mode Protection 6.6 Operation Mode Status 7. Module Adjustment Example . Circuit Example <MS0266-E-00> -3- [AK2574 2003/12 ...
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... CLKALM Sets the alarm when detects 1’ 0’ s sequential clock input. During CLKALM detection, the AK2574 goes into “ TX disable” . The detection time is 100ns (typ). The CLKALM is reset when 1 clock is detected. The polarity can be set with EEPROM. When SEL=” L” , CLKALM is set “ non-detected” polarity. ...
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... Power supply for digital circuit. Center PAD of PKG should be connected to the VSS for good electrical performance and radiation of heat. <MS0266-E-00> I PWR PWR Ao PWR PWR PWR Do Di PWR PWR -5- [AK2574] Remark AC load " 30pF DC load # 50k! Connect to VSS. 2003/12 ...
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... Address = 60h) for the offset of the on-chip temperature sensor. If such excess temperature stress applied to the AK2574 which exceeds a guaranteed EEPROM data retention conditions (for 10 years at 85 ), it is important to read the pre-determined value in advance and to re-write the same data back into EEPROM after an exposure to the excess temperature environment ...
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... IOH = -0.2mA 0.4 V IOL = 1mA (SDA) IOL = 0.2mA (Except SDA except WP pin 350 uA WP pin min max 100 4.7 4.0 100 0.1 4.5 4.7 4.7 4.0 0 200 1.0 0.3 4.7 100 10 tHD.DAT tSU.DAT tDH -7- [AK2574] Unit Remark kHz Note 1 us Note tSU.STO tBUF 2003/12 ...
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... VDD – 1.0 Vbias 0.6*VDD Zin 10 Conditions min typ 12.8 Last Data=1 R_DAC2=0Fh R_DAC2=0Fh 120 R_DAC2=2Fh 108 R_DAC2=FFh 98 R_DAC2=0Fh R_DAC2=0Fh Note 2 100% Nominal rib2 2ns Tdr-dt -8- [AK2574] max Unit Remarks 1 max Unit Remarks 150 % Note +/- 15 % Note Tdf-di ...
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... R_DAC2=2Fh 108 R_DAC2=FFh 98 R_DAC2=0Fh R_DAC2=0Fh Note 2 Th 100% Nominal rib2 2ns Tdr-dt min typ max 100 0.333 -1 +1 -9- [AK2574] max Unit Remarks Note 150 % Note +/- 15 % Note Th-b Tdf-di Tdf-bt Unit Remark bit mA uA TXDIS = “ 1” ...
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... Unit Remark bit mA mA R_DAC2 = R_DAC2 = 0 uA TXDIS = “ 1” mA LSB Code 20h to FFh max Unit Remarks ns Note Steps 0.2 ns Note 1 max Unit Remarks bit 0.94 V 0.84 V 0.74 V 0.64 V 0.54 V ...
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... ASAHI KASEI 15. ADC Item Condition Resolution Maximum Input Voltage Minimum Input Voltage DNL 16. Power On Reset Item Condition Detect Voltage When detects the voltage drop, the AK2574 goes into shutdown condition. 17. On-chip Oscillator Item Condition Clock Frequency <MS0266-E-00> min typ max Unit 7 bit 2 ...
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... ASAHI KASEI (1) Package Type: 48 pin BCC++ (2) Marking Information: (a) PIN#1 Indication: (b) Logo: AKM (c) Marking Code: AK2574VB (d) Date Code: YYWWXXX (7 digit) (3) Package Outline 7.00 <MS0266-E-00> . Package Information AKM AK2574VB YYWWXXX 6 5.1 5.50.06 "A" "C" 5.0 6.15 "B" Part "A" Part 0.05 C0.2 0.14 MIN ...
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... Operation Overview The AK2574 has 3 primary functions; 125M / 156M modulation (MOD) current switching and BIAS current switching part, APC (Automatic Power Control) part, and the Control part to control operation modes of the AK2574 operation. There are 3 operation modes in the AK2574. Since each adjusting function is controlled through I realizes an automatic parameter adjustment ...
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... BRTS=1. To protect the last LD current at BRST 1$0, BIAS current turned off timing is delayed for a duty extended when the last DATA=1. 2.2 LVPECL I/F (DATAP, DATAN, CLKP, CLKN, BRSTP, BRTSN) The AK2574 supports direct data or latched data input (see Table 2 -1). Connect CLKP = VDD or leave open and CLKN = VSS when SEL = “ L” . Table 2-1 Data input SEL (CMOS) “ ...
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... Input Timing (SEL=” H” the case of the latched DATA with CLK) BRST (BRSTP – BRSTN) and DATA (DATAP – DATAN) are shifted into AK2574 at the falling edge of CLK (CLKP – CLKN). BIAS driver is turned on within 2 clock (12.8ns max) when BRST = 1. DATA input should be 2 clock (= 12.8ns min) behind BRST = 1. Fig 2-5 illustrates the timing example. < ...
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... Input Timing (SEL=” L” the case of direct DATA) AK2574 operates without CLK when SEL=” L” . DATA input should be 12.8ns or more behind BRST = transition. To protect the last DATA, BRST 1$ 0 transition should be behind the last DATA input. Fig 2-6 illustrates the timing example ...
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... ASAHI KASEI 2.4 APC AK2574 provides the APC (Auto Power Control) function for the burst mode application. APC is composed of a programmable BIAS and MOD currents in response to the temperature (APC_FF), an on-chip temperature sensor, and 2 current DACs (I-DAC1 and I-DAC2). 2.4.1 APC_FF Fig 2-7 illustrates the APC_FF functions. The operation is as follows: (1) Analog to digital conversion of the voltage (7 bit) that reflects the temperature for every temperature detection period (128ms typ) ...
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... Note: Temperature sensor detects the junction temperature, not LD or ambient temperature. <MS0266-E-00> min typ max 1.06 1.2 0 0.212 -1 +1 Remarks IBIAS = Hi-Z 5 Code forced modification 100 120 -18- [AK2574] Unit Remark bit mA mA See 2.4 LSB Code 20h to FFh 2003/12 ...
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... AD code Temp [&] 44.2 96 -3.7 42.7 97 -5.2 41.2 98 -6.7 39.7 99 -8.2 38.2 100 -9.7 36.7 101 -11.2 35.2 102 -12.7 33.7 103 -14.2 32.2 104 -15.7 30.7 105 -17.2 29.2 106 -18.7 27.7 107 -20.2 26.3 108 -21.7 24.8 109 -23.2 23.3 110 -24.7 21.8 111 -26.2 20.3 112 -27.7 18.8 113 -29.2 17.3 114 -30 ...
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... Fig 3-1illustrates TXA CT block diagram. TXACT is detected when the PDIN voltage is beyond the reference voltage (txact_ref), and TXACT is held during BRST = “ H” . The txact_ref is set with RE_DAC_TX A CT. TXACT detection time depends on the Monitor PD current (i_pd) and capacitance (CMPD), external resistor (RPD), AK2574 PDIN capactance (CPDIN) and txact_ref voltage (see Fig 3-2 for the reference). ...
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... CLKALM CLKALM is detected when input CLK is 0’ 1’ s fixed more than 100ns (typ). The polarity of CLKALM can be set by RE_CLKALM_POL (0: “ H” at detection, 1: “ L” at detection). AK2574 goes into “ shutdown” (see 4. Shutdown) when CLKALM is detected. 4. Shutdown Table 4-1 shows the shutdown condition and Table 4-2 shows AK2574 operation at shutdown. AK2574 goes into “ ...
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... No memory 11111111 100 00000000 to Registers 00010011 100 00010011 to No memory 11111110 100 11111111 AK2574 Operation mode change WP = “ H” 1010000 when receive device address User area only (read only) Self running mode only from 00000000 to 01111111 -22- [AK2574 Data ...
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... Address-1 Address 5.2.4 Random Read A random read requires a “ dummy” byte write sequence to specified “ Address” . After receive the ACK from AK2574, perform “ current address read” (see 5.2.2 SDA Device Device ...
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... EEPROM after an exposure to the excess temperature environment. Even if the exposure time is shorter than the retention time, any accelerated temperature stress tests (such as baking) are performed recommended to read the pre-set data first and to re-write it after the tests. <MS0266-E-00> STOP -24- [AK2574] 2003/12 ...
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... TXDIS_ Reserved -25- [AK2574] Remark Addressing with R_TEMP (1.5& step) Addressing with R_TEMP (1.5& step) Addressing with MSB 5bit of R_TEMP (6& step) Remark 0: Shutdown at “H” 1: Shutdown at “ L” 0: “ H” at TXACT detection 1: “ L” at TXACT detection 0: “ ...
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... D4 D3 TXDIS_ POL DAC1 DAC2 DUTY TEMP Reserved (AKM Test) -26- [AK2574] Remark 0: Shutdown at “H” 1: Shutdown at “ L” 0: “ H” at TXACT detection 1: “ L” at TXACT detection 0: “ H” at CLKALM detection 1: “ L” at CLKALM detection see Table 3-2 0: TXACT Hold (Normal Operation) 1: TXACT (Real-Time) ...
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... Self-running mode is ready for normal operation after all adjustments are completed. In this mode, temperature detection, EEPROM access and feeding current are automatically performed using the on-chip oscillator. The AK2574 works in this mode after power-on. 6.2 Adjustment Mode Adjustment mode is designed for training the LD characteristics. The AK2574 operates according to the register settings set through the I/F ...
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... Go to Adjustment mode Issues “ Changing to Adjustment mode command” (see Table 5-2) via I 2 Continuous operation Set BRST=” H” to operate AK2574 as a continuous operation current adjustment Adjust R_DAC1 for modulation current and R_DAC2 for BIAS current of LD. 4 Duty adjustment Adjust R_DUTY for 50% duty of LD power, if necessary ...
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... ASAHI KASEI Fig-A illustrates circuit example of AK2574. Fig-A Circuit Example C19 C17 C20 IBIASC2 R1 IBIASR1 PDIN TESTMON R3 R2 BIAS AK2574VB AVDD C22 C21 AVSS TXACT TEST1 DVSS DVDD R5 C11 C12 VCC or GND 1 Pull-up or pull down R6 Do not leave open ...
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... AKM harmless from any and all claims arising from the use of said product in the absence of such notification. <MS0266-E-00> IMPORTANT NOTICE -30- [AK2574] 2003/12 ...