CXA3170AN

CXA3170AN 6ch. Read/Write Amplifier for Thin Film Head of Hard Disk Drive For the availability of this product, please contact the sales office. Description The CXA3170AN is a Read/Write Amplifier for the thin film head of hard disk drive and designed to handle up to 6 channel heads. Features • Operate on single +5 V power supply • Low power consumption Read : 85 mW Write : 115 mW + IW ×5 • Designed for two terminal thin-film or MIG heads • Read amplifier emitter follower output featuring 360 times gain (typ). • Differential input capacitance for Read : 6 pF (typ) • Input noise : 0.47 nV / √ Hz (typ) • Write current range : 5 to 15 mA • Differential Head voltage swing : 9 Vp-p (typ) • IW Rise / Fall times : 3.7 ns (typ) • • • • • • • (LH=540 nH, RH=25 Ω, IW=10 mA) Differential P-ECL write data input Built-in write unsafe detection circuit. Built-in Servo write function (3/6 ch). Built-in IC protection circuit for short of head and GND. Read data outputs are high impedance in write mode. Unselected head voltage is GND potential. Built-in supply voltage monitor circuit prohibits incorrect write during power on or abnormal voltage. Self switching damping resistance (RD = 360 Ω). 24 pin SSOP (Plastic) Absolute Maximum Ratings (Ta=25 °C) • Supply voltage VCC 6 V • Write current IW 20 mAo-p • Operating temperature Topr –20 to +75 °C • Storage temperature Tstg –55 to +150 °C • Allowable power dissipation PD 800 mW • WUS/SE pin input current ISEH 15 mA Recommended Operating Conditions • Supply voltage VCC 5.0 V±10 % • Write current IW 5 to 15 mAo-p • Function Read, Write and Write unsafe detection for HDD, power supply ON/OFF detection. Structure Bipolar silicon monolithic IC Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits. —1— E97640 CXA3170AN H0X 1 DRIVER 24 GND MODE CONTROL H0Y 2 AMP 23 R/W H1X 3 DRIVER WRITE CURRENT SOURCE 22 WC H1Y 4 AMP 21 RDY AMP H2X 5 DRIVER 20 RDX AMP H2Y 6 19 HS0 H3X 7 DRIVER HEAD SELECT 18 HS1 H3Y 8 AMP 17 HS2 H4X 9 DRIVER 16 WDX H4Y 10 AMP 15 WDY H5X 11 DRIVER WRITE UNSAFE DETECTOR POWER ON/OFF DETECTOR IC PROTECTOR 14 WUS/SE H5Y 12 AMP 13 VCC —2— CXA3170AN Pin Description No. 24 Symbol GND 1 VCC Equivalent circuit Description 1 2 3 4 5 6 7 8 9 10 11 12 H0X H0Y H1X H1Y H2X H2Y H3X H3Y H4X H4Y H5X H5Y 3 5 7 9 11 2k 2k 2 4 6 8 10 12 GND 100K Head. 6 channels provided. VCC 14 WUS/SE 14 Write unsafe detection output / Servo Enable signal input. GND VCC 15 16 WDY WDX 15 16 Differential P-ECL write data input. GND 13 VCC 5 V power supply. —3— CXA3170AN No. Symbol Equivalent circuit Description VCC 17 18 19 100k 2.1V GND 17 18 19 HS2 HS1 HS0 Head select signal input. Selects one of 6 heads according to Table 2. VCC 100k 23 R/W 23 Read/Write signal input At “High” : Read, at “Low” : Write. 2.1V GND VCC 20 21 RDX RDY 20 Read Amplifier output. 21 GND VCC 22 WC 22 2.5V GND A setting resistor for the write current value is connected between this pin and GND. —4— Electrical Characteristics SW conditions 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Measurement conditions Min. Typ. Max. Unit 11 16 +IW +IW 22 36 +IW 0.8 2.0 –100 100 17 26 mA mA V V µA µA V V 50 0.3 baaaaabbaccaaaba Output current : 1 mA Test point : V1 0.5 50 µA V V µA a a a a a a e b a a b a a a b b Test point : l2 a a a a a a e b a a b a a a b a Test point : l2 (Unless otherwise specified, VCC=5 V, Ta=25 °C, Write current IW=15 mA) No. Item Symbol 1-1 IR 1-2 IWR 2-1 Digital input : Pins 17, 18, 19, 23 VIL 2-2 a a a a a a e b a a b a a a b a “High” applied voltage : 5 V “Low” applied voltage : 0 V a a a a a a e b a a b b b b b b Test point : l6, l7, l8, I9 VIH 2-3 IIL 2-4 IIH —5— a a a a a a e b a a b a a a b a Test point : l3 2-5 VWDL 2-6 VWDH a a a a a a e b a a b a a a a a Input voltage : 4 V VWDH –2.0 VCC –1.1 VWDH –0.25 VCC –0.4 2-7 IWD 2-8 Vunsel 3-1 VWUS 3-2 Current consumption for Read Current consumption for Write Digital input “Low” input voltage Digital input “High” input voltage Digital input “Low” input current Digital input “High” input current Write data input “Low” input voltage Write data input “High” input voltage Write data input current Unselected head voltage Write unsafe output saturation voltage Write unsafe output leak current IWUS CXA3170AN 4 Supply power ON/OFF detector threshold voltage VTH When VCC is lowered from 5 V in Write mode and IW does not flow anymore, VCC voltage is set to baaaaaabaabaaaba VTHOFF. When VCC is raised from 3 V and IW starts to flow, VCC voltage is set to VTHON. 3.4 3.9 4.3 V No. 5 aaaaaaebaabaaaaa 2.25 IW=AW • VWC/RWC 18 45 VCC +1.5 5 b a a a a a a b a a b a a a b a IW=KW/RWC b a a a a a a b b a a a a a b a Servo write enabled b a a a a a a b b a a a a a b a Servo write enabled 20 50 2.5 2.75 15 mAo-p V 22 mA/mA 55 VCC +1.6 14 V Item Symbol SW conditions 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Measurement conditions Min. Typ. Max. Unit 5-1 Write current setting range IW 5-2 Write current voltage VWC 5-3 Write current gain AW 5-4 Write current setting constant KW 6-1 WUS/SE voltage VSEH 6-2 WUS/SE sink current ISEH mA —6— 7 Read amplifier differential voltage gain AV 305 360 415 V/V 8 Frequency band width (–3 dB) BW 100 140 MHz 9 Input referred noise EN Input voltage SG1 : 1 mVp-p, 300 kHz Load resistance (RDX, RDY) : b a a a a a c b a a b a a a b b 1 kΩ Test point : V4 [Vp-p] V4 AV = SG1 Frequency at which AV lowers baaaaacbaabaaabb by 3 dB Head impedance : 0 Ω, when the read amplifier output voltage is amplified 100 times and voltage passed though a a a a a a a e b a a b a a a b b LPF (low pass filter of cutoff frequency 15 MHz) is VN [Vrms], VN EN = 100 • AV√ 15 × 106 Test point : V5 0.47 0.6 nV √ Hz CXA3170AN No. Measurement conditions Item Symbol SW conditions 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Min. Typ. Max. Unit 10 Common mode rejection ration 50 CMRR b a a a a a d b a a b a a a b b dB 11 aaaaaaeaaabaaabb Power supply rejection ratio PSRR 50 dB —7— abaaaacbaabaaabb aaaaaaebaabaaaab 12 Channel separation CS 50 dB 13 Read data output VOFFR offset voltage for Read In-phase input voltage SG2 : 100 mVp-p, 20 MHz When the Read amplifier output is VCM [mVp-p], 100 CMRR = 20 log VCM +20 log AV Test point : V4 Ripple voltage SG3 : 100 mVp-p, 20 MHz When the Read amplifier output is VP [mVp-p], 100 PSRR = 20 log VP +20 log AV Test point : V4 Selected head input voltage : 0 mVp-p Unselected head input voltage SG1 : 100 mVp-p, 20 MHz When the Read amplifier output is VCS [mVp-p], 100 CS = 20 log VCS +20 log AV Test point : V4 VOFFR = V2–V3 Test point : V2, V3 –250 250 mV CXA3170AN No. Item Symbol SW conditions 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Measurement conditions Min. Typ. Max. Unit 14 RDX, RDY common mode output voltage difference between modes aaaaaaebaabaaabc –300 300 Test point : Pin 20, 21 mV Vdiff 15 RDX, RDY common mode output voltage for Read a a a a a a e b a a b a a a a b Test point : V2, V3 VCC –2.6 VRD VCC VCC –2.3 –2.0 V —8— CXA3170AN CXA3170AN Unless otherwise specified, VCC=5 V, Ta=25 °C, fWD (Write data frequency) =5 MHz, IW=15 mA, LH (Head inductance) =1 µH, RH (Head DC resistance value) =30 Ω Refer to Fig. 2 to Fig. 4 No. Item Head differential voltage amplitude Symbol Measurement conditions Differential voltage between HX pin and HY pin at switching of Write current TRW is the time required for Write current to turn to 90 % after Pin 23 changes from “High” to “Low”. TWR1 is the time required for the Read amplifier output∗ to turn to 90 % after Pin 23 changes from “Low” to “High”. TWR2 is the time required for Write current to decreases to 10 % after Pin 23 changes from “Low” to “High”. TSA1 is the time required for Pin 14 to turn “High” after the last transition of Write data 1.0 when Write data is stopped in Write mode. TSA2 is the time required for Pin 14 to turn “Low” after the first transition of Write data in Write mode. TH is the time required for the Read amplifier output∗ to reach 90 % when the selected head switched in Read mode. TPD is the time required for Write current to reach 90 % after the Write data falling edge. TR is the time required for Write current to reach 90 % from 10 %; TF is the same time required to reach 10 % from 90 %. LH=0 µH, RH=0 Ω LH=540 nH, RH=25 Ω, IW=10 mA TR is the time required for Write current to reach 90 % from 10 %; TF is the same time required to reach 10 % from 90 %. Min. Typ. Max. Unit 14 VSW 9 Vp-p Mode switching time 15-1 Read to Write TRW 130 150 ns TWR1 15-2 Mode switching time Write to Read TWR2 180 220 ns 100 200 ns 16-1 Mode switching time safe to unsafe Mode switching time unsafe to safe TSA1 2.3 3.0 µs 16-2 TSA2 0.6 µs 17 Head switching time Write current propagation delay time TH 0.6 µs 18 TPD 2 7 ns Write current 19-1 rise/fall time TR/TF 1 3 ns 19-2 Write current rise/fall time TR/TF 3.7 ns ∗Read amplifier output 100 mVp-p 10 MHz —9— CXA3170AN Test Circuit 1 1µ LPF ×100 AMP ×1 SG3 ab S8 1µ SG6 PG 5V abc S16 ba 1µ PG SG5 PG SG4 I14 5.1k 6.5V VCC 5V VCC 5V A I2 V V5 to15MHz V V4 AMP V V3 ba S15 V V2 ab ab S14 ab S13 3V abc S12 S11 4V a bc ab S9 A V V1 S10 A 24 23 I9 3.3k 22 21 20 A 19 I8 A 18 I7 A 17 I6 A 16 I5 A 15 I4 A 14 I3 13 1 S1 ab 2 3 S2 ab 4 5 S3 ab 6 7 S4 ab 8 9 S5 ab 10 11 S6 ab 12 ab ab ab ab ab ab S7 abcde abcde I1 33 0.1µ SG2 0.1µ 0.1µ A Fig. 1 SG1 Test Circuit 2 1k ×1 AMP 1µ 5V 1k 1µ PG 3.3k 1µ PG PG PG 5.1k 24 23 22 21 20 19 18 17 16 15 14 13 1 LH 1µH 2 3 LH 1µH 4 5 LH 1µH 6 7 LH 1µH 8 9 LH 1µH 10 11 LH 1µH 12 Fig. 2 —10— CXA3170AN Timing Chart 1 WDX WDY R/W 50% 50% TRW TWR 2 90% IWX IWY 10% 90% 10% TWR1 RDX RDY 90% Fig. 3 Timing Chart 2 WDX WDY TPD 90% 10% TR 90% 90% 10% TF TSA1 IWX IWY WUS TSA2 50% 50% Fig. 4 —11— CXA3170AN Description Functions Read amplifier This is a low noise amplifier for amplifying the signals from the heads with an emitter follower output. The RDX and RDY are the outputs of the differential amplifier whose polarity between the RDX and X side of the head input is same. Write circuit The Write data input to WDX pin and WDY pin passes through the buffer amp. It drives the Write switch circuit which supplies the Write current to the heads. The Write current flows into the X side when WDX is “Low” and WDY is “High”. Mode control The mode are set as shown Table 1 by R/W and WUS/SE. R/W WUS/SE HS0 HS1 HS2 L X See Table 2 H X L ∗∗ See Table 3 X Table 1. Mode selection Mode Write Read Servo Write Head selection The heads are selected as shown in Table 2 by the HS0, HS1 and HS2 pins. HS0 HS1 HS2 Head L L L 0 H L L 1 L H L 2 H H L 3 L L H 4 H L H 5 Table 2. Head selection Servo write mode ∗∗ This mode allows for writing to multiple channels at once. To enable servo write mode follow these steps: (1) Place the device in the Read mode. (2) Set HS0 and HS1 following Table 3. (3) Set WUS/SE to VSEH, or input ISEH to WUS/SE. (4) While maintaing step (2) and (3) above make R/W low, placing the device in servo write mode. —12— CXA3170AN Write unsafe detection circuit This circuit detects write errors. In normal Write mode, the WUS output is low; in the conditions listed below, it is high. • Head inputs is open (under the condition which. RH=∞ and Write data frequency is ≤ 10 MHz) • Head input is shorted to GND or VCC. • Write data frequency is abnormally low. • No write current. • In read mode. • Supply voltage is abnormal (see power supply ON/OFF detection). Power supply ON/OFF detection This circuit monitors VCC to detect erroneous Writes. The error status is established when VCC falls below the threshold voltage (VTH) of the power supply ON/OFF detector, in which case the recording and playback functions are prohibited. When VCC rises above, VTH, the prohibition of these functions is released. HS0 HS1 Head L L 0, 1, 2 H L 0, 1, 2, 3, 4, 5 L H 3, 4, 5 H H 0, 1, 2, 3, 4, 5 Table 3. Head selection in Servo Write mode —13— CXA3170AN Application Circuit +5V 1µ RWC 3.3k 5.1k 24 23 22 21 20 19 18 17 16 15 14 13 1 LH 1µH 2 3 LH 1µH 4 5 LH 1µH 6 7 LH 1µH 8 9 LH 1µH 10 11 LH 1µH 12 Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same. —14— CXA3170AN Notes on operation • This device handles high frequency and high gain signals. Please note the following; ♦ Connect VCC decoupling capacitor of approximately 1000 pF near the device. ♦ Make the GND area as large as possible. • When using as 2 or 4-channel, short-circuit the X and Y sides of unused head pins or leave them open. • The WC pin is a constant voltage pin. When noise affects this pin, it creates noise in Write c current. Therefore, locate RWC as close to the device as possible. • Write unsafe detection circuit This circuit uses the voltage waveforms of the head pins for detection. Wave form of write data Voltage waveform of head pins (HX, HY) VFB VTH=1.4V VTH GND ♦ VFB must be more than 2 V. When VFB < 2 V, it is possible that Write unsafe detection maximum frequency becomes more than 1 MHz. ♦ The normal operating area of write unsafe detection circuit is changed by head inductance, head DC resistance, write current and other. —15— CXA3170AN Application Notes Use the following characteristics for reference. Item Differential output capacitance Differential output resistance Differential input capacitance Read mode Differential input resistance Output resistance Unselected head differential current in Write mode Write mode Write current symmetry ∗TAS=T1–T2 Symbol CO RO CI RI RRD IUS TAS∗ Conditions Between head input pins Between head input pins f=5 MHz RDX or RDY, f=5 MHz LH=1 µH, RH=30 Ω IW=15 mA LH=0 µH, RH=0 Ω IW=15 mA VCC=5 V, Ta=25 °C Min. Typ. Max. 4.5 6 260 360 470 6 10 650 1500 3000 50 Unit pF Ω pF Ω Ω 0.2 mAp-p –0.5 0.5 ns IWX+IWY 50% T1 50% T2 50% WC Setting of Write current Write current can be set with resistor RWC (kΩ) at Pin 22. IW=K/RWC (mA) Refer to Fig. 5. 22 RWC Fig.5 Write current vs. RWC Fig.6 Write current setting constant vs. Write current Write current setting constant K 20 55 IW-Write current (mA) 52.5 K=RWC ·IW 50 10 5 47.5 45 2 5 RWC (kΩ) 10 15 4 6 8 10 12 14 16 Write Current IW (mA) —16— CXA3170AN Normalized write current vs. Supply voltage 1.04 Ta=25°C RWC=3.3kΩ 1.04 Normalized write current vs. Ambient temperature VCC=5V RWC=3.3kΩ IW/IW (Ta=25°C) IW/IW (VCC=5V) 1.02 1.02 1 1 0.98 0.98 0.96 4 5 Supply voltage VCC [V] 6 0.96 –25 0 25 50 75 Ambient temperature Ta [°C] Normalized read amplifier voltage tgain vs. Supply voltage 1.04 Ta=25°C 1.04 Normalized read amplifier voltage gain vs. Ambient temperature VCC=5V 1 AV/AV (Ta=25°C) AV/AV (VCC=5V) 1.02 1.02 1 0.98 0.98 0.96 4 5 Supply voltage VCC [V] 6 0.96 –25 0 25 50 75 Ambient temperature Ta [°C] Power supply ON/OFF detector threshold voltage vs. Ambient temperature 4.2 Power supply ON/OFF Detector Threshold Voltage [V] OFF → ON 4 ON →OFF 3.8 3.6 –25 0 25 50 75 Ambient temperature Ta [°C] —17— CXA3170AN Package Outline Unit : mm 24PIN SSOP(PLASTIC) + 0.2 1.25 – 0.1 ∗7.8 ± 0.1 0.1 13 24 A 1 + 0.1 0.22 – 0.05 12 + 0.05 0.15 – 0.02 0.65 0.1 ± 0.1 0.13 M ∗5.6 ± 0.1 0° to 10° NOTE: Dimensions “∗” does not include mold protrusion. DETAIL A PACKAGE STRUCTURE PACKAGE MATERIAL SONY CODE EIAJ CODE JEDEC CODE SSOP-24P-L01 SSOP024-P-0056 LEAD TREATMENT LEAD MATERIAL PACKAGE MASS EPOXY RESIN SOLDER/PALLADIUM PLATING 42/COPPER ALLOY 0.1g NOTE : PALLADIUM PLATING This product uses S-PdPPF (Sony Spec.-Palladium Pre-Plated Lead Frame). —18— 0.5 ± 0.2 7.6 ± 0.2