CXA3092N 4ch. Read/Write Amplifier for Thin Film Head of Hard Disk Drive For the availability of this product, please contact the sales office. Description The CXA3092N is a Read/Write Amplifier for the thin film head of hard disk drive and designed to handle up to 4 channel heads. Features • Operate on single +5 V power supply • Low power consumption Read : 85 mW Write : 115 mW + IW ×5 Idle : 8 mW • Designed for two terminal thin-film or MIG heads • Read amplifier emitter follower output featuring 325 times gain (typ). • Differential input capacitance for Read : 6pF (typ) • Input noise : 0.47 nV / √ Hz (typ) • Write current range : 5 to 15 mA • Differential Head voltage swing : 6.8 Vp-p (typ) • Differential P-ECL write data input • Built-in write unsafe detection circuit. • Built-in Servo write function (2/4 ch). • Built-in IC protection circuit for short of head to 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 = 350 Ω). 20 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 800 mW PD • 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— E96713-TE CXA3092N Block Diagram and Pin Configuration GND 1 20 XCS MODE CONTROL H0X 2 H0Y 3 H1X 4 19 R/W DRIVER WRITE CURRENT SOURCE AMP 18 WC 17 RDY 16 RDX DRIVER AMP H1Y 5 H2X 6 AMP 15 HS0 DRIVER HEAD SELECT H2Y 7 H3X 8 AMP 14 HS1 13 WDX 12 WDY DRIVER IC PROTECTOR H3Y 9 VCC 10 AMP POWER ON/OFF DETECTOR WRITE UNSAFE DETECTOR —2— 11 WUS/SE CXA3092N Pin Description No. Symbol 1 GND Description Equivalent circuit 2 VCC 4 2 3 4 5 6 7 8 9 H0X H0Y H1X H1Y H2X H2Y H3X H3Y 6 8 2k 2k Head. 4 channels provided. 3 5 7 9 GND 10 VCC 5 V power supply. VCC 11 Write unsafe detection output / Servo Enable signal input. 11 WUS/SE GND VCC 12 13 WDY WDX 12 Differential P-ECL write data input. 13 GND —3— CXA3092N No. Symbol Description Equivalent circuit VCC 14 15 HS1 HS0 Head select signal input. Selects one of 4 heads according to Table 2. 14 15 2.1V 100k GND VCC 16 17 16 RDX RDY Read Amplifier output. 17 GND VCC 18 A setting resistor for the write current value is connected between this pin and GND. WC 18 2V GND VCC Read/Write signal input At “High” : Read, at “Low” : Write. 100k 19 R/W 19 2.1V GND VCC 20 XCS Power save signal input At “High” : Power save. 20 2.1V 100k GND —4— —5— 3-2 3-1 2-8 2-7 2-6 2-5 2-4 2-3 2-2 2-1 1-3 1-2 1-1 No. Current consumption for Read Current consumption for Write Current consumption for idle 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 Item Electrical Characteristics a ICCI b a IWUS a a VWUS Vunsel IWD VWDH VWDL IIH IIL VIH a a ICCW VIL a 1 ICCR Symbol a a a a a a a a 2 a a a a a a a a 3 a a a a a a a a 4 a b a a a a a a 5 a b b b b b b b a a a a a a a a a c a a a a a a b c b b b b b b a c a b a a a a a c a b a a a a b b b b b b b b a a a b a a a b a a a b a b a a SW conditions 6 7 8 9 10 11 12 13 14 Test point : l3 Output current : 1 mA Test point : V1 Input voltage : 4 V “High” applied voltage : 5 V “Low” applied voltage : 0 V Test point : l6, l7, l8, I9 Digital input : Pins 17, 18, 19, 23 Test point : I2 Test point : l2 Test point : l2 Measurement conditions VWDH –2.0 VCC –1.1 –100 2.0 1.6 50 0.5 0.3 50 VWDH –0.25 VCC –0.4 100 0.8 2.3 23 +IW 17 +IW 1.0 36 +IW 17 12 26 µA V V µA V V µA µA V V mA mA mA Min. Typ. Max. Unit (Unless otherwise specified, VCC=5 V, Ta=25 °C, Write current IW=15 mA) Refer to Fig.1 CXA3092N AW KW Write current gain Write current setting constant WUS/SE voltage 5-3 5-4 6-1 6-2 a a a 4 a a b a a b a a b a a b a a b b a a a a IW=AW • VWC/RWC Write mode and IW does not flow anymore, VCC voltage is set to VTHOFF. When VCC is raised from 3 V and IW starts to flow, VCC voltage is set to VTHON. When VCC is lowered from 5 V in Measurement conditions 3.4 b b a a a a IW=KW/RWC —6— b b a a a a a a c c b b a a a a b b a a a a b b b b a a Input voltage SG1 : 1 mVp-p, 300 kHz Load resistance (RDX, RDY) : 1 kΩ Test point : V4 [Vp-p] V4 AV = SG1 Frequency at which AV lowers by 3 dB BW a a Frequency band width (–3 dB) a a 8 b b AV a a Read amplifier differential voltage gain b a 7 b b Servo write enabled a a ISEH a a WUS/SE sink current a a Servo write enabled a a VSEH b b 70 275 0.5 VCC +1 46.8 23.4 100 325 52 26 2 3.9 V mAo-p V 375 14 VCC +1.2 57.2 MHz V/V mA V 28.6 mA/mA 2.2 15 4.3 Min. Typ. Max. Unit 1.8 a a 3 VWC a a 2 5 Write current voltage b 1 SW conditions 5 6 7 8 9 10 11 12 13 14 IW 5-2 VTH Symbol Write current setting range Supply power ON/OFF detector threshold voltage Item 5-1 4 No. CXA3092N Input referred noise Common mode rejection ration Power supply rejection ratio 10 11 Item 9 No. PSRR CMRR EN Symbol a b a 1 a a a 2 a a a 3 a a a 4 a d a a b b a a a a a a b b b a a a a a a b b b b b b a a a SW conditions 5 6 7 8 9 10 11 12 13 14 100 CMRR = 20 log VCM +20 log AV Test point : V4 Ripple voltage SG3 : 100 mVp-p, 5 MHz When the Read amplifier output is VP [mVp-p], 100 PSRR = 20 log VP +20 log AV Test point : V4 EN = VN 100 • AV√ 15 × 106 Test point : V5 In-phase input voltage SG2 : 100 mVp-p, 5 MHz When the Read amplifier output is VCM [mVp-p], Head impedance : 0 Ω, when the read amplifier output voltage is amplified 100 times and voltage passed though a LPF (low pass filter of cutoff frequency 15 MHz) is VN [Vrms], Measurement conditions 50 50 0.47 0.65 dB dB nV √ Hz Min. Typ. Max. Unit CXA3092N —7— Channel separation Read data output offset voltage for Read 13 Item 12 No. VOFFR CS Symbol a a 1 a b 2 a a 3 a a 4 e c b b a a a a b b a a a a a b b b a a SW conditions 5 6 7 8 9 10 11 12 13 14 Selected head input voltage : 0 mVp-p Unselected head input voltage SG1 : 100 mVp-p, 5 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 Measurement conditions –250 50 250 mV dB Min. Typ. Max. Unit CXA3092N —8— CXA3092N 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. 14 Item Head differential voltage amplitude Mode switching time 15-1 Read to Write Symbol Measurement conditions VSW Differential voltage between HX pin and HY pin at switching of Write current (open Head) 5.8 6.8 Vp-p to 90 % after Pin 19 changes from “High” to “Low”. TWR1 is the time required for the Read amplifier output∗ to turn to 90 % after Pin 19 changes from “Low” to “High”. TWR2 is the time required for Write current to decreases to 10 % after Pin 19 changes from “Low” to “High”. TIR is the time required for the Read amplifier output∗ to turn to 90 % after Pin 20 changes from “High” to “Low”. TSA1 is the time required for Pin 11 to turn “High” after the last transition of Write data 1.5 when Write data is stopped in Write mode. TSA2 is the time required for Pin 11 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. LH=0 µH, RH=0 Ω 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 0.2 0.4 µs 0.3 0.5 µs 0.2 0.4 µs 1 µs 5 µs 0.6 µs 0.6 µs 2 7 ns 1 3 ns TRW is the time required for Write current to turn TRW TWR1 15-2 Min. Typ. Max. Unit Mode switching time Write to Read TWR2 16 Mode switching time to Read TIR 17-1 Mode switching time safe to unsafe TSA1 17-2 Mode switching time unsafe to safe TSA2 18 Head switching time TH 19 Write current propagation delay time TPD 20 Write current rise/fall time TR/TF ∗Read amplifier output 100 mVp-p 10 MHz —9— 3 CXA3092N Test Circuit 1 VCC 5V 1µ 1k 1k ×100 LPF A AMP to15MHz V AMP S6 V 1µ V4 PG 1µ V b a S13 b a a b S12 A I9 a b S11 4V abc S10 A 3.3k I8 6V V 3V S14 A SG4 V2 5V a b 5.1k PG SG5 V3 a b I2 SG3 a b ×1 V5 VCC 5V S9 A I7 a b abc S8 A I6 A I4 I3 20 19 18 17 16 15 14 13 12 11 1 2 3 4 5 6 7 8 9 10 S1 a b S2 a b a b S3 a b a b V1 S7 A I5 V S4 a b a b a b S5 a b c d e A a b c d e 0.1µ I1 Fig. 1 SG2 33 0.1µ 0.1µ SG1 Test Circuit 2 1k 1k ×1 AMP 1µ 1µ 1µ PG PG 20 19 18 17 16 1 2 3 4 5 PG PG PG 15 14 13 12 11 6 7 8 9 10 3.3k LH LH LH LH 1µH 1µH 1µH 1µH —10— 5.1k 5V Fig. 2 CXA3092N Timing Chart 1 WDX WDY R/W 50% 50% 50% PS TRW TWR 2 90% 90% IWX IWY 10% 10% TWR1 TIR 90% RDX RDY 90% Fig. 3 Timing Chart 2 WDX WDY TPD IWX IWY 90% 90% 10% 10% TR WUS 90% TF 50% TSA1 50% TSA2 Fig. 4 —11— CXA3092N Description of 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 XCS, R/W and WUS/SE. XCS R/W WUS/SE HS0 HS1 L L X See Table 2 L H X L L ∗∗ See Table 3 H X X X X Table 1. Mode selection Mode Write Read Servo Write Idle Head selection The heads are selected as shown in Table 2 by the HS0 and HS1 pins. HS0 HS1 Head L L 0 H L 1 L H 2 H H 3 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— CXA3092N 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 H L 0, 1, 2, 3 L H 2, 3 H H 0, 1, 2, 3 Table 3. Head selection in Servo Write mode —13— CXA3092N Application Circuit 1µ PULSE DETECTOR RW 3.3k 5.1k 20 19 18 17 16 15 14 13 12 11 1 2 3 4 5 6 7 8 9 10 LH LH LH LH 1µH 1µH 1µH 1µH 5V 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— CXA3092N 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-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 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— CXA3092N Application Notes Use the following characteristics for reference. VCC=5V, Ta=25 °C Item Symbol Differential output capacitance Differential output resistance Differential input capacitance Read mode Differential input resistance Output resistance Unselected head differential current in Write mode CO RO CI RI RRD Write current symmetry TAS∗ Write mode Conditions Between head input pins Unit 10 440 10 pF Ω pF kΩ Ω 260 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 IUS Min. Typ. Max. 0.6 50 0.2 mAp-p –0.5 ∗TAS=T1–T2 IWX+IWY 50% 50% T1 50% T2 WC Setting of Write current Write current can be set with resistor RWC (kΩ) at Pin 18. IW=K/RWC (mA) Refer to Fig. 5. Fig.5 Write current vs. RWC IW -Write current (mA) 20 10 5 2 5 10 15 RWC (kΩ) —16— 350 6 1.2 18 RWC 0.5 ns CXA3092N Normalized write current vs. Supply voltage Normalized write current vs. Ambient temperature Ta=25°C RWC=3.3kΩ 1.02 1 0.96 0.96 5 6 –25 0 25 75 50 Supply voltage VCC [V] Ambient temperature Ta [°C] Normalized read amplifier voltage tgain vs. Supply voltage Normalized read amplifier voltage gain vs. Ambient temperature Ta=25°C 1.02 1 0.98 0.96 VCC=5V 1.04 AV/AV (Ta=25°C) AV/AV (VCC=5V) 1 0.98 1.04 1.02 1 0.98 0.96 4 5 6 –25 Supply voltage VCC [V] 4.2 OFF → ON 4 ON →OFF 3.8 3.6 –25 0 25 50 0 25 50 Ambient temperature Ta [°C] Power supply ON/OFF detector threshold voltage vs. Ambient temperature Power supply ON/OFF Detector Threshold Voltage [V] 1.02 0.98 4 VCC=5V RWC=3.3kΩ 1.04 IW/IW (Ta=25°C) IW/IW (VCC=5V) 1.04 75 Ambient temperature Ta [°C] —17— 75 CXA3092N Package Outline Unit : mm 20PIN SSOP(PLASTIC) 2.0MAX 7.2 ± 0.3 0.15 5.3 ± 0.3 11 1 7.8 ± 0.4 20 A 10 0.83MAX 0.3 ± 0.1 0.15 ± 0.05 0.13 M 0.65 0.05MIN DETAIL A 0.75 ± 0.2 10°MAX PACKAGE STRUCTURE PACKAGE MATERIAL EPOXY RESIN PALLADIUM PLATING SONY CODE SSOP-20P-L122 LEAD TREATMENT EIAJ CODE SSOP020-P-0300 LEAD MATERIAL COPPER ALLOY PACKAGE MASS 0.15g JEDEC CODE NOTE : PALLADIUM PLATING This product uses PdPPF (Palladium Pre-Plated Lead Frame). —18—