Datasheet Linear Constant Current VCM Driver BU64241GWZ ●General Description The BU64241GWZ is designed to drive voice coil motor (VCM). The driver includes ISRC (intelligent slew rate control) to reduce mechanical ringing to optimize the camera’s auto focus capabilities. ●Key Specifications ■ Power supply range ■ Standby current ■ Internal resistance ■ Master clock ■ Output maximum current ●Features ■ 2.3 V min driver power supply ■ Current sink output ■ 10 bit resolution current control ■ ISRC mechanical ringing compensation ■ 2-wire serial interface ■ Integrated current sense resistor 2.3 to 4.8 V 0 µA (typ.) 1.5 Ω (typ.) 400 kHz (typ.) 130 mA (typ.) ●Package W (Typ.) ×D (Typ.) ×H (Max.) 1.30 mm × 0.77 mm × 0.33 mm UCSP30L1 ●Applications ■ Autofocus in mobile camera modules ■ Driving VCM actuators ●Typical Application Circuit 0.1 to 10µF VCC VCC VCC PS Power Save GPIO TSD & UVLO Band Gap HOST ISINK OUT SDA 2-wire Serial Bus Interface & Ringing Control 2-wire serial Master Pre-driver SCL 10 OSC V/I 10 bit DAC Convertor RNF 1.8V Band Gap VREF GND Figure 1. Typical Application Circuit ○Product structure：Silicon monolithic integrated circuit .www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・14・001 ○This product is not designed protection against radioactive rays 1/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Pin Configuration 1 2 3 A PS SDA SCL B OUT GND VCC Figure 2. Pin configuration (TOP VIEW) ●Pin Description Ball Name PS Function Power save SDA Serial data input SCL Serial clock input OUT Current output GND Ground VCC Power supply voltage ●Block Diagram VCC VCC Power Save PS TSD & UVLO Band Gap OUT SDA SCL 2-wire serial Bus Interface & Ringing Control Pre-driver 10 OSC V/I 10 bit DAC Convertor RNF Band Gap VREF GND Figure 3. Block Diagram www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 2/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Absolute Maximum Ratings Parameter Symbol Limit Unit Power supply voltage VCC - 0.5 to + 5.5 V Power save input voltage VPS - 0.5 to + 5.5 V Control input voltage*1 VIN - 0.5 to + 5.5 V Power dissipation Pd 220*2 mW Topr - 25 to + 85 °C Tjmax 125 °C Storage temperature range Tstg - 55 to + 125 °C Output current IOUT + 200*3 mA Operating temperature range Junction temperature * 1 2 3 * * VIN is 2-wire serial interface input pins (SCL, SDA) UCSP30L1 package. Reduced by 2.2 mW/°C over 25 °C when mounted on a glass epoxy board (50 mm × 58 mm × 1.75 mm; 8 layers) Must not exceed Pd, ASO, or Tjmax of 125 °C ●Recommended Operating Ratings Parameter * Symbol Min. Typ. Max. Unit Power supply voltage VCC 2.3 3.0 4.8 V Power save input voltage VPS 0 - 4.8 V Control input voltage*1 VIN 0 - 4.8 V 2-wire serial interface frequency FCLK - - 400 kHz Output current IOUT - - 130*4 mA 1 4 * VIN is 2-wire serial interface input pins (SCL, SDA) Must not exceed Pd, ASO www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 3/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Electrical Characteristics (Unless otherwise specified Ta = 25 °C, VCC = 3.0 V) Limit Parameter Symbol Unit Conditions Min. Typ. Max. ICCST - 0 5 µA Power save pin = L = VPSL ICC - 0.6 1.0 mA Power save pin = H = VPSH 2-wire serial PS bit = 1, SCL = 400 kHz High level input voltage VPSH 1.26 - VCC V Low level input voltage VPSL 0 - 0.5 V High level input current IPSH - 10 - 10 µA VPS = 3 V Low level input current IPSL - 10 - 10 µA VPS = 0 V Power Consumption Standby current Circuit current Power Save Input (VPS = PS) Control Input (VIN = SCL, SDA) High level input voltage VINH 1.26 - VCC V Low level input voltage VINL 0 - 0.5 V Low level output voltage VINOL - - 0.4 V IIN = + 3.0 mA (SDA) High level input current IINH - 10 - 10 µA Input voltage = 0.9 x VIN Low level input current IINL - 10 - 10 µA Input voltage = 0.1 x VIN VUVLO 1.6 - 2.2 V MCLK -5 - 5 % Under Voltage Lock Out UVLO voltage Master Clock MCLK frequency MCLK = 400 kHz 10 Bit D/A Converter (for Controlling Output Current) Resolution DRES - 10 - bits Differential nonlinearity DNL -1 - 1 LSB Integral nonlinearity INL -4 - 4 LSB Output current resolution IORES - 126 - µA Per 1 DAC code step Output maximum current IOMAX 117 130 143 mA DAC_code = 0x3FF Zero code offset current IOOFS 0 1 5 mA DAC_code = 0x000 Output voltage VOUT - 150 200 mV Output current = 100 mA VOMAX - - VCC V ROUT - 1.5 2.0 Ω Output Current Performance Maximum applied voltage Output resistance www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 4/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Typical Performance Curves 4.0 3.5 Output resistance (Ω) 3.0 2.5 Ta = + 25 ℃ Ta = + 85 ℃ 2.0 1.5 1.0 Ta = - 25 ℃ 0.5 0.0 2 2.5 3 3.5 4 4.5 5 VCC (V) Figure 4. Output resistance 140 120 Ta = - 25 ℃ Output current (mA) 100 Ta = + 85 ℃ 80 60 Ta = + 25 ℃ 40 20 VCC = 3.0 V 0 0 128 256 384 512 640 768 896 1024 DAC code Figure 5. Output current vs. DAC code www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 5/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ 170 170 VCC = 3.0 V Ta = + 25 ℃ Direct 150 150 130 Displacement(µm) Displacement (µm) 130 110 110 90 70 90 70 ISRC (slew_rate = 00b) 50 ISRC (slew_rate = 01b) 50 30 30 0 20 40 Time (ms) 60 80 0 Figure 6. Displacement vs. settling time (slew_rate = 00b) 20 40 Time(ms) 170 VCC = 3.0 V Ta = + 25 ℃ Direct 150 80 VCC = 3.0 V Ta = + 25 ℃ Direct 150 130 Displacement (µm) 130 60 Figure 7. Displacement vs. settling time (slew_rate = 01b) 170 Displacement (µm) VCC = 3.0 V Ta = + 25 ℃ Direct 110 110 90 70 90 70 ISRC (slew_rate = 11b) ISRC (slew_rate = 10b) 50 50 30 30 0 20 40 Time (ms) 60 80 Figure 8. Displacement vs. settling time (slew_rate = 10b) www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 6/20 0 20 40 Time (ms) 60 80 Figure 9. Displacement vs. settling time (slew_rate = 11b) TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●2-wire serial BUS Format (Fast mode SCL = 400 kHz) Write mode（R/W = 0) S 0 Output from Master 0 0 1 1 0 0 R/W 0 0 1 1 0 0 0 Output from Slave Update A PS EN W2 W1 W0 M D9 D8 A D7 D6 D5 D4 D3 D2 D1 D0 A Read mode S 0 A PS EN W2 W1 W0 M ※ ※ A Update W (register address) Write S 0 0 0 1 1 0 0 1 A PS EN W2 W1 W0 M CD9 CD8 A CD7 CD6 CD5 CD4 CD3 CD2 CD1 CD0 nA Read S : start signal A : acknowledge P : stop signal nA : non acknowledge ※ : Don't care Register name Setting item Description R/W Read/Write mode 0 = Write mode (0x18 address), 1 = Read mode (0x19 address) PS Serial power save 0 = Driver in standby mode, 1 = Driver in operating mode EN Driver output status M Mode select 0 = Output is Hi-Z 1 = Constant current sink/sequence start M=0=ISRC mode disabled M=1=ISRC mode enabled 000b = Output current setting 001b = Parameter setting 1 W2W1W0 Register address 010b = Parameter setting 2 011b = Parameter setting 3 100b = Parameter setting 4 D9 to D0 Data bits Register data ●Register Update Timing nd PS – Register is updated during the 2 ACK response during a 3 byte 2-wire serial command rd EN – Register is updated during the 3 ACK response during a 3 byte 2-wire serial command Wx – Register is updated during the 2nd ACK response during a 3 byte 2-wire serial command rd M – Register is updated during the 3 ACK response during a 3 byte 2-wire serial command Dx – Register is updated during the 3rd ACK response during a 3 byte 2-wire serial command Note: Setting the external power save pin = VPSL (typically 0 V) will reset all 2-wire serial registers to 0 www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 7/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Register Map Address Bit Bit Name 000b D[9:0] C_DAC[9:0] Function Point C DAC code setting[9:0] D[9:8] D[7:3] rf[4:0] Resonant frequency setting[4:0] 001b D2 D[1:0] slew_rate[1:0] Slew rate speed setting[1:0] 010b D[9:0] A_DAC[9:0] Point A DAC code setting[9:0] 011b D[9:0] B_DAC[9:0] Point B DAC code setting[9:0] D[9:8] 100b D[7:5] str[2:0] Step resolution setting[2:0] D[4:0] stt[4:0] Step time setting[4:0] www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 8/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Characteristics of the SDA and SCL Bus Lines for 2-wire Serial Interface ( Ta = - 25 to +85 °C, VCC = 2.3 to 4.8 V ) STANDARD-MODE Parameter *5 FAST-MODE*5 Unit Symbol Min. Max. Min. Max. tSP 0 50 0 50 ns tHD;STA 4.0 - 0.6 - µs Low period of the SCL clock tLOW 4.7 - 1.3 - µs High period of the SCL clock tHIGH 4.0 - 0.6 - µs Set-up time for repeated START condition tSU;STA 4.7 - 0.6 - µs Data hold time tHD;DAT 0 3.45 0 0.9 µs Data set-up time tSU;DAT 250 - 100 - ns Set-up time for stop condition tSU;STO 4.0 - 0.6 - µs tBUF 4.7 - 1.3 - µs Pulse width of spikes which must be suppressed by the input filter Hold time (repeated) start condition. The first clock pulse is generated after this period. Bus free time between a stop and start condition *5 STANDARD-MODE and FAST-MODE 2-wire serial interface devices must be able to transmit or receive at the designated speed. The maximum bit transfer rates are 100 kbit/s for STANDARD-MODE devices and 400 kbit/s for FAST-MODE devices. This transfer rates is based on the maximum transfer rate. For example the bus is able to drive 100 kbit/s clocks with FAST-MODE. ●2-wire Serial Interface Timing tHIGH SCL SCL tSU : DAT tHD : STA tSU : STA tHD : DAT tLOW tSU : STO tHD : STA SDA SDA tBUF STOP BIT START BIT Figure 10. Serial Data Timing Figure 11. Start and Stop Bit Timing ●Initialization Sequence Item Symbol Min. Typ. Max. Unit Setup time for external power save pin tPS;r 0 - - µs Hold time for external power save pin tPS;f 0 - - µs 2-wire serial data start time ti2c;s 15 - - µs 2-wire serial data stop time ti2c;p 1.3 - - µs VCC Power save signal 2-wire serial data Input data tPS;r ti2c;s ti2c;p tPS;f Figure 12. Timing Between Applying Power (VCC) Until Input of Serial Data www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 9/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Power Dissipation Package : UCSP30L1 (BU64241GWZ) Power dissipation (W) 0.22 W Ambient Temperature: Ta (°C) (This value is not guaranteed value.) Figure 13. Power dissipation Pd (W) ●I/O equivalence circuit VCC SCL SDA VCC SCL VCC SDA OUT PS VCC PS www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 10/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Controlling Mechanical Ringing A voice coil motor (VCM) is an actuator technology that is intrinsically noisy due to the properties of the mechanical spring behavior. As current passes through the VCM, the lens moves and oscillates until the system reaches a steady state. The BU64241GWZ lens driver is able to control mechanical oscillations by using the integrated ISRC (intelligent slew rate control) function. ISRC is operated by setting multiple control parameters that are determined by the intrinsic characteristics of the VCM. The following steps illustrate how to best utilize ISRC to minimize mechanical oscillations. ・Step A1 – Determining the Resonant Frequency of the VCM Each VCM has a resonant frequency that can either be provided by the manufacturer or measured. The resonant frequency of an actuator determines the amount of ringing (mechanical oscillation) experienced after the lens as been moved to a target position and the driver output current held constant. To determine the resonant frequency, f0, input a target DAC code by modifying the 10 bit C_DAC[9:0] value in register W2W1W0 = 000b that will target a final lens position approximately half of the actuator’s full stroke. Take care to not apply too much current so that the lens does not hit the mechanical end of the actuator as this will show an incorrect resonant period. In order to start movement of the lens to the DAC code that was set in C_DAC[9:0], the EN bit must be set to 1. T Displacement (µm) ? ? ? ? µm? 0 Time (ms) Time (ms) Figure 14. Actuator Displacement Waveform (ISRC Disabled) The resonant frequency (Hz) of the actuator can be calculated with Equation 1 using the resonant period observed in Figure 14. f0 = (T)-1 Equation1. Resonant Frequency vs. Time Period Relationship After calculating the correct resonant frequency, program the closest value in the W2W1W0 = 001b register using the 5 bit rf[4:0] values from Table 1. When calculating the resonant frequency take care that different actuator samples’ resonant frequencies might vary slightly and that the frequency tolerance should be taken into consideration when selecting the correct driver resonant frequency value. Table 1. f0 Settings (rf[4:0]) rf[4:0] f0 rf[4:0] f0 rf[4:0] f0 rf[4:0] f0 00000 - 01000 85 Hz 10000 125 Hz 11000 - 00001 50 Hz 01001 90 Hz 10001 130 Hz 11001 - 00010 55 Hz 01010 95 Hz 10010 135 Hz 11010 - 00011 60 Hz 01011 100 Hz 10011 140 Hz 11011 - 00100 65 Hz 01100 105 Hz 10100 145 Hz 11100 - 00101 70 Hz 01101 110 Hz 10101 150 Hz 11101 - 00110 75 Hz 01110 115 Hz 10110 - 11110 - 00111 80 Hz 01111 120 Hz 10111 - 11111 - www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 11/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ・Step A2 – Selecting the Autofocus Algorithm’s Target DAC Codes The ISRC algorithm is a proprietary technology developed to limit the ringing of an actuator by predicting the magnitude of ringing created by an actuator and intelligently controlling the output signal of the driver to minimize the ringing effect. Due to the ringing control behavior of ISRC, it is unable to operate properly unless the lens is floating (lens lifted off of the mechanical end of the actuator). As such the ringing control behavior is broken into three separate operational areas in order to provide the most optimally controlled autofocus algorithm. Direct Mode ISRC Mode Step Mode Displacement (µm) C Displacement (µm) B A 0 DAC code A: lens displacement = 0 µm B: all lenses floating C: final lens position Figure 15. Lens Displacement vs. DAC Code Figure 15 illustrates the different operational modes that control the autofocus algorithm. Due to ISRC requiring a floating lens, points A and B need to bet set in order to create a floating condition. Point A corresponds to the maximum amount of current that can be applied to all VCM units without floating the lens. Point B corresponds to the minimum amount of current that can be applied to the VCM so that all actuator units are floating. It should be noted that the target DAC codes could vary between different actuator units and that sufficient evaluation should be performed before selecting the point A and B target DAC codes. Point C is the final lens target position determined by the level of focus required for the image capture. The actuator manufacturer should be able to provide the required current for points A and B, however it is possible to test these points by slowly increasing the 10 bit value of C_DAC[9:0] and measuring the lens movement using a laser displacement meter or some other device to measure lens displacement. www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 12/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Controlling the Driver After following steps A1 and A2 to characterize the VCM performance, the following steps should be followed in order to properly control the driver settings for optimized autofocus performance. ・Step B1 – Setting Point A, B, and C DAC Codes Points A, B, and C are defined by 10 bit DAC codes set with the following registers: Location W2W1W0 Register DAC Code Location Description Point C 000b C_DAC[9:0] Final lens position before image capture Point A 010b A_DAC[9:0] Maximum output current without floating the lens Point B 011b B_DAC[9:0] Minimum output current required to float the lens ・Step B2 – Controlling Direct Mode Direct mode is when the driver outputs the desired amount of output current with no output current control. The time in which the lens reaches the position that corresponds to the amount of output current set by the 10 bit DAC code is ideally instant, ignoring the ringing effects. If the driver is set so that the lens is moved from a resting position to point C with direct mode, ringing and settling time will be at a maximum. Direct mode is used either when M = 0 or when M = 1 and the present DAC code is less than the DAC code of point A. M = 0 = ISRC mode disabled When ISRC mode is disabled by setting the M bit equal to 0, the lens will traverse to the DAC code set for point C when the EN bit is set equal to 1. M = 1 = ISRC mode enabled The driver automatically uses direct mode if the present DAC code is less than the target DAC code corresponding to point A. Therefore during ISRC operation when the autofocus sequence has been started by setting the EN bit equal to 1, the driver will automatically decide to use direct mode to output current up to point A and then switch to step mode before continuing the autofocus sequence. www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 13/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ・Step B3 – Controlling Step Mode Step mode is the control period in which the lens is moved by small output current steps. During step mode it is possible to control the step resolution and step time in order to generate just enough output current to float the lens with minimal ringing effects. Ringing can be better controlled by choosing a large value for the step time and a small value for the step resolution with the trade off of a greater settling time. The step time and step resolution should be chosen depending on the acceptable system limits of ringing vs. settling time. Step mode is used when M = 1 and the present DAC code is in between point A and point B. Typically this mode is only used during ISRC operation between point A and B, however it is possible to move the lens to point C using only step mode if point C is set such that point C is only 1 DAC code greater than point B. Step mode is controlled by the 5 bit step time, stt[4:0], and 3 bit step resolution, str[2:0], values stored in register W2W1W0 = 100b. Table 2. Step Time Settings stt[4:0] Step Time stt[4:0] Step Time stt[4:0] Step Time stt[4:0] Step Time 00000 - 01000 400 µs 10000 800 µs 11000 1200 µs 00001 50 µs 01001 450 µs 10001 850 µs 11001 1250 µs 00010 100 µs 01010 500 µs 10010 900 µs 11010 1300 µs 00011 150 µs 01011 550 µs 10011 950 µs 11011 1350 µs 00100 200 µs 01100 600 µs 10100 1000 µs 11100 1400 µs 00101 250 µs 01101 650 µs 10101 1050 µs 11101 1450 µs 00110 300 µs 01110 700 µs 10110 1100 µs 11110 1500 µs 00111 350 µs 01111 750 µs 10111 1150 µs 11111 1550 µs str[2:0] Step Resolution str[2:0] Step Resolution 000 - 010 2 LSB 100 4 LSB 110 6 LSB 001 1 LSB 011 3 LSB 101 5 LSB 111 7 LSB www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 Table 3. Step Resolution Settings Step Step str[2:0] str[2:0] Resolution Resolution 14/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ・Step B4 – Controlling ISRC Mode ISRC mode is the control period in which the lens is already floating and the driver smoothly moves the lens based on the proprietary behavior of the ISRC algorithm. ISRC operation keeps ringing at a minimum while achieving the fastest possible settling time based on the ISRC operational conditions. ISRC mode is used when M = 1 and the present DAC code is greater than the DAC code for point B. If the target DAC code for point C is set so that the value is too large and will cause excess ringing, the point C DAC code is automatically updated with a driver pre-determined value to minimize the ringing effect. When M = 1, the driver will automatically switch between direct mode, step mode, and ISRC mode when the point A, B, and C DAC code conditions are met. The condition for this automatic transitioning to occur is when the register values for point A, point B, point C, step time, and step resolution are all set to values other than 0 and then the sequence will start when the EN bit is set equal to 1. DAC code C B ISRC DAC codes* A Step mode Direct mode ISRC mode * ISRC DAC codes the details of ISRC operation are proprietary 0 Time (ms) Start sequence Displacement (µm) Figure 16. Three Modes Sequential Operation (Shown as DAC Codes) 0 Time (ms) Sequence start point Figure 17. Three Modes Sequential Operation (Shown as Lens Displacement) www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 15/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ・Step B5 – Controlling the ISRC Settling Time The settling time of an actuator is the time it takes for ringing to cease. The BU64241GWZ is able to control the settling time by modifying the slew rate speed parameter, however care must be taken to balance settling time vs. acceptable ringing levels. By increasing the slew rate speed there is the possibility to decrease the settling time but the ability to control ringing is also decreased. Likewise if less ringing is desired then there is a possibility to reduce the ringing level by using a slower slew rate speed setting at the cost of a longer settling time. The slew rate speed can be set by modifying the 2 bit slew_rate[1:0] value in register W2W1W0 = 001b. Figure 18 shows the relationship of displacement vs. settling time. 移動量 〔um〕 Displacement (µm) slew_rate [1:0] = 11b Slew_rate〔1:0〕=2'b11 0 slew_rate [1:0] = 10b Slew_rate〔1:0〕=2'b10 Slew_rate〔1:0〕=2'b01 slew_rate [1:0] = 01b Slew_rate〔1:0〕=2'b00 slew_rate [1:0] = 00b T_DAC〔9:0〕変更 C_DAC [9:0] update TimeTime (ms) 〔ms〕 Figure 18. Displacement vs. Settling Time slew_rate[1:0] Slew Rate Speed 00 Slowest Table 4. Slew Rate Speed Settings Slew Rate slew_rate[1:0] slew_rate[1:0] Speed www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 01 Slow 10 16/20 Slew Rate Speed slew_rate[1:0] Slew Rate Speed Fast 11 Fastest TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ・Step B6 – DAC Code Update Timing Considerations Settling time is controlled by the resonant frequency of the actuator and the driver’s slew rate speed setting. Depending on the combination of these parameters, the settling time can be such that updating point C with a new DAC code before the lens has settled at the original point C DAC code can adversely affect the settling time due to increased ringing effects. Utilize the slew rate speed parameter in order to modify the settling time so that any updates to the point C DAC code do not occur before the lens has settled. Please review the following example based on an actuator with a resonant frequency of 100 Hz: Table 5. Relationship Between Slew Rate Speed and Settling Time Based on a 100 Hz Actuator f0 slew_rate[1:0] Settling Time 00 52 ms 01 42 ms 10 26 ms 11 18 ms 100 Hz In this example the settling time of the actuator can vary by up to ± 5 % due to the internal oscillator (MCLK) having a variance of ± 5%. The settling time has a proportionally inverse relationship to the resonant frequency and therefore the settling time can be estimated as: Table 6. Relationship Between Slew Rate Speed and Settling Time Based on a General Resonant Frequency f0’ f0’ slew_rate[1:0] Settling Time 00 52 * (100 / f0’) ms 01 42 * (100 / f0’) ms 10 26 * (100 / f0’) ms 11 18 * (100 / f0’) ms f0’ Hz Note that the orientation of the camera module can affect the settling time due to the influence of gravity on the lens. ・Step C1 – Power Save Operation The BU64241GWZ can be set to enter power save mode either by setting the external power save pin = VPSL (typically 0 V) or by setting the 2-wire serial PS bit = 0. It is recommended to use the external power save pin method since this will disable the internal MCLK to achieve lower power consumption while in standby mode. Please note that setting the external power save pin = VPSL will reset all 2-wire serial registers to 0. www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 17/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Operational Notes (1) Absolute maximum ratings Use of the IC in excess of absolute maximum ratings such as the applied voltage or operating temperature range (Topr) may result in IC damage. Assumptions should not be made regarding the state of the IC (short mode or open mode) when such damage is incurred. The implementation of a physical safety measure such as a fuse should be considered when there is use of the IC in a special mode where it’s anticipated that the absolute maximum ratings may be exceeded. (2) Power supply lines Regenerated current may flow as a result of the motor's back electromotive force. Insert capacitors between the power supply and ground pins to serve as a route for regenerated current. Determine the capacitance based on of all the characteristics of an electrolytic capacitor due to the electrolytic capacitor possibly losing some capacitance at low temperatures. If the connected power supply does not have sufficient current absorption capacity, regenerative current will cause the voltage on the power supply line to rise, which combined with the product and its peripheral circuitry may exceed the absolute maximum ratings. It is recommended to implement a physical safety measure such as the insertion of a voltage clamp diode between the power supply and GND pins. (3) Heat dissipation Use a thermal design that allows for a sufficient margin regarding the power dissipation (Pd) during actual operating conditions. (4) Use in strong magnetic fields Use caution when using the IC in the presence of a strong magnetic field as doing so may cause the IC to malfunction. (5) ASO When using the IC, set the output transistor for the motor so that it does not exceed absolute maximum ratings or ASO. (6) Thermal shutdown circuit This IC incorporates a TSD (thermal shutdown) circuit. If the temperature of the chip reaches the below temperature, the motor coil output will be opened. The thermal shutdown circuit (TSD circuit) is designed only to shut off the IC to prevent runaway thermal operation. It is not designed to protect the IC or to guarantee its operation. Do not continue to use the IC after use of the TSD feature or use the IC in an environment where the its assumed that the TSD feature will be used. TSD ON temperature [°C] Hysteresis temperature [°C] (Typ.) (Typ.) 150 20 (7) Ground Wiring Pattern Ensure a minimum GND pin potential in all operating conditions. When using GND patterns for both small signal and large currents, it is recommended to isolate the two ground patterns by placing a single ground point at the application's reference point. This will help to alleviate noise in the small signal ground voltage due to noise created by the ground pattern wiring resistance for large current blocks. Be careful not to change the GND wiring pattern of any external components. (8) Power Save (PS) terminal PS holds the reset function on logic concurrently. Please release PS after the start-up of VCC. Reset is not normally done when VCC is short-circuited to PS and it uses it, and there is a possibility of malfunctions. www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 18/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Ordering Part Number B U 6 4 2 4 1 Part Number G W Z E2 Package GWZ: UCSP30L1 Packaging and forming specification E2: Embossed tape and reel ●Physical Dimension Tape and Reel Information UCSP30L1 (BU64241GWZ) Lot No. 1PIN MARK <Packing specification> 0.06 1.30±0.03 0.06 0.33MAX 0.77±0.03 BX Tape Embossed carrier tape Quantity 6,000 pcs / reel Direction of feed E2 (See neighboring image) S 1234 1234 1234 1234 1234 S 1pin Direction of feed 0.185×0.05 Reel 6-φ0.20±0.05 A 0.05 A B 1234 B 0.4 B A 1 2 3 0.25±0.05 P=0.4×2 (Unit: mm) *Order quantity needs to be multiple of the minimum quantity. ●Marking Diagram(TOP VIEW) UCSP30L1 (BU64241GWZ) Product ProductName Name Lot No. Lot No. 1PIN 1PIN MARK MARK BX ABX www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 19/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet BU64241GWZ ●Revision History Date Revision Changes 15.Oct.2012 001 New Release 11.Apr.2013 002 Add information about “BU64243GWZ”. 31.May.2013 003 Delete information about “BU64240GWZ”. 01.Jul.2013 004 Delete information about “BU64243GWZ”. www.rohm.com © 2012 ROHM Co., Ltd. All rights reserved. TSZ22111・15・001 20/20 TSZ02201-0H2H0B600460-1-2 01. Jul. 2013 Rev.004 Datasheet Notice Precaution on using ROHM Products 1. Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment, OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you (Note 1) , transport intend to use our Products in devices requiring extremely high reliability (such as medical equipment equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance. Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific Applications. (Note1) Medical Equipment Classification of the Specific Applications JAPAN USA EU CHINA CLASSⅢ CLASSⅡb CLASSⅢ CLASSⅢ CLASSⅣ CLASSⅢ 2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which a failure or malfunction of our Products may cause. The following are examples of safety measures: [a] Installation of protection circuits or other protective devices to improve system safety [b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure 3. Our Products are designed and manufactured for use under standard conditions and not under any special or extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any special or extraordinary environments or conditions. If you intend to use our Products under any special or extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of product performance, reliability, etc, prior to use, must be necessary: [a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents [b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust [c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2 [d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves [e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items [f] Sealing or coating our Products with resin or other coating materials [g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning residue after soldering [h] Use of the Products in places subject to dew condensation 4. The Products are not subject to radiation-proof design. 5. Please verify and confirm characteristics of the final or mounted products in using the Products. 6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied, confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect product performance and reliability. 7. De-rate Power Dissipation (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actual ambient temperature. 8. Confirm that operation temperature is within the specified range described in the product specification. 9. ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in this document. Precaution for Mounting / Circuit board design 1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product performance and reliability. 2. In principle, the reflow soldering method must be used; if flow soldering method is preferred, please consult with the ROHM representative in advance. For details, please refer to ROHM Mounting specification Notice - GE © 2014 ROHM Co., Ltd. All rights reserved. Rev.002 Datasheet Precautions Regarding Application Examples and External Circuits 1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the characteristics of the Products and external components, including transient characteristics, as well as static characteristics. 2. You agree that application notes, reference designs, and associated data and information contained in this document are presented only as guidance for Products use. Therefore, in case you use such information, you are solely responsible for it and you must exercise your own independent verification and judgment in the use of such information contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of such information. Precaution for Electrostatic This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron, isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control). Precaution for Storage / Transportation 1. Product performance and soldered connections may deteriorate if the Products are stored in the places where: [a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2 [b] the temperature or humidity exceeds those recommended by ROHM [c] the Products are exposed to direct sunshine or condensation [d] the Products are exposed to high Electrostatic 2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time period may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is exceeding the recommended storage time period. 3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads may occur due to excessive stress applied when dropping of a carton. 4. Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of which storage time is exceeding the recommended storage time period. Precaution for Product Label QR code printed on ROHM Products label is for ROHM’s internal use only. Precaution for Disposition When disposing Products please dispose them properly using an authorized industry waste company. Precaution for Foreign Exchange and Foreign Trade act Since our Products might fall under controlled goods prescribed by the applicable foreign exchange and foreign trade act, please consult with ROHM representative in case of export. Precaution Regarding Intellectual Property Rights 1. All information and data including but not limited to application example contained in this document is for reference only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any other rights of any third party regarding such information or data. ROHM shall not be in any way responsible or liable for infringement of any intellectual property rights or other damages arising from use of such information or data.: 2. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any third parties with respect to the information contained in this document. Other Precaution 1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM. 2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written consent of ROHM. 3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the Products or this document for any military purposes, including but not limited to, the development of mass-destruction weapons. 4. The proper names of companies or products described in this document are trademarks or registered trademarks of ROHM, its affiliated companies or third parties. Notice - GE © 2014 ROHM Co., Ltd. All rights reserved. Rev.002 Datasheet General Precaution 1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents. ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny ROHM’s Products against warning, caution or note contained in this document. 2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s representative. 3. The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or concerning such information. Notice – WE © 2014 ROHM Co., Ltd. All rights reserved. Rev.001 Datasheet BU64241GWZ - Web Page Buy Distribution Inventory Part Number Package Unit Quantity Minimum Package Quantity Packing Type Constitution Materials List RoHS BU64241GWZ UCSP30L1 6000 6000 Taping inquiry Yes