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CMT-TIT8243A

CMT-TIT8243A

  • 厂商:

    CISSOID

  • 封装:

    模块

  • 描述:

    MOS GATE DRIVER 62MM 1200V SIC

  • 数据手册
  • 价格&库存
CMT-TIT8243A 数据手册
The Leader in High Temperature Semiconductor Solutions 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Version: 1.4 (see note 1) Features • Designed to drive 62mm 300A SiC MOSFET Power Modules • Gate driving voltages: +20V/-5V (3% precision) • Board size: 69 mm * 116 mm • Low inductance gate loop design • Operating temperature: -40°C to 125°C • Single power supply: 12V-18V • Bus voltage:1200V/1700V max • Open-drain fault output • Isolation: 3600VAC @50Hz (1min) • Under voltage lockout (UVLO) • 14mm Creepage/12mm clearance • On-board optional non-overlap generation (via jumper) • RS422 PWM input interface • > 50kV/µs dV/dt immunity • Low parasitic capacitance between primary and high-side: 10pF • Switching frequency up to 100kHz • Delay (PWM to VOUT): 200ns typ. • FET Gate rise/fall time:40ns typ. • Anti-overlap protection (on PWM inputs) • Glitch suppressor on PWM inputs • Active Miller Clamping (AMC) • Desaturation protection • Gate-Source short-circuit protection Note1: Please always refer to the latest datasheet version available at: http://www.cissoid.com/files/files/products/titan/CMT-TIT8243.pdf PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 1 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Ordering Information Product Name CMT-TIT8243 CMT-TIT8244 Ordering Reference CMT-TIT8243A CMT-TIT8244A Voltage 1200V 1700V Marking CMT-TIT8243A CMT-TIT8244A High level block diagram CMT8243/8244 D_HS DESAT VH_HS VREF VH_HS VREF UVLO VL_HS HS FAULTH RGPH UVLO PWMHP/PWMHN Primary logic Secondary Logic Isolated Data Transceiver G_HS DESAT RGNH LS VH_HS VIN S_HS VL_HS S_HS DC/DC PWM PWM PWM Controller CONTROLLER VL_HS VH_LS D_LS S_LS DESAT VH_LS VREF GND VL_LS VH_LS VREF UVLO VL_LS HS RGPL UVLO G_LS FAULTL PWMLP/PWMLN DESAT Primary logic LS Isolated Data Transceiver PUBLIC Doc. PDS-181985 V1.4 RGNL Secondary Logic WWW.CISSOID.COM VL_LS S_LS 8-Jan-21 2 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet IO Description2 Pin Name Pin ID Pin Description PMWLN 1 PWMHN 2 PMWLP 3 PWMHP 4 FAULTL 5 Low-side fault FAULTH 6 High-side fault GND 7 Ground VIN 8 Positive supply Negative Low-side PWM control signal Negative High-side PWM control signal Positive Low-side PWM control signal Positive High-side PWM control signal PE Chassis connection D_HS High-side drain sense signal G_HS High-side gate signal S_HS High-side source sense signal S_LS Low-side source sense signal G_LS Low-side gate signal D_LS Low-side drain sense signal VIN GND PWMHP/PWMHN FAULTH PWMLP/PWMLN FAULTL PE 2 Positive supply All other power supplies for driving the gate of the FETs are internally generated by the on-board DC-DC converter Ground Reference ground for the supply and the digital IOs. Input control signals for the high-side driver These signals control the state of the high-side FET. When in Local mode (selection by jumper), those signals control both low-side and high-side channels in opposite states with some internally defined nonoverlapping delay. High-side channel fault output (open drain) This signal combines: The high-side secondary Desaturation fault The high-side secondary UVLO fault The primary fault. In case of fault, FAULTH is set to “0V” for a duration equal to internal timer defined at board level. Input control signal for the low-side driver The signal controls the state of the low-side FET. When in Local mode (selection by jumper), those signals have no effect, the low-side FET being control by PWMH and the local non-overlap function. Low-side channel fault output (open drain) This signal combines: The low-side secondary Desaturation fault The low-side secondary UVLO fault The primary fault. In case of fault, FAULTL is set to “0V” for a duration equal to internal timer defined at board level. Chassis connection A 1000V 1nF capacitance is connected between PE and each of the pins 1 to 8 Refer to section Mechanical characteristics page 13 for more details on connector pinout PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 3 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Absolute Maximum Ratings Stressing the board above these absolute maximum ratings could present permanent damage. Exposure to this maximum rating for extended periods may affect the board reliability. These ratings are considered individually (not in combination). If not specified, voltages are related to GND Parameter (VIN-GND) Voltage transient on S_HS Voltage on D_HS, D_LS Output power per gate Steady Operating Temperature (no airflow) Storage Temperature Min. -0.5 -40 -40 PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM Max. 18 100 1200/1700 2.375 125 125 Units V kV/µs V W °C °C 8-Jan-21 4 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Electrical Characteristics Unless otherwise stated: Tj=25°C. Bold underlined values indicate values valid over the whole temperature range (-40°C < Ta < +125°C). Parameter Condition Min Typ Max Units External Power Supply External Power Supply VIN IAVG(VIN) IAVG(VIN) max Parameter Versus GND 12 VIN=12V, no PWM No fault situation Direct Mode Load: CREE WOLFSPEEDCAS300M12BM2 VIN=12V; 20 kHz; 50% DutyCycle No fault situation Direct Mode Load: CREE WOLFSPEEDCAS300M12BM2 VIN=12V Condition 18 103 mA 220 mA 500 Min V Typ Max mA Units Isolation Inter channel Isolation IH2L Low-side channel isolation IL2P High-side channel isolation IH2P Maximum supported dV/dt Parasitic capacitance Creepage Clearance S_HS to S_LS (50Hz, 1min) S_LS to GND (50Hz, 1min) S_HS to GND (50Hz, 1min) S_HS to S_LS S_HS to GND (guaranteed by design) Between High-Side and Primary Primary to any secondary Between secondaries Primary to any secondary Between secondaries PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 3.6 kVrms 3.6 kVrms 3.6 kVrms 50 kV/µs 14 10 pF mm 12 mm 8-Jan-21 5 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Electrical Characteristics Unless otherwise stated: Tj=25°C. Bold underlined values indicate values valid over the whole temperature range (-40°C < Ta < +125°C). Parameter Condition Min Typ Max Units PWML/PWMH inputs Common mode input level -6 Differential input high-threshold voltage Diff(PWMxP,PWMxN) Differential input low-threshold voltage Differential input impedance Diff(PWMxP,PWMxN) Minimum pulse width Anti-overlap duration Propagation delay (PWML/PWMH →G_LS/G_HS) (50% to 10%) Non-overlap duration3 200 mV Ω 50 ns 200 ns 100 100 0 Direct Mode Default settings for glitch suppressor and anti-overlap prevention Local Mode (configurable via capacitance Cnovd) V mV -50 Configurable via capacitances Cglil (on PWML) and Cglih (on PWMH) Direct Mode Configurable via capacitances Cnovl (on PWML) and Cnovh (on PWMH) Maximum frequency Duty cycle +10 200 kHz % 170 ns 480 ns FAULTL/FAULTH open drain outputs On resistance Fault local latching time (at Primary or at Secondary) Parameter G_LS/G_HS Gate driver outputs High level Low level Maximum average output load current Peak output current Rgate_on Rgate_off Gate-Source resistance Active Miller Clamp (AMC) transistor Rdson Applies to FAULTL/FAULTH 25 14 Condition Rgate_on=Rgate_off= 0Ω Ω ms Min Typ Max Units 19.4 -5.2 20 -5 20.6 -4.8 95 1.8 1.8 100 V V mA A Ω Ω kΩ 33 mΩ 10 D_LS/D_HS Desaturation Monitoring inputs Voltage range CMT8243 CMT8244 0 0 Parameter Condition Min Typ Under-voltage Lockout on primary supply (VIN) (UVLO_P) UVLO_P High Threshold 9.75 UVLO_P Low Threshold 8.2 Under-voltage Lockout on secondary supplies (VDD_L-VSS_L)/ (VDD_H-VSS_H) (UVLO_S) UVLO_S High Threshold 22.7 UVLO_S Low Threshold 20.5 Desaturation detection Threshold on D_LS/D_HS D_LS/D_HS wrt to S_LS/S_HS 4.34 (configurable via resistance Rdesatx) Configurable via capacitance Cdesatdx Desaturation Blanking time 1 (68pF Cdesatdx installed) Delay from desaturation detection to 350 G_LS/G_HS starting to turn off G_LS/G_HS turn-off time after desatura- From 20V to 0V tion detection Load : CREE WOLFSPEED1 CAS300M12BM2 Soft Shutdown (SSD) resistor 20 Start-up Start-up time 30 3 1200 1700 V V Max Units V V V V V µs ns µs Ω ms Non-overlap delay includes glitch suppressor delay; 10pF parasitic capacitance to be added to Cnovd PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 6 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Circuit Functionality Description Under-Voltage Lockout (UVLO) CMT-TIT8243/8244 board is a Half-Bridge gate driver board meant to drive 62mm SiC power modules (typically CREE WOLFSPEED CAS300M12BM2). CMT-TIT8243/8244 board monitors constantly: - Its main features are: - - - - - - - - - Isolated data transmission (robust to high dV/dt) (data and fault) on both high and low side channels Adjustable fault timer with automatic restart Safe start-up sequence through monitoring of the main supply (UVLO) and of the voltage regulators output (through Power-Good function) Permanent and programmable Under-Voltage Lockout (UVLO) monitoring on external and internally generated power switch supplies Desaturation detection function with programmable blanking time and threshold protecting power switches in case of abnormal current levels Soft-Shutdown transistor and control performing power device graceful shutdown in case of fault and so preventing too high dI/dt in the power stage Active Miller Clamping (AMC) Flyback DC-DC convertor with cycleby-cycle current limit for short circuit protection High-precision (typ 3%) high-level gate voltage generation Differential RS422 PWM inputs Open-drain low-ohmic (typ. 25Ω) FAULT output Support of 2 separate incoming PWM channels and of locally generated non-overlapped PWM signals Configurable 50ns (typ) spike filter on incoming PWM signal for enhanced noise robustness Configurable 200ns (typ) anti-overlap protection on incoming PWM signals Gate-2-Source short-circuit protection At primary side, the monitored power supply is “VIN-GND”; to avoid oscillation when (VIN-GND) is close to the UVLO threshold, a hysteresis is implemented. At each secondary side, the monitored power supply is “VDD_L-VSS_L”/ “VDD_H-VSS_H”; to avoid oscillation when (VDD_x-VSS_x) is close to the UVLO threshold, a hysteresis is implemented. Refer to the chapter Fault Management/LED status for details about fault behavior and management. On-board power supplies The on-board isolated power supply is a regulated flyback DC-DC converter providing both channels with the positive and negative supply voltages required to drive the power FETs. It offers high voltage isolation between the channels, high dV/dt sustainability and very low parasitic capacitance. Cycle-by-cycle current monitoring at primary side is implemented to protect the board against short-circuit. High accuracy (typ 3%) is achieved on all secondary positive supplies. Interface towards controller PWM inputs PWML and PWMH input interface is based on RS422 differential receivers to increase noise immunity on those incoming signals. are high impedance inputs. CMT-TIT8243/8244 board implements 2 protection functions on the PWM data paths: PUBLIC Doc. PDS-181985 V1.4 VIN power supply High-side secondary supplies (typ +20V/-5V) Low-side secondary supplies (typ +20V/-5V) WWW.CISSOID.COM 8-Jan-21 7 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet - Anti-glitch: any negative or positive glitch on PWML/PMWH signals smaller than a programmed value is ignored by the board; this is increasing immunity of incoming signals against external noise; the signals are delayed by the corresponding anti-glitch time tMINPW (ns)= 0.5* [CGLIx (pF)] - Anti-overlap: this circuit prevents PWML and PMWH to be active at the same time by forcing an internal nonoverlap time; if PWML and PWMH are not overlapping by more than the internally programmed time, they are not delayed internally. If PWML and PWMH are active for a long period, both gate outputs are forced to zero until one of the inputs goes to zero. tNOVP (ns)= 0.5* [CNOVx (pF)] The sensing of the power device drain voltage is performed through a high voltage sensing diode whom cathode is connected to the power switch drain and whom anode is connected to a current source (typ 2mA) and a sensing circuit. The desaturation threshold (on D_LS/D_HS nodes) is configured by onboard resistors and can be tuned according to the table below. Rdesat value 0KΩ 5KΩ 10KΩ (default) 15KΩ 20KΩ 30KΩ Desat threshold (V) 25°C 125°C 0.93 1.22 2.35 2.62 3.77 4.02 5.18 5.42 6.6 6.82 9.42 9.62 At system level, the de-saturation detection should only be taken into account after a defined time following the low-to-high transition on the power device gate. This “blanking” time tDESAT_D is implemented and adjusted by an on-board capacitor CDESATD (68pF installed) and can be calculated as follows: tDESATD (ns)= 14* [CDESATD (pF) + 7] FAULT outputs The output buffers operate as an opendrain driver with a low Ron resistance (typ. 25Ω), enabling the use of low value pull-up resistance for increased noise immunity. Isolated data transmission CMT-TIT8243/8244 board uses integrated digital isolators. Those devices provide isolation, immunity against high dV/dt and low parasitic capacitance. In case no power supply is present at the secondary side, a fault is generated at the primary side. Desaturation detection The purpose of the desaturation function is to detect that the voltage at the drain of the power switch, in “ON” state, is higher than a given threshold. This informs the logic part of the system about possible damage of the power arm (e.g. a short circuit at the arm level leading to an overcurrent in the power switch). If after tDESAT_D time, the DESAT comparator output indicates that D_LS/D_LS level is higher than the programmed threshold value, an internal DESAT fault is generated. Refer to the chapter Fault Management/LED status for details about fault behavior and management. When the desaturation fault is detected, the power module gate is gracefully discharged thanks to the Soft-Shutdown circuit to avoid high dI/dt at power module turn-off To sense the drain voltage, fast-on connectors are present on the board (see them marked D_HS, D_LS on picture below). For D_LS signal sensing, instead of a wire towards the power module, a wire between D_LS net and S_HS net (see wire in red on picture below) can be added by the customer; this can simplify the wiring towards the power module. PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 8 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Active Miller Clamping In case of high positive dV/dt and despite the negative drive of the power module gate, a parasitic turn-on of the gate could take place, inducing shoot-through current on the power arm. To prevent this, CMT-TIT8243/8244 board implements an Active Miller Clamping function by bypassing the gate resistance with a low ohmic path (implemented with a transistor) when the gate is driven negative. This transistor also helps to limit the amplitude of negative kick on the power module gate in case of negative dV/dt. Fault Management/LED status At primary side, fault is generated by any of those situations: - Main power supply (VIN) is below the UVLO threshold Primary linear voltage regulator (generating the 5V output required by the on-board logic) is below the internal Power Good level Those faults are internally combined to generate a unique fault signal. This internal fault signal is latched for 14msec. While the fault is latched: - Both FAULTL/FAULTH pins are tied to “0” Both power switches are turned off On board DC-DC converter is off After the predefined latch time period, CMT-TIT8243/8244 board will attempt to return to normal operation: - If the fault is still present, CMTTIT8243/8244 board will stay in the fault state till the fault disappears - If the fault disappeared (e.g. temporary UVLO situation), CMTTIT8243/8244 board will go out of FAULT state and return to normal operation (DC-DC converter turned on and data paths active); still, on the PWM path, transition to normal operation will happen on the next positive edge of the incoming PWM signal. The primary fault state is combined with the faults returned by the secondary devices according to Table 1. Prim fault Lowside fault No Yes No Yes Yes or No No No No No Yes FAULTL FAULTH No fault Fault No fault Fault Fault No fault No fault Fault Fault Fault Table 1: FAULT aggregation table At each of the secondary side, fault is generated by any of those situations: - - Power supply is below the UVLO threshold Secondary voltage regulator (5V) output voltage is below the PowerGood threshold Desaturation situation is detected by the DESAT comparator Those faults are internally combined to generate a unique fault signal. This internal fault signal is latched for 14msec. While the fault is latched, the gate driver is turned off. At the transition between “no fault” and “fault” situation, the gate driver circuit is gracefully shut down (Soft ShutDown). After the predefined latch time period, the gate driver circuit returns to normal operation: - - If the fault is still present, the gate driver is kept turned off till the fault disappears If the fault disappeared (e.g. temporary UVLO situation), normal operation will resume on the next positive edge of incoming PWM signal 2 LEDs are present on the CMTTIT8243/8244 board and are reflecting board status as follows: State No supply Operational Primary or secondary fault PUBLIC Doc. PDS-181985 V1.4 Highside fault No No Yes Yes Yes or No WWW.CISSOID.COM LED1 State Off On On Color None Green Green LED2 State Off Off On Color None None Red 8-Jan-21 9 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Modes of operation Board power dissipation CMT-TIT8243/8244 board offers 2 modes of operation: Current consumption of the CMTTIT8243/8244 board (Vin=12V) can be computed as follows: - - Direct Mode: PWML and PWMH are generated independently outside CMT-TIT8243/8244 board. In this case, proper non overlapping must be generated externally. Local Mode: PWML and PWMH are generated out of one input signal (PWMH) and proper non overlapping timing is managed locally on the CMT-TIT8243/8244 board (cfr Figure 1) Iin = 103mAtyp + Act * (0.26 + 0.0055 * Qg ) * Fs Where: - - PWMH - NGH NGL tNOV_D tNOV_D Figure 1: Local Mode operation The choice between those 2 modes of operation is made via the jumper JP1. When in Local Mode, an on-board capacitance (Cnovd) defines the non-overlap delay according to following formula: Iin is the input current (in mA) (wrt to Vin = 12V) Act is a Boolean (0: PWML/PWMH = 0, 1: PWM_L/PWM_H alternating at Fs frequency) Gg: Total gate charge of one power transistor (in nC) Fs: Switching frequency (in kHz) The duty cycle of the PWML/PWMH signals has almost no influence on the current consumption of the CMTTIT8243/8244 board (assuming PWML and PWMH duty cycles are complementary). To stay within specifications of the internal secondary voltages, the maximum average Iin current should be 500 mA (for Vin =12V). tNOV_D (ns)=5.5 * CNOVD (pF) PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 10 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Dynamic behavior Figure 2 illustrates the CMT-TIT8243/8244 low-side driver dynamic behavior in normal operation and fault conditions. Normal Case PWML 1 Fault UVLO Normal Case 6 2 7 G_LS UVLO 3 FAULT Internal timer 4 Normal Case PWML 1 tFLTD 5 FAULT Desat Normal Case 3 7 8 G_LS D_LS tDESATD DESAT BLANK tDESATD FAULT 2 4 Internal timer 5 tFLTD 6 Figure 2: Timing diagram CMT-TIT8243/8244 low-side driver behaviour In Normal operation on PWML rising edge (1), rising edge is generated on G_LS (after propagation delay through CMT-TIT8243/8244 board). After rising edge on G_LS, low-side power module is turned ON and midpoint node is going to “0” state (voltage equals to Ron * current flowing through the power device). D_LS node is also pulled down and after blanking time (tDESAT_D), no desaturation fault is detected and FAULTL remains high. on PWML falling edge (2), falling edge is generated on G_LS (after propagation delay through CMT-TIT8243/8244 board) After falling edge on G_LS, the low-side power device is turned OFF. After rising edge on G_LS, low-side power module is turned ON; because of a desaturation fault, D_LS node does not reach its normal “0” level. Thanks to the DESAT comparator, CMT-TIT8243/8244 board detects this fault situation and turns off gracefully G_LS. Power device is turned off. FAULTL signal is pulled down. Fault is cleared after fault timer expiry. In UVLO fault situation UVLO status is monitored inside the secondary devices (and inside primary device as well; for clarity, only secondary UVLO situation is described here). When UVLO comparator (5) detects an under-voltage situation, G_LS is gracefully shut down FAULTL signal is pulled down. Fault is cleared after fault timer expiry. In DESAT fault situation on PWML rising edge (3), rising edge is generated on G_LS (after propagation delay through CMT-TIT8243/8244 board) PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 11 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Settings Management Function Position on PCB Direct/Local Mode Non-overlap time P1 Component location Settings Jumper not present: Direct mode Jumper present: Local mode Cnovd (top) tNOV_D (ns)=5.5 * CNOVD (pF) Desaturation threshold Desaturation blanking time Component name JP2 (top) Rdesat2h-A P2 Cfr section Desaturation detection Cdesath-A Top view Bottom view PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 12 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Mechanical characteristics Top view Bottom view PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 13 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Mechanical characteristics (cnt’d) Side view Front view PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 14 of 15 1200V/1700V High Temperature (125°C) Half-Bridge SiC MOSFET Gate Driver Preliminary Datasheet Contact CISSOID S.A. Headquarters and contact EMEA: CISSOID S.A. – Rue Francqui, 3 – 1435 Mont Saint Guibert - Belgium T : +32 10 48 92 10 - F: +32 10 88 98 75 Email: sales@cissoid.com Sales Representatives: Visit our website: http://www.cissoid.com Disclaimer Neither CISSOID, nor any of its directors, employees or affiliates make any representations or extend any warranties of any kind, either express or implied, including but not limited to warranties of merchantability, fitness for a particular purpose, and the absence of latent or other defects, whether or not discoverable. In no event shall CISSOID, its directors, employees and affiliates be liable for direct, indirect, special, incidental or consequential damages of any kind arising out of the use of its circuits and their documentation, even if they have been advised of the possibility of such a damage. The circuits are provided “as is”. CISSOID has no obligation to provide maintenance, support, updates, or modifications. PUBLIC Doc. PDS-181985 V1.4 WWW.CISSOID.COM 8-Jan-21 15 of 15
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