YB1901 2.0A High-Side Power Switch with Flag Description Features The YB1901 is a low operation voltage, single N-channel MOSFET high-side power switch, optimized for low power consumption system. A small internal charge-pump circuitry is built in the YB1901 to drive the internal MOSFET switch for reaching an average RDS(ON) resistance of 120mΩ. A fault flag output is available to indicate an abnormal condition during operation. Some other features include low in-rush current during plug-in, thermal shutdown to prevent switch failure from high-current loads, under-voltage lock-out to keep the chip off when below normal operation supply, a short-circuit protection to avoid grounded big current. The quiescent current needed to run the change-pump is as low as 60μA at 5V input. It makes the device ideal for portable battery operated system. Built-In N-Channel MOSFET Typical RDS(ON) Resistance : 120 mΩ Low Quiescent Current : 60μA at 5V Low Shutdown Current : <1μA Current Limit at 2.0A Wide Input Voltage Range : 2.7 ~ 5.5V Hot Plug-In Application 2.4V Under-Voltage Lock-Out Thermal Shutdown Protection Short-Circuit Protection Reverse Current Flow Blocking Open-Drain Fault Flag SOT-25, MSOP8, SOP8 Packages Green Package (RoHS) Available Applications The YB1901 power switch is available in SOT-25, MSOP8, SOP8 packages. PDA, DSC, GPS USB Peripherals PC Cards PCMCIA Cards Notebook PC Battery-Charger Circuits Battery-Powered Instruments Typical Application Circuit 2.7~5V VIN System Power Vout YB1901 ON OFF 1u 100K 1u EN OCB Fault Flag Figure 1: Typical Application Circuit YB1901 Rev.1.2 www.yobon.com.tw 1 YB1901 2.0A High-Side Power Switch with Flag Pin Configuration OCB 1 GND 2 EN 3 5 VOUT 4 VIN GND 1 8 VOUT VIN 2 7 VOUT VIN 3 6 VOUT EN 4 5 OCB SOT23-5 SOP8 or MSOP8 Figure 2: Pin Configuration Pin Description Table 1 Name EN Description Pull low to enable the chip, active high (active low is optional). GND Ground pin. OCB Open-drain fault flag. Connect a 100KΩ resistor to VIN. VIN Input supply. Bypass with a capacitor to GND. VOUT Output voltage. Bypass with a capacitor to GND. Ordering Information Table 2 Order Number Enable Package Type Supplied As YB1901ST25H Active High SOT23-5 3000 Units Tape & Reel Y90H YB1901SPX8H Active High SOP-8 2500 Units Tape & Reel 第一行 Y90H 第二行 SPX8 YB1901MXX8H Active High MSOP-8 2500 Units Tape & Reel Y90HM8 YB1901ST25L Active Low SOT23-5 3000 Units Tape & Reel Y90L YB1901SPX8L Active Low SOP-8 2500 Units Tape & Reel 第一行 Y90L 第二行 SPX8 YB1901MXX8L Active Low MSOP-8 2500 Units Tape & Reel Y90LM8 YB1901 Rev.1.2 www.yobon.com.tw Package Marking 2 YB1901 2.0A High-Side Power Switch with Flag Absolute Maximum Ratings(Note 1) Supply Voltage...............................-0.3V to 6 Output Voltage .............. -0.3V to (VIN + 0.3V) Output Short-Circuit Duration..............Infinite Junction Temperature ..........................150℃ Storage Temperature .............-65℃ to 150℃ Lead Temperature................................250℃ ESD Susceptibility (HBM) .................... 3KV ESD Susceptibility (MM) .......................300V Recommended Operating Conditions (Note 2) Input Supply Voltage ...............2.7V to 5.5V Operating Temperature ......... -40℃ to 85℃ Thermal Information (Note 3) Thermal Resistance (SOT-25, θJA) ...280℃/W Internal Power Dissipation (SOT-25, PD) .. 0.4W Note: 1. Exceeding these ratings may damage the device. 2. The device is not guaranteed to function outside of its operating conditions. 3. θJA is measured in free air at TA = 25℃ on a low effective thermal conductivity board. YB1901 Rev.1.2 www.yobon.com.tw 3 YB1901 2.0A High-Side Power Switch with Flag Electrical Characteristics Table 3 (VIN=5V, CIN= COUT=1μF, TA=25°C, unless otherwise noted.) PARAMETER Input Voltage Rage Output MOS RDS(ON) CONDITION MIN 2.7 YB1901, IOUT=0.5A TYP 5 MAX 5.5 Unit V 120 mΩ 60 uA mA us Supply Current Iout=0 Load current Output Turn-on Rising Time RL=10Ω, 90% Settling 500 Current Limit Threshold YB1901, VOUT=4V 1.6 2.2 2.8 A Short-circuit Current YB1901, Vout=0V 0.1 1.5 1.73 A 1.5 1.7 200 1.85 2.4 V mV uA uA V 200 mV 135 20 °C °C EN Input Threshold VIN=5V, Rising EN Input Hysteresis Shutdown Supply Current Output Leakage Current EN=Non-active, Vout=0V VIN Under Voltage Lockout VIN Under Voltage Hysteresis Thermal Limit Thermal Limit Hysteresis OCB assertion or OCB Deglitch deassertion OCB Output Low Voltage ISINK =1mA, VIN=5V OCB Off-State Current VOCB =VIN YB1901 Rev.1.2 www.yobon.com.tw 420 1 1 7.5 10 ms 0.4 1 V uA 4 YB1901 2.0A High-Side Power Switch with Flag Typical Characteristics At TA=25℃, VIN=5V, CIN=COUT=1.0μF, VEN=VIN, unless otherwise noted. Turn on delay time and rising time Turn off delay time and falling time RL=5Ω Cout=100uF Inrush current and different load capacitance RL=5Ω UVLO at rising Thermal shutdown reponse RL=1Ω Cout=47uF UVLO at falling RL=33Ω YB1901 Rev.1.2 RL=5Ω Cout=100uF www.yobon.com.tw RL=33Ω 5 YB1901 2.0A High-Side Power Switch with Flag Inrush current response Short circuit response at start up Cout=47uF Short circuit and Enable pin enable Cout=47uF Resistance load inrush response Cout=47uF Capacitance load inrush response RL=2Ω Cout=47uF Capacitance load inrush response Cout=47uF CL=470uF hot plug-in Cout=100uF CL=10uF hot plug-in Rdson VS Input Voltage Quiecsent current VS Input Voltage 160 70 140 120 50 Rdson (mΩ) Qeiescent Current (uA) 60 40 30 100 80 Iout=100mA 60 20 40 10 20 0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 0 2.5 Input Voltage (V) 3.0 3.5 4.0 4.5 5.0 5.5 Input Voltage (V) YB1901 Rev.1.2 www.yobon.com.tw 6 YB1901 2.0A High-Side Power Switch with Flag Function Block VIN UVLO Charge pump OSC VOUT Current Limit BIAS EN Delay OCB Thermal Protection GND Figure 3: Function Block Functional Description The YB1901 is an N-channel high-side power switch with an internal charge-pump circuitry to drive the switch. The enable signal is either active high. It is ideal for battery-powered applications and adaptor card operation with less than 2.0A requirement. NMOS Switch The drain of the NMOS is connected to VIN and the source to VOUT. The bulk contact is grounded, instead of the source terminal, so there is no parasitic diode between the two terminals. It prevents reverse current flow from VOUT to VIN if VOUT being forced to higher voltage than VIN when the enable is inactive. This feature makes the main difference between YB1901 and a traditional external MOSFET. YB1901 Rev.1.2 Chip Enable The enable signal is available with either or active low of customer’s request. When the enable is inactive, the switch is turned off, the internal oscillation stopped, the charge pump discharged, and the whole chip current consumption is kept at lower than 0.1μA typically. When the enable is set active, the oscillation starts, the charge pump works. But it takes time building up the control voltage necessary to drive the MOSFET switch. The turn-on delay time is around 0.42ms typically. Floating the enable pin may cause unpredictable operation. It should be avoided. Under-Voltage Lock-Out (UVLO) UVLO prevents the chip from turning on until a safe input voltage is reached. For YB1901 UVLO is set to around 2.4V, and there is a hysteresis voltage of 0.2V www.yobon.com.tw 7 YB1901 2.0A High-Side Power Switch with Flag between rising and falling. That UVLO shuts down the chip when input voltage drops below 2.4V and allows starting up the chip when input voltage above 2.6V. Short-Circuit Protection If the VOUT pin is connected to ground or nearly ground level by mistake, the short-circuit protection circuit will come active and put a current limit over the switch to protect the switch from over-current. The current limit is set around 1.5A. Overload Current Limit The YB1901 is designed to work below 2.0A. If the current load outgrows 2.0A, it will trigger the Overload Current Limit Circuitry. The max current limit is set at 2.0A. If the protection circuit is activated, it send out a fault signal from the OCB pin. It does not shutdown the circuit. Thermal Shutdown The thermal shutdown is deployed to protect the switch from damage if the silicon temperature rises above 135°C approximately. If the circuit is triggered, the chip will turn on again when the silicon temperature drops around 20°C below. Fault Flag There is a fault flag signal (OCB) available with YB1901 to indicate the occurrence of abnormal operation. The abnormal operation includes Short-Circuit, Thermal shutdown and Overload Current Limit. When the fault happens and lasts for more than 7.5ms typically, the flag will be asserted. OCB is designed in open-drain YB1901 Rev.1.2 structure. Connecting a resistor of 100K ohm to VIN is necessary for the pin to signal (active low) a faulty condition. Application Information The YB1901 featured very low quiescent current and very low RDS(ON) and making them ideal for battery-powered applications. The ENABLE control pin is TTL compatible and driven by 1.7V beyond making the YB1901 an ideal level-shifting load switch. Input Capacitor Selection A 1μF or larger input capacitor is recommended to prevent load transients from affecting upstream circuits. CIN should be located as close to the device VIN pin as practically. There is no specific requirement type of capacitor is recommended. However, for higher current operation, ceramic capacitors are recommended for CIN. Output Capacitor Selection For proper slew operation, a 0.1μF or greater is recommended. The output capacitor has also no specific capacitor type requirement. If desired, COUT maybe increased without limit to accommodate any load transient. Reverse Output-to-Input Voltage Conditions and Protection Under normal conditions, there is no parasitic diode between the output & input of the load switch. In case of VOUT exceeding VIN, there is no excessive current flow from VOUT to VIN. This reverse-blocking ability secures the use of such a power switch. www.yobon.com.tw 8 YB1901 2.0A High-Side Power Switch with Flag Thermal Considerations The YB1901 is designed to deliver a continuous load current. The maximum limit is package power dissipation. At any given ambient temperature, the maximum package power dissipation can be determined by the following equation: than normal traces, and GND should be connected to a ground plane. For best performance, CIN and COUT should be placed close to the package pins. PD(MAX) = [ TJ(MAX) - TA ] / θJA Constraints for the YB1901 are maximum junction temperature TJ(MAX) = 125℃, and package thermal resistance, θJA =280℃/W. The maximum continuous output current for YB1901 depends on package power dissipation and the RDS(ON) of MOSFET at TJ(MAX). Typical conditions are calculated under normal ambient condition where TA = 25℃. At 85℃, PD(MAX) = 143mW. At TA = 25℃, PD(MAX) = 357mW. The maximum current is calculated by the following equation: IOUT < (PD(MAX) / RDS(MAX))1/2 For example, if VIN = 5V, RDS(MAX) = 100mΩ and TA = 25℃, IOUT(MAX) = 1.89A. Thermal Shutdown is employed to protect the device damage when temperature is over 120℃. PCB Layout Consideration To maximize YB1901 performance, some board layout rules should be followed: VIN and VOUT should be routed using wider YB1901 Rev.1.2 www.yobon.com.tw 9 YB1901 2.0A High-Side Power Switch with Flag Package Information (SOT23-5) YB1901 Rev.1.2 www.yobon.com.tw 10 YB1901 2.0A High-Side Power Switch with Flag Package Information (MSOP-8) YB1901 Rev.1.2 www.yobon.com.tw 11 YB1901 2.0A High-Side Power Switch with Flag Package Information (SOP-8) NOTICE: y The information described herein is subject to change without notice. y Yobon does not assume any responsibility for use of any circuitry or applications described herein, nor does it convey any patent license. YB1901 Rev.1.2 www.yobon.com.tw 12