NCT3527U-A TR

Nuvoton Adjustable Current-Limited, Power-Distribution Switch NCT3527U NCT3527U-A NCT3527U/NCT3527U-A -Table of Content1. GENERAL DESCRIPTION ......................................................................................................... 1 2. FEATURES ................................................................................................................................. 1 3. BLOCK DIAGRAM ...................................................................................................................... 2 4. PIN CONFIGURATION AND TYPICAL APPLICATION CIRCUIT.............................................. 2 5. PIN DESCRIPTION ..................................................................................................................... 3 6. FUNCTIONAL DESCRIPTION.................................................................................................... 3 7. ELECTRICAL CHARACTERISTIC ............................................................................................. 6 8. SWITCHING CHARACTERISTICS ............................................................................................ 9 9. PACKAGE DIMENSION ........................................................................................................... 13 10. ORDERING INFORMATION..................................................................................................... 14 11. TOP MARKING SPECIFICATION ............................................................................................ 14 12. DATA SHEET REVISION HISTORY ........................................................................................ 15 -I- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 1. GENERAL DESCRIPTION The NCT3527U/NCT3527U-A is a high-side adjustable current-limited switch optimized for general purpose power distribution. The device incorporates a 70-mΩ N-channel MOSFET power switch. The NCT3527U/NCT3527U-A also supports output discharge function via external resistor that provides a controlled discharge of the output voltage stored on the output capacitor. The output current is limited when the output load reaches the current-limit threshold and a guaranteed deglitching time of 3-ms ensures that the transient voltage settles down. If after this blanking time the load current is greater than the current limit, the NCT3527U enters a latch-off state and the NCT3527U-A enters an auto-retry state. In latch-off state, the switch is turned off and FLAG# is issued to the host. The switch can be turned on again by cycling the power. In auto-retry state, the switch would be turned off for 24ms then turn-on again. The NCT3527U/NCT3527U-A provides up to 2.5A load current. When continuous heavy overloads or short-circuit causes the junction temperature to rise, an over-temperature protection mechanism (OTP) will be activated to shut the switch off to prevent catastrophic failure. Recovery from the OTP is automatic when the junction temperature returns in a reasonable range. The under-voltage lockout (UVLO) can ensure the switch is in off state unless there is a valid input voltage. The NCT3527U/NCT3527U-A is in a TSOT23-6 package. 2. FEATURES             70-mΩ High–Side MOSFET Switch Maximum 2.5A Load Current Adjustable Current Limit Trip Threshold Reverse Current Flow Blocking (no body diode) Adjustable Output Discharge Function Reverse Voltage Protection FLAG# Function Built in Soft Start Thermal Protection VIN Under Voltage Lockout Fast Current Limit Response Time Provides TSOT23-6 Green Package (Pb-free ROHS Compliance and Halogen Free) APPLICATIONS    High-Side Power Protection Switch Notebook, PC Computers Hot Plug-in Power Supplies -1- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 3. BLOCK DIAGRAM Reverse Voltage Comparator Current Sense VOUT CS VIN Deglitch (0.7-ms) ILIM Current Limit UVLO Driver Stage Deglitch (3-ms) DSG Shutdown Logic Charge Pump EN/FLAG# Thermal Protection Fault Logic GND 4. PIN CONFIGURATION AND TYPICAL APPLICATION CIRCUIT Power supply 3V ~ 5.5V VOUT 6 1 VIN VIN VOUT CIN GND 2 EN/FLAG# 3 NCT3527U NCT3527U-A (TSOT23-6) TOP VIEW 5 ILIM 4 DSG Load COUT RPU RDSG Enable Input or FLAG# Output EN / DSG FLAG# ILIM GND RILIM CIN=1uF~100uF COUT=1uF~10uF Figure 1 Typical Application Circuit -2- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 5. PIN DESCRIPTION PIN NAME I/O DESCRIPTION 1 VOUT O 2 GND Ground 3 EN/FLAG# I/O 4 DSG I External resistor used to set output discharge current. 5 ILIM O External resistor used to set current limit threshold. This pin cannot be left floating. 6 VIN Power Voltage output pin Power ground This is a bi-directional interface pin. As an input pin, pulling up this pin to enable chip and pulling down to disable chip. As an output pin, this pin goes low during fault event(s) occurs. Supply voltage input pin. 6. FUNCTIONAL DESCRIPTION Power Switch The internal power switch is a high-side N-channel MOSFET with low on-state resistance. The device incorporates an internal charge pump and gate driver circuitry to drive the N-channel MOSFET. The charge pump supplies power to the driver circuit and provides necessary voltage to pull the gate of the MOSFET above the source. The charge pump operates from input voltages as low as 3V and requires little supply current. The driver controls the gate voltage to limit the power switch. The driver incorporates circuitry that controls the rise and fall times of the output voltage to limit large current and voltage surges and provides built-in soft start functionality. EN/FLAG# This pin serves as both an input and an output. As an output, a logic level fault flag issues to host. As an input, if kept inactive (low) by the host, shuts down the power switch. An external pull up resistor is required. The FLAG# signal indicates when any of the following conditions occur:  Over-current fault persists beyond the 3-ms deglitch timeout.  The chip temperature exceeds the thermal shut down temperature limit of 150°C.  VIN is below UVLO threshold. The device features deglitch timeout to blank FLAG# assertion when an over-current condition occurs. Once the deglitching time has elapsed, this output remains asserted (active low) until cycling the VIN below the UVLO to reset the switch. Blanking allows momentary over-current to be ignored, for example, current surges caused by hot-plugging into a capacitive load or when the device is powering up, thus prevent fault alarm from being relayed to the host system. The internal over-current deglitch eliminates the need for external components to remove unwanted -3- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A pulses. This FLAG# is not deglitched when the switch is turned off due to an over-temperature shutdown or UVLO condition. Under-voltage Lockout (UVLO) An under-voltage lockout prevents the power switch from turning on until input voltage exceeds approximately 2V. If the input voltage drops below approximately 2V, UVLO turns off the power switch. Current Limit and Short Circuit Protection The current limit circuitry prevents damage to the power switch and the hub downstream port but can deliver load current through power switch up to the current limit threshold. When a heavy load or short circuit is applied to an enabled switch, a large transient current any flow until the current limit circuitry responses. Once this current is exceeded the over current threshold, the deglitching timer is counting. The timer resets if the over current condition removes before the deglitching time (3-ms, typically) has elapsed. In latch-off mode (NCT3527U), the switch is turned off if the over current condition continues up to the end of the deglitching time. By cycling the VIN below the UVLO could reset the switch. In auto-retry mode (NCT3527U-A), the switch is turned off for 24-ms if the over current condition continues up to the end of the deglitching time. Then the switch would be turned on again. The auto-retry function saves system power in case of an overcurrent or short circuit condition. Current Limit Threshold Setting The over current threshold is setting via external resistor. The NCT3527U/ NCT3527U-A uses an Short-circuit Current vs. RILIM Values internal regulation loop to provide a regulated RILIM (Ω) Min. (mA) Typ. (mA) Max. (mA) voltage on the ILIM pin. The current limit threshold 7.68k 2430 2700 2970 8.25k 2250 2500 2750 9.53k 1980 2200 2420 10.5k 1800 2000 2200 is proportional to the current sourced out of ILIM pin. Many applications requires that the minimum current limit is above a certain current level or that 11.5k 1620 1800 1980 the maximum current is below a certain current 14.3k 1350 1500 1650 level so it is important to consider the tolerance of 17.4k 1080 1200 1320 the over current threshold when selecting a value 21k 900 1000 1100 for RILIM. The traces routing the RILIM resistor to the 34.8k 500 600 700 NCT3527U/ NCT3527U-A should be as short as possible to reduce parasitic effects on the current limit accuracy. Reverse Voltage Protection The reverse-voltage protection turns off the N-channel MOSFET whenever the output voltage exceeds the input voltage 55 mV (typical) for 0.7-ms. It prevents damage to devices on the input side by preventing significant current from sinking into the input capacitance. The N-channel MOSFET is allowed to turn-on once the output voltage goes below the input voltage for the -4- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A same 0.7-ms deglitch time. The comparator will active to disable N-channel power MOSFET when OUT minuses VIN is over 55 mV for delay 0.7-ms. Discharge Function When the device is disabled, EN is de-asserted or during power up when VIN is below UVLO threshold, the discharge function is active. By connecting a resistor between DSG pin and VOUT pin, the discharge function offers a discharge path for the external storage capacitor. This is suitable only to discharge filter capacitors for limited time and cannot dissipate steady state current greater than 150mA. Thermal Shut Down The device implements a Thermal Sense to monitor the chip temperature. When the chip temperature exceeds 150C for any reasons, the Thermal Shutdown function turns off the power switch. A Hysteresis of 50C prevents the switch turning back on until the temperature drops below 100C. Input and Output Capacitor Place a 1~100uF bypass capacitor between VIN to GND, close to the device, is recommended to reduce power-supply transients that may cause ringing on the input. Furthermore, without the bypass capacitor, an output short may cause the input ringing (due to the inductance from power supply to VIN) to destroy the internal control circuitry. Additionally, bypassing the output with a 1~10uF capacitor improves the immunity of the device to short-circuit transients. Placing a high value capacitor on the output pin is recommended when large currents are expected on the output. Layout Consideration It is important to keep all traces as short as possible to reduce the effect of undesirable parasitic inductance and the switch response time to output short circuit condition. Place input and output capacitors as close as possible to the device. -5- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 7. ELECTRICAL CHARACTERISTIC ABSOLUTE MAXIMUM RATINGS ITEM RATING UNIT Input voltage, VIN -0.3 ~ 6 V Output voltage, VOUT -0.3 ~ 6 V Internally Limited A Continuous output current Peak Discharge Current, DSG 200 mA Junction temperature -40 ~ 150 C Storage temperature -50 ~ 150 C Soldering temperature Refer to IPC/JEDEC J-STD-020 Specification Electrostatic discharge protection Human Body Mode Machine Mode Electrostatic discharge protection, Latch-Up 2 kV 200 V ±100 mA NOTE： Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device .These are stress ratings only And functional operation of the device at these or any other conditions beyond those indicated under “recommended operating condition” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. THERMAL INFORMATION PARAMETER RATING UNIT TSOT23-6 0.5 W TSOT23-6, θJA 220 C/W TSOT23-6, θJC 90 C/W VALUE UNIT 3.0 ~ 5.5 V -0.3 ~ VIN+0.3 V EN/FLAG# pull up resistance 1 ~ 10 kΩ DSG discharge current 0 ~ 150 mA Continuous output current 0 ~ 2.5 A Current limit threshold resistor range for ILIM to GND 25 ~ 100 kΩ VIN capacitance 1 ~ 100 uF VOUT capacitance 1 ~ 10 uF -40 ~ 85 °C Power dissipation, PD @ TA=25C Package thermal resistance RECOMMENDED OPERATING CONDITIONS PARAMETER Input voltage, VIN Voltage on EN/FLAG# and DSG TA, Operating temperature -6- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A DC ELECTRICAL CHARACTERISTICS VIN=5V, TA=-40C to 85C, Typical Values are at TA=25C. Unless otherwise specified. PARAMETER TEST CONDITIONS MIN TYP MAX UNIT Power Switch RDS(on) Static drain-source on-state resistance IOUT = 1A, TA=25C 70 110 mΩ RDIS Output Discharge Resistance IDIS = 1mA, EN=0V, TA=25C 15 30 Ω Current Limit IOS IOS  21000 RILIM RILIM = 34.8 kΩ, TA=25C 0.5 0.6 0.7 A R ILIM = 21 kΩ, T A =25C 0.9 1.0 1.1 A RILIM = 10.5 kΩ, TA=25C 1.82 2.0 2.22 A RILIM = 7.68 kΩ, TA=25C 2.43 2.7 2.97 A RILIM = 34.8 kΩ 0.57 0.69 0.81 A RILIM = 21 kΩ 1.04 1.15 1.27 A RILIM = 10.5 kΩ 2.07 2.3 2.53 A RILIM = 7.68 kΩ 2.79 3.1 3.42 A RILIM = 34.8 kΩ 0.55 0.65 0.75 A RILIM = 21 kΩ 0.99 1.1 1.21 A RILIM = 10.5 kΩ 1.98 2.2 2.42 A RILIM = 7.68 kΩ 2.67 2.97 3.27 A VIN=5V, Current Ramp (0.001 A/us) on VOUT IOC Over-current Trip Threshold VIN=5V, Continuous Current on VOUT tIOS Response time to short circuit VIN=5V, TA=25C tIOC Over current blanking time VIN=5V, TA=25C tOCRT Retry time 5 us 2 3 4 ms 10 24 35 ms Operating Current ICC Supply current EN=5V, No Load, not including IRLIM 150 200 uA ISD Shutdown current EN=0V 45 65 uA IOUT_LEAK VOUT leakage current EN=0V 1 uA IREV Reverse leakage current to VIN VOUT=5V, VIN=0V 1 uA VIH Input logic High level TA=-40C ~ 85C VIL Input logic Low level TA=-40C ~ 85C EN/FLAG# 1.2 V 0.8 Hysteresis 0.2 IEN_LEAK Leakage current EN=5.5V or GND ISINK Sink current EN=0.4V V V 1 2 uA mA Under-Voltage Lockout UVLO Low level input voltage VIN Rising Hysteresis TA=25C 2 2.6 200 V mV Reverse Voltage Protection -7- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A VOUT-VIN Reverse voltage protection threshold 30 55 80 mV Reverse voltage blanking time 0.5 0.7 1 ms 2 3 ms Timing tr Rise time CL=10uF , RL= 5Ω, TA=25C tf Fall time CL=10uF , RL= 5Ω, RDSG= 33Ω, TA=25C 0.2 1 ms ton Turn on time CL=10uF , RL= 5Ω, TA=25C 2.5 3.5 ms toff Turn off time CL=10uF , RL= 5Ω, RDSG= 33Ω, TA=25C 0.4 1.2 ms Thermal shutdown TSD Thermal shutdown threshold Design guarantee 125 Hysteresis  150 C 50 C PARAMETER MEASURE INFORMATION VOUT RL CL Test Circuit  TIMING DIAGRAM 50% tr 50% VEN tf Ton 90% 90% VOUT VOUT 10% Toff 90% 10% 10% Turn-on Time and Turn-off Time Output Rise and Fall time VOU T Decreasing load resistance IOS IOU T IOS IOC tIOS Response time to shirt circuit waveform IOUT VOUT vs. Current limit threshold -8- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 8. SWITCHING CHARACTERISTICS -9- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 5V 5V 3.3V 3.3V 5V 3.3V 5V 5V 3.3V 3.3V -10- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 5V 5V 3.3V 3.3V RILIM=10kΩ, RLOAD=5Ω RILIM=10kΩ, RLOAD=5Ω Disable with 5Ω Load Enable with 5Ω Load RILIM=10kΩ RLOAD=1Ω RILIM=10kΩ VOUT short to ground Enable with OCP condition Enable with short circuit condition -11- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A RILIM=10kΩ, RL=1Ω RILIM=10kΩ, RL=1Ω Over current protection: Auto-retry Mode Over current protection: Latch off Mode RILIM=10kΩ CIN=560uF, No COUT Short circuit response -12- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 9. PACKAGE DIMENSION  Taping Specification -13- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 10. ORDERING INFORMATION PART NUMBER CURRENT LIMIT SUPPLIED AS PACKAGE TYPE NCT3527U Latch-off T Shape: 3,000 units/T&R 6 PIN TSOT23 (Green package) NCT3527U-A Auto-retry T Shape: 3,000 units/T&R 6 PIN TSOT23 (Green package) OPERATING TEMPERATURE RANGE Commercial, -40℃ to 85℃ Commercial, -40℃ to 85℃ 11. TOP MARKING SPECIFICATION 27XYM st 1 Line: 27 (NCT3527U/NCT3527U-A)  X: A for NCT3527U, B for NCT3527U-A  YM: The last character of calendar year (Y) + month (M) (1: Jan., 2: Feb., 3: Mar., 4: Apr., 5: May, 6: Jul., 7:Jul., 8: Aug., 9: Sep., A: Oct., B: Nov., C: Dec.) -14- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A 12. DATA SHEET REVISION HISTORY VERSION DATE PAGE DESCRIPTION A0 Jul.,2014 All First Release -15- Publication Date: Jul., 2014 Revision A0 NCT3527U/NCT3527U-A Important Notice Nuvoton Products are neither intended nor warranted for usage in systems or equipment, any malfunction or failure of which may cause loss of human life, bodily injury or severe property damage. Such applications are deemed, “Insecure Usage”. Insecure usage includes, but is not limited to: equipment for surgical implementation, atomic energy control instruments, airplane or spaceship instruments, the control or operation of dynamic, brake or safety systems designed for vehicular use, traffic signal instruments, all types of safety devices, and other applications intended to support or sustain life. All Insecure Usage shall be made at customer’s risk, and in the event that third parties lay claims to Nuvoton as a result of customer’s Insecure Usage, customer shall indemnify the damages and liabilities thus incurred by Nuvoton. -16- Publication Date: Jul., 2014 Revision A0