WS4667E
4.5A, 22mΩ, Ultra-low Ron Load Switch
with Quick Output Discharge
Descriptions
The WS4667E is a small, ultra-low Ron, single channel load switch with a controlled turn-on. The device contains an N-channel MOSFET that can operate over an input voltage range of 0.8V to 3.5V and supports a maximum continuous current of 4.5A.
This device is suitable for driving processor power rails with very strict voltage dropout tolerances. Quick rise time of the device allows for power rails to come up quickly when the device is enabled, thereby reducing response time for power distribution. The ON terminal can be directly connected with the low-voltage control signals generated by microcontrollers or low-voltage discrete logic circuits.
Pin configuration (Top view)
The WS4667E is available in the SOT23-6L package. The standard product is Pb-free and Halogen-free.
Features
- Input Voltage Range: 0.8V to 3.5V
- Ultra-Low On Resistance (RON) RON = 22mΩ at VBIAS = 5V
- 4.5 A Maximum Continuous Switch Current
- Low Control Input Threshold Enables Use of 1.2V, 1.8V, 2.5V and 3.3V Logic
- Quick Output Discharge (QOD)
- SOT23-6L Package
- ESD Performance Tested per JESD 22 2kV HBM and 1kV CDM
For detailed order information, please see page 2.
Applications
- Ultrabook™
- Notebooks/Netbooks
- Tablet PC
- Consumer Electronics
- Set-top Boxes/Residential Gateways
- Telecom Systems
Order Information
| Ordering No. | Continuous Current | Rise Time | Enable | Output Discharge Resistor | Package | Operating Temperature | Marking | Shipping |
| WS4667EAA- 6/TR | 4.5A | 3.4us | Active High | Yes | SOT23-6L | -40-85°C | 4667 EEYW | 3000/Reel& Tape |
Marking Information
4667 = Device code
EE = Special code
Y = Year code
W = Week code
Marking
Typical Application
Pin Description
| Pin Number | Symbol | I/O | Description |
| 1 | GND | — | Ground. |
| 2 | VIN | I | Switch input. Place ceramic bypass capacitor(s) between this terminal and GND. |
| 3 | NC | — | Not connected. |
| 4 | VOUT | 0 | Switch output. Place ceramic bypass capacitor(s) between this terminal and GND. |
| 5 | VBIAS | — | Bias voltage. Power supply to the device. |
| 6 | ON | I | Active high switch control input. Do not leave floating. |
Block Diagram
Absolute Maximum Ratings
| Symbol | Parameter | Value | Unit | |
| VIN | Input voltage range | -0.3∼5.5 | V | |
| VouT | Output voltage range | -0.3∼5.5 | V | |
| VBIAS | Bias voltage range | -0.3∼5.5 | V | |
| VON | Input voltage range | -0.3∼5.5 | V | |
| ImAx | Maximum continuous switch current | 5. | A | |
| T jmAx | Maximum junction temperature | 150 | °C | |
| TSTG | Storage temperature range | -60∼150 | °C | |
| TLEAD | Maximum lead temperature (10-s soldering time) | 260 | °C | |
| ESD | Electrostatic discharge protection | Human-Body Model (HBM) | ±2000 | V |
| Charged-Device Model (CDM) | ±1000 | |||
Thermal Information
| Thermal Resistance | WS4667E SOT23-6L | Unit |
| Thermal Resistance, RθJA（Junction-to-Ambient）Without Copper Pour | 198 | °C/W |
| Thermal Resistance, RθJA（Junction-to-Ambient）With Copper Pour* | 133 | °C/W |
*: Surface mounted on FR-4 Board using 2 oz, 1 square inch Cu area, PCB board size 1.5*1.5 square inches.
Recommended Operating Conditions
| Symbol | Parameter | Value | Unit |
| VIN | Input voltage range | 0.8～VBIAS–2 | V |
| VBIAS | Bias voltage range | 3～5.5 | V |
| VON | ON voltage range | 0～5.5 | V |
| VOUT | Output voltage range | 0～VIN | V |
| TJ | Junction temperature range | -40～125 | °C |
| TA | Ambient temperature range | 0～85 | °C |
| CIN | Input capacitor | 1 | μF |
| CL | Output capacitor | 0.1 | μF |
Electrical Characteristics
VBIAS=5.0V, Cin=1uF, TA=25°C, unless otherwise noted.
| Parameter | Symbol | Test Conditions | Min | Typ | Max | Unit | |
| VBIAS Quiescent Current | 10.VBIAS | IOUT =0mA, VIN = 3.OV | 20 | 40 | pA | ||
| VBIAS Shutdown Current | ISD.VBIAS | VON = OV , VOUT = OV | 0.1 | 1 | pA | ||
| VIN Shutdown Current | ISD.VIN | VON = OV , VOUT = OV | VIN = 3.OV | 0.001 | 0.3 | pA | |
| VIN = 2.5V | 0.001 | 0.3 | |||||
| VIN = 2.0V | 0.001 | 0.3 | |||||
| VIN = 1.05V | 0.001 | 0.3 | |||||
| VIN = 0.8V | 0.001 | 0.3 | |||||
| ON Pin Input Leakage Current | ION | VON = 5.5V | 0.1 | 1 | pA | ||
| ON Logic High Input Voltage | VON.H | VBIAS = 3.OV to 5.5V | 1. | V | |||
| ON Logic Low Input Voltage | VON.L | VBIAS = 3.OV to 5.5V | 0.4 | V | |||
| ON-state Resistance | RoN | louT = -1.0A | VIN = 3.OV | 22 | 40 | ma | |
| VIN = 2.5V | 22 | 40 | |||||
| VIN = 2.0V | 22 | 40 | |||||
| VIN = 1.05V | 22 | 40 | |||||
| VIN = 0.8V | 22 | 40 | |||||
| Output Pull-down Resistance | Rao | VIN = VOUT=5.0V, VON = OV | 260 | Ω | |||
Electrical Characteristics (Continued)
VBIAS=3.0V, Cin=1uF, TA=25°C, unless otherwise noted.
| Parameter | Symbol | Test Conditions | Min | Typ | Max | Unit | |
| VBIAS Quiescent Current | lo.vms | louT =0mA,VIN = 1.0V | 12 | 25 | μA | ||
| VBIAS Shutdown Current | ISD.VBIAS | VON = OV , VOUT = OV | 0.1 | 1 | μA | ||
| VIN Shutdown Current | Iso.viN | VON = OV , VOUT = OV | VIN = 1.05V | 0.001 | 0.3 | μA | |
| VIN = 0.8V | 0.001 | 0.3 | |||||
| ON Pin Input Leakage Current | ION | VON = 5.5V | 0.1 | 1 | μA | ||
| ON Logic High Input Voltage | VON.H | VIN = 0.8V to 1.0V | 1. | V | |||
| ON Logic Low Input Voltage | VON.L | VIN = 0.8V to 1.0V | 0.4 | V | |||
| ON-state resistance | RON | IOUT = -1.0A | MN = 1.0V | 22 | 40 | mΩ | |
| VIN = 0.8V | 22 | 40 | |||||
| Output pull-down resistance | RPD | VIN = VOUT=1.0V, VON = OV | 260 | Ω | |||
Switching Characteristics Measurement Information
Switching Characteristics
| Parameter | Test Conditions | Min Typ Max | Unit |
| VIN = 2.5V, VON = VBIAS = 5V, TA = 25 °C (unless otherwise noted) | |||
| tON Turn-on time | RL= 10Ω, CL= 0.1uF | 4.1 | μs |
| toFF Turn-off time | 1.2 | ||
| tR VOUT rise time | 3.4 | ||
| 2 | |||
| tF VOUT fall time | |||
| to ON delay time | 3.1 | ||
| VIN = 1.05V, VON = VBIAS = 5V, TA = 25 °C (unless otherwise noted) | |||
| toN Turn-on time | RL= 10Ω, CL= 0.1uF | 4 | μs |
| toFF Turn-off time | 1.3 | ||
| tR VOUT rise time | 1.5 | ||
| tF Vou-r fall time | 1.8 | ||
| to ON delay time | 3.4 | ||
| VIN = 1.05V, VON = 5V, VBIAS = 3.3V, TA = 25 °C (unless otherwise noted) | |||
| tON Turn-on time | RL= 10Ω, CL.= 0.1uF | 7 | μs |
| toFF Turn-off time | 2 | ||
| tR VOUT rise time | 5 | ||
| 2 | |||
| tF Vou-r fall time | |||
| to ON delay time | 5.5 | ||
Typical Characteristics
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Working Waveforms
Detailed Description
Overview
The WS4667E device is a 3.5V, 4.5A load switch in a DFN3x2-8L package. To reduce voltage drop for low voltage and high current rails, the device implements an ultra-low resistance N-channel MOSFET. The device has a controlled, fixed slew rate for applications that require a specific rise-time. During the shutdown, the device has very low leakage currents, thereby reducing unnecessary leakages for downstream modules during standby. The integrated control logic, driver, and output discharge FET eliminate the need for ny external components, which reduces solution size and bill of materials (BOM) count.
ON and OFF Control
The ON pin controls the state of the load switch. ON is active high and has a 1.2 V ON pin enable threshold, making it capable of interfacing with low-voltage signals. The ON pin is compatible with standard GPIO logic thresholds. It can be used with any microcontroller with 1.2 V or higher GPIO voltage. This pin cannot be left floating and must be driven either high or low for proper functionality.
Input Capacitor (CIN) (Optional)
To limit the voltage drop on the input supply caused by transient inrush currents when the switch turns on into a discharged load capacitor or short-circuit, a capacitor needs to be placed between VIN and GND. A 1µF ceramic capacitor, CIN, placed close to the pins, is usually sufficient. Higher values of CIN can be used to further reduce the voltage drop in high-current applications. When switching heavy loads, it is recommended to have an input capacitor about 10 times higher than the output capacitor (CL) to avoid excessive voltage drop.
Output Capacitor (CL) (Optional)
Because of the integrated body diode in the NMOS switch, a CIN greater than CL is highly recommended. A CL greater than CIN can cause VOUT to exceed VIN when the system supply is removed. This could result in current flow through the body diode from VOUT to VIN. A CIN to CL ratio of 10 to 1 is recommended for minimizing VIN dip caused by inrush currents during startup; however, a 10 to 1 ratio for capacitance is not required for the proper functionality of the device. A ratio smaller than 10 to 1 (such as 1) could cause slightly more VIN dip upon turn-on because of inrush currents.
Quick-Output Discharge
When the switch is disabled， an internal discharge resistance is connected between VOUT and GND to remove the remaining charge from the output. This resistance has a typical value of 260 Ω and prevents the output from floating while the switch is disabled. For best results, it is recommended that the device gets disabled before VBIAS falls below the minimum recommended voltage.
Layout guide
For best performance, all traces should be as short as possible. To be most effective, the input and output capacitors should be placed close to the device to minimize the effect that parasitic trace inductance may have on normal and short-circuit operation. Using wide traces for VIN, VOUT, GND helps minimize parasitic electrical effects along with minimizing the case-to-ambient thermal impedance.
PACKAGE OUTLINE DIMENSIONS
| Symbol | Dimensions in Millimeters | |||
| Min. | Typ. | Max. | ||
| A | 1.05 | – | 1.25 | |
| Al | 0 | – | 0.15 | |
| A2 | 1.00 | 1.10 | 1.20 | |
| b | 0.30 | 0.40 | 0.50 | |
| c | 0.10 | – | 0.21 | |
| D | 2.72 | 2.92 | 3.12 | |
| E | 2.60 | 2.80 | 3.00 | |
| El | 1.40 | 1.60 | 1.80 | |
| e | 0.95BSC | |||
| el | 1.80 | 1.90 | 2.00 | |
| L | 0.30 | – | 0.60 | |
| Ll | 0.59Ref | |||
| L2 | 0.25Ref | |||
| 0 | 0 | – | 8 | |
TAPE AND REEL INFORMATION
| RD | Reel Dimension |  |
| W | Overall width of the carrier tape | |
| P1 | Pitch between successive cavity centers | |
| Pin1 | Pin1 Quadrant |
OmniVision reserves the right to make changes to its products or to discontinue any product or service without further notice. OmniVision and the OmniVision logo are trademarks or registered trademarks of OmniVision Technologies, Inc. All other trademarks are the property of their respective owners.
4275 Burton Drive
Santa Clara, CA 95054
USA
Tel: + 1 408 567 3000
Fax: + 1 408 567 3001
www.ovt.com
2022/1/4 – Rev. 0.5
Documents / Resources
 | OMNI-VISION WS4667E Ultra-low Ron Load Switch [pdf] User Manual WS4667E Ultra-low Ron Load Switch, Ultra-low Ron Load Switch, Ron Load Switch, Load Switch, SOT23-6L |
