LTC1710 SMBUS...

  • 2022-09-15 14:32:14

LTC1710 SMBUS dual single -chip high -pressure side switch

Features

Two 0.4 /300MA N channel switch

There are MS8 and SO-8 packaging

SMBUS and I2C compatible [123 ]

VIL 1.V and VIL 6V

14 μ independent drain connection: Low current

Three addresses from a three -state address pin

At most Independent control of six switches

built -in power -power resolution timer

Built -in underwriting lock

Palm computer power management

] Computer peripheral control

Laptural computer power board switch

Portable equipment power control

Industrial control system

ACPI SMBUS interface

Description

LTC #174; 1710 SMBUS dual switch has two built -in 0.4 //300MA switch interface controlled by SMBU. The input voltage range of the LTC1710 in 14 μA (3.3V) is 2.7V to 5.5V, while maintaining the 0.6V VIL and 1.4V VIH input threshold specified by SMBUS. Use 2 -line interfaces, CLK and Data, LTC1710 independently follow the SMBUS send byte protocol to control two 0.4 internal N channel power switches, which fully enhances the vehicle charging pump. LTC1710 has a three -state programming that allows a total of three addresses with addresses of a total of three different addresses. There are six available switches on the same line. LTC1710 also has an independent user control drainage supply (SW0D) switching 0 to control SMBUS peripheral devices that can be used to control the use of different power supply.

Absolute maximum rated value

(Reference voltage of GND pins) (Note 1)

Input power supply voltage (VCC) - 0.3 Volume to 6 volts

The input power supply voltage (VCC)

as a low -voltage side switch -0.3 volt to 3.6 volts

data, CLK (bus pin pin pin 6, 5) – 0.3 to 6 volts*

AD1 (address pins 3) – 0.3V to VCC+0.3V

OUT0, OUT1 (output pin 2,7) - 0.3 volt to 6 volts

SW0D (switch 0 discharge 1) — 0.3 volts to 6 volts

Output 0, output 1 (output pin 2, 7)

Consecated 300 mAh

pulse, lt; 10μs (non -repeated) 1A number

The working temperature range

LTC1710C 0 ° C to 70 ° C

LTC1710i -40 ° C to 85 ° C

Celsius 125

] Storage temperature range –65 ° C to 150 ° C

Lead temperature (welding, 10 seconds) 300 degrees Celsius

Electric characteristics ta u003d 25 ° C, VCC u003d SW0D u003d 5V, unless otherwise separate another There are explanations.

Electric characteristics TA u003d 25 ° C, VCC u003d SW0D u003d 5V, unless there is another instructions.

indicates the standard temperature range suitable for the entire operation.

Note 1: The absolute maximum rated value means that the value device that exceeds life may be damaged.

Note 2: Provide about 3%lagging to ensure stable operation and eliminate error triggers caused by small VCC faults.

Note 3: Measure the data input from VCC GT; VUVLO to SMBU.

Note 4: The frequency of the oscillator is not directly tested, but according to the boot time.

Note 5: SMBUS timing specifications are guaranteed, but not tested.

Note 6: Establish ON from SMBUS to stop conditions.

Note 7: Enable OFF when receiving stop conditions from SMBUS.

Typical performance features

pin function

SW0D (pin 1): The drain power supply of switch 0. User programs can from 0V to VCC.

OUT0 (pin 2): Source output of switch 0. The maximum load is 300 mAh; controlled by the command byte by the command byte.

AD1 (pin 3): three -state programming address pins. It must be directly connected to VCC, GND or VCC/2 (two resistors ≤1m). Don't let this sell.

GND (pin 4): ground connection.

CLK (pin 5): serial clock interface. Be sure to pull it to the VCC with an external resistor. The pull -up current must be limited to 350 μA.

Data (pin 6): Open the drain connection serial data interface. The external resistor must be pulled to VCC. This upper pull current must be limited to 350 μA.

OUT1 (pin 7): Source output of switch 1. The maximum load is 300 mAh; the second LSB control of the command byte.

VCC (pin 8): Enter the power supply voltage. The scope of work ranges from 2.7 to 5.5 volts.

Operation

SMBUS operation

SMBUS is a serial bus interface, data and clock with only two bus line lines, data and clocks, clocks, clocks, and clocks, and clocks, clocks, clocks, and clocks, and clocks, clocks, clocks, and clocks. Used to control low -power peripheral equipment portable equipment. It consists of a master, also known as the host and the device. SMBUS's master is always the state that starts with the device that communicates with the passage through the machine by changing the data and the CLK line. The SMBUS specification establishes a set of equipment on the bus bus that must be communicated. The protocol used by the LTC1710 is Send Byte Pro Tocol. In this protocol, the host first issued a high high -level switching data cable from high level to low level CLK. (Because there may be more than one owner on the same bus, if two hosts try to control the data cable at the same time; the first host outputs one, and the other output owner is a zero arbitration. It will start the bus to wake up and prepare to shift in the next data byte.

Operation

Then the host sends the first byte. Communication. The last one means whether it is reading or writing logic (zero logic). Because the LTC1710 is a master who can only be written by a master, it will ignore it. If it wants to from the LTC1710, even the address sent by the host The matching LTC1710. After receiving the first byte, the device (LTC1710) with the matching address (LTC1710) confirms that the host is confirmed before the next rising clock edge. So far, all other unsatisfactory subordinate devices are all all subordinate devices. Will no longer exist to the original state of standby and wait for the next starting signal. At the same time, after receiving the confirmation, the main server will send the command by the main server (see Table 1). ]

After receiving the command byte, the data cable is required from the device (LTC1710) to lower the data cable by the next clock cycle. This host then sends a stop signal, which is the data cable when the CLK line is high. Effective data has been shifted into the output locks of the last confirmation signal, but it will not open the detection signal until the output switch is stopped until the stop. The device is executed on the stop signal, although the valid data is loaded in their output locks at different times. For example, the security is shown in Figure 1. ) It will be considered a mistake, andAnd reject all previous data. The address of the address LTC1710 is 10110xx; 5 MSB is hard -connected, but the two LSBs can be used by the user with the help of the three -state address pins. Refer to the configuration of Table 2 pin and its corresponding address.

In order to save spare current, it is best to pin the address to VCC or GND. If the three LTC1710 is needed, then the address PIN can be bound to the third state by using two equivalent resistors (≤1m) to measure the VCC/2, as shown in Figure 2.

Charging pump

In order to fully enhance the internal N -channel power switch, the internal charge pump is used to increase the maximum 6V above the gate driver VCC. The maximum reasons for the output voltage of the charge pump is to protect the internal driving switch from the excessive door. When the output voltage of the charge pump is 6V, the feedback network is used to limit its output higher than VCC. To prevent the power switch from opening too fast, the internal current source is switched to the output and power door switching of the charge pump to control the slope rate. Because the charge pump only drives the internal switch, only a small amount of current must be repaired. Therefore, all charge pumping electric containers are integrated. The drainage pipe of the switch 1 is connected to the VCC internally, but the drainage of the switch 0 is controlled by the user through No. 1 pin. In other words, the SMBUS device uses different power supply voltages, which can be switched by the same LTC1710 at the same time.

Powering and low -voltage locks

LTC1710 starts with the low of the two gate drivers. An internal power -powered reset (POR) signal is prohibited until the VCC locks the threshold (usually 2V) after VCC is under pressure. The circuit includes some lag and delay to avoid interference reset. Once the operation starts, VCC must be at least 100 μs lower than the threshold to trigger another POR sequence.

Input threshold

The estimated power supply voltage is expected to be lower and lower, SMBU's VIH is 1.4V and VIL is 0.6V. Some SMBUS parts may violate this strict SMBUS by specifying a higher VIH value for the corresponding higher input power supply voltage. The LTC1710 meets and maintains a constant SMBUS input threshold specification within the entire power supply range of 2.7V to 5.5 volts.

Hot turnover

In an unlikely situation, the power switch is over the hot shutdown circuit, which is close to two switches, which will activate and turn off the gate to drive two switches. The threshold of the heat shutdown circuit is 120 ° C and lags 15 ° C.

Typical application LT1710, use 1521-3.3 with LT #174; CAN to switch the 3.3V/300mA power supply to A to the load (Figure 3). In addition, in LT1304-5,With a help, the LT1710 can be used to make the voltage booster regulator used to disconnect and keep the low backup current of 22 μA (Figure 5).