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2022-09-16 16:00:09
DRV777 is a 7 -bit integrated motor and relay drive
Features
Support the output upper pull voltage of up to 20V
–40 ° C to 125 ° C working temperature range
#8226; Support a variety of step motor, DC motor, relay and induction coil
0.4V (typical) low output volume
–5.0V logic input every one Channel 140mA current remittance
- 1A current output of all 7 channels
compatible with 1.8V, 3.3V and 5.0V microcontroller and logic interface
[[ 123] internal free wheel diode used for induction of reflection protection
Enter the drop-down resistor allows Tri-Stating input drive
Enter the RC buffer Instrument to eliminate misunderstandings in the noise environment
low input and output leakage current
; ESD protection exceeds JESD 22
-2 kV high -voltage circuit breaker, 500 volt clean development mechanism
provides 16 -pin SOIC and tssop packaging
Application
ApplicationApplication
ApplicationApplication
123]Single -pole stepping motor drive
relay and induction load drive
solenoid valve driver
#8226; Lights and LED display
Logic flat converterGeneral low -voltage side switch application
Explanation
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DRV777
The motor driver has 7 low -output impedance drives, minimizing the power consumption in the film. DRV777 supports 1.8V to 5V CMOS logic input interfaces, so that it is compatible with various microcontrollers and other logical interfaces. Drv777 has an improved input interface to minimize the input DC current from the external drive. This device also has an input RC buffer, which greatly improves its performance under noise working conditions. All channel inputs have an internal input drop -down resistor, so the input logic is allowed to be three -state. DRV777 also supports other logical input levels, such as TTL and 1.8V; please refer to the typical feature part of the relevant information. 
As shown in the function diagram, each output of the DRV777 has an internal free wheel diode, which is connected to the public cathode configuration of the COM pin.
This device provides flexibility to increase current absorption capacity through parallel combination. In typical cases, when all 7 channels are connected, DRV777 can support load currents up to 1.0A. DRV777 has 16 stitches SOIC and 16 -pin Tssop packaging. 
123] Application information
TTL and other logic input
DRV777 input interface is specified for standard 1.8V, 3V, and 5V CMOS logic interfaces. Refer to Figure 8 and Figure 9 to determine VOL with different input voltage range and corresponding typical load current levels. The application information part shows the implementation of the DRV777 driver 1.8V relay.
Enter the RC buffer
DRV777 is characterized by an input RC buffer, which helps to prevent the noise switch from in the noise environment. The external 1K to 5K the resistor is connected in series to the input to further enhance the noise tolerance of the DRV777.
High impedance input drive
DRV777 has 300K The presence of this resistor allows the input drive trio. When the high impedance driver is connected to the channel input, the DRV777 detects that the channel input is low -level input and keeps in the closed position. When the input drive is in a high impedance state, the input RC buffer helps to increase the noise tolerance.
Power consumption on the film
Use the next formula calculation of DRV777 PD:
n is the Number of channels for activity.
VOLI is an OUTI pin voltage of load current ILI.
Heat reliability
It is recommended to limit the chip knot temperature of the DRV777 IC to below 125 ° C. IC knot temperature is directly proportional to the power consumption. Use the following formula to calculate the maximum allowance of the target IC knot temperature:
TJ (max) is the highest target temperature.
TA is the working environment temperature.
θja is the effect of sealing on the heat resistance of the environment.
Improve the package thermal performance
The package θja value under the standard conditions of the high K board is listed in the scattered rated value. The θJa value depends on the PC board layout. External heat dissipation tablets and/or cooling mechanisms, such as cold fans, can help reduce θja and improve the thermal performance of the deviceEssence
Application instance
Shan'an Pei DC motor driver
Figure 3 shows the implementation of DRV777 drive polymer DC motor. When all channels are connected, the input is driven at 5V, and the driver can absorb the current of 1A. When the voltage is 0.4V, this will generate a driver of 400m . Entering the buffer circuit is a great PWM application and requires high resistance. These two characteristics make the DRV777 an ideal choice for high -power duty -driving applications.
Single -pole step motor drive
FIG. 4 shows the implementation of DRV777 that drives the motor of the motor. Unconnected input channels can be used for other functions. When an input pin keeps the road, the internal 300K drop -down resistor pulls the corresponding input pin to the GND potential. In order to improve the antidity, external short circuit is used between unconnected input and GND pins.
Multifunctional receiver driver
When configured in Figure 5, DRV777 can be used as a multi -purpose driver. The output channel can be connected together to absorb more currents. DRV777 can easily drive motors, relays and LEDs, and the power consumption is small. The COM pin must be connected to the power supply protected by the free wheel diode.
1.8V relay driver
In order to drive low voltage relay, as shown in Figure 6, connect two or more adjacent adjacent neighbors in parallel aisle. Connecting multiple channels can reduce the channel output resistance, thereby minimizing the volume of the fixed current. DRV777 can be used to drive 3V, 5V and 12V relays, with similar implementation.
Typical features
TA +25OC.
