Hojas tencicas ta7257p (puenteh)

TA7257P
TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic

TA7257P
Full-Bridge Driver (H-Swithch) For DC Motor (Driver for Switching between Forward and Reverse Rotation)
The TA7257P is a Full Bridge Driver for blashed DC Motor Rotation control. Forward Rotation, Reverse Rotation, Stop and Braking operations are available. It’s designed for Loading and Reel Motor driver for VCRand Tape Deck, and any other consumer and industrial applications. TA7257P have Operation Supply Voltage terminal and Motor Driving Supply Voltage terminal independently therefore Servo control operation is applicable.

Features
Output current up to 1.5 A (AVE.), and 4.5 A (PEAK)

Weight: 1.88 g (typ.)

Four different modes (forward rotation, reverse rotation, stop, and brake) are supported.Built-in overcurrent protection and thermal shutdown circuit Operating voltage range: VCC (opr.) = 6 to 18 V, VS (opr.) = 0 to 18 V No malfunction occurs even if VCC is higher than VS or Vice versa.

Block Diagram

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Pin Function
Pin No. 1 2 3 4 5 6 7 Symbol IN1 IN2 OUT1 GND OUT2 VS VCC Input terminal Input terminal Output terminal GND terminal Output terminalSupply voltage terminal for Motor drive Supply voltage terminal for Logic Functional Description

Function
IN1 1 0 1 0 IN2 1 1 0 0 OUT1 L L H High impedance OUT2 L H L Brake CW/CCW CCW/CW Stop Mode

Maximum Ratings (Ta = 25°C)
Characteristics Supply voltage Peak Operate PEAK AVE. Symbol VCC (max) VCC (opr.) IO (PEAK) IO (AVE.) PD Topr Tstg Rating 25 18 4.5 1.5 12.5 (Note) −30 to 75 −55 to 150Unit V

Output current Power dissipation Operating temperature Storage temperature

A W °C °C

Note:

Tc = 75°C

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Electrical Characteristics (Ta = 25°C)
Characteristics Symbol ICC1 Supply current ICC2 Upper Saturation voltage Lower Upper Lower Output transistor leakage current Input voltage 1, 2 Upper Lower VS1U VS1L VS2U VS2L ILU ILL VIN (H) VIN (L) VF U VF LISC IIN ― ― VCC = 18 V, IO = 1.1 A ― Test Circuit Test Condition VCC = 18 V Output OFF stop mode VCC = 18 V Output OFF CW/CCW mode VCC = 18 V, IO = 0.1 A Min ― ― ― ― ― ― ― ― 3.0 ― ― ― ― ― ― ― Typ. 6.5 10 0.7 0.6 1.0 0.9 ― ― ― ― 2.0 1.25 3.5 1 Max 13 mA 20 1.0 0.9 1.4 1.3 100 100 ― 0.8 ― ― ― 10 µA V Unit

VS = 18

―

Tj = 25°C, pin (1) and pin (2)

V

Diode forward voltage Limiting currentInput current

― ― ―

IF = 1.0 A

V A µA

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Application Note
(1) Input circuit
Input circuit is shown in Figure 1. It’s a “Low active” type voltage comparator that’s one input connect to Input terminal (pin (1), or (2)) and the other to built−in temperature compensated voltage reference (VTH = 1.4 V Typ.) If a voltage above VIN (H) fed into the Input Terminalthat means “Logic 1” and less than VIN (L) or connect to GND means “Logic 0”.

Figure 1
(2) Basic application circuit

Figure 2
Note 1: An optimum C or R value varies depending on what type of motor is in use. Select each optimum value by experiment. Note 2: Do not use silicone rubber to mount a heat radiation panel. Note 3: Utmost care is necessary in the design of the output line, VCC (VM,VS, VEE) and GND line since IC may be destroyed due to short−circuit between outputs, to supply, or to ground. Note 4: Switching the inputs may allow a punch-through current to flow. Keep the IC device in the STOP mode (for at least 100 µs) during the switching. Alternatively, insert a current limiting resistor R. Note 5: When the power is rising or falling, the IC device may not able to functionnormally. Before employing it, make sure that this nature of the IC device raises no problem to your application. Note 6: When turning on the power for the IC device, apply VS after VCC (or VCC and VS simultaneously). When shutting off the power, drop VS before VCC (or Vs and VCC simultaneously). Note 7: The thermal shutdown or overcurrent protection circuit cannot protect the IC device in...