17531A datasheet(10/20 Pages) FREESCALE

10 / 20 page

Analog Integrated Circuit Device Data

Freescale Semiconductor

17531A

FUNCTIONAL DESCRIPTION

INTRODUCTION

FUNCTIONAL DESCRIPTION

INTRODUCTION

The 17531A is a monolithic dual H-Bridge ideal for

portable electronic applications to control bipolar step motors

and brush DC motors such as those found in camera len

assemblies, camera shutters, and optical disk drives. The

device features an on-board charge pump, as well as built-in

shoot-through current protection and undervoltage

shutdown.

The 17531A has four operating modes: Forward, Reverse,

Brake, and Tri-Stated (High Impedance). The MOSFETs

comprising the output bridge have a total source + sink

RDS(ON) ≤ 1.2 Ω.

The 17531A can simultaneously drive two brush DC

motors or one bipolar step motor. The drivers are designed to

be PWM’ed at frequencies up to 200 kHz.

FUNCTIONAL TERMINAL DESCRIPTION

LOGIC SUPPLY (VDD)

The VDD terminal carries the logic supply voltage and

current into the logic sections of the IC. VDD has an

undervoltage threshold. If the supply voltage drops below the

undervoltage threshold, the output power stage switches to a

tri-state condition. When the supply voltage returns to a level

that is above the threshold, the power stage automatically

resumes normal operation according to the established

condition of the input terminals.

LOGIC INPUT CONTROL (IN1A, IN1B, IN2A, AND

IN2B)

These logic input terminals control each H-Bridge output.

IN1A logic HIGH = OUT1A HIGH. However, if all inputs are

taken HIGH, the outputs bridges are both tri-stated (refer to

Table 6, Truth Table, page 9).

POWER SAVE (PSAVE)

The PSAVE terminal is a HIGH = TRUE power save mode

input. When PSAVE = HIGH, all H-Bridge outputs (OUT1A,

OUT1B, OUT2A, and OUT2B) are tri-stated (High-Z),

regardless of logic inputs (IN1A, IN1B, IN2A, and IN2B)

states, and the internal charge pump and low voltage

detection current are shut off to save power.

H-BRIDGE OUTPUT (OUT1A, OUT1B, OUT2A, AND

OUT2B)

These terminals provide connection to the outputs of each

of the internal H-Bridges (see Figure 2, 17531A Simplified

Internal Block Diagram, page 2).

MOTOR DRIVE POWER SUPPLY (VM1 AND VM2)

The VM terminals carry the main supply voltage and

current into the power sections of the IC. This supply then

becomes controlled and/or modulated by the IC as it delivers

the power to the loads attached between the OUTput

terminals. All VM terminals must be connected together on

the printed circuit board.

CHARGE PUMP (C1L AND C1H, C2L AND C2H)

These two pairs of terminals, the C1L and C1H and the

C2L and C2H, connect to the external bucket capacitors

required by the internal charge pump. The typical value for

the bucket capacitors is 0.1

µF.

PREDRIVER POWER SUPPLY (CRES)

The CRES terminal is the output of the internal charge

pump. Its output voltage is approximately three times of VDD

voltage. The VCRES voltage is power supply for the internal

predriver circuit of H-Bridges.

POWER GROUND (PGND)

Power ground terminals. They must be tied together on the

PCB.

LOGIC GROUND (LGND)

Logic ground terminal.

17531A Datasheet(PDF) 10 Page - Freescale Semiconductor, Inc

17531A Datasheet(HTML) 10 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Datasheet Download

Link URL