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© 2021 ROHM Co., Ltd.
No.63AN162E Rev.001
February.2021
Application Note
Automotive Power and Motor Drive
40V Max Stepping Motor Driver for Automotive
BD63800MUF-C Application Note
The ROHM BD63800MUF-C is an AEC-Q100 automotive qualified bipolar low-consumption stepping motor driver that is driven by PWM current. It
is suitable for Automotive applications such as LED Headlight, Heat pump, Intake Air Control Valve and Head-up Display. This document describes
how to design the external circuit and PCB layout in order to operate the stepping motor safety and efficiency. Moreover, it guides standard start up
sequence how to set parameter for stall detection and decay mode simply with some attentions.
● Specifications:
BD63800MUF-C operates with single power supply which can simplify the set design.
➢ Absolute maximum supply voltage ……...……………….… 40 V
➢ Recommended operating supply voltage range………….…6.0 to 28 V
➢ Output Current Rating (peak) …..……………………………1.35 A
(Note1)
(Note1)
Pulse width tw ≤ 1 ms, duty 20 %
➢ Output Current Rating (DC) …..………………….................1.20 A
➢ Output On Resistance (Total of upper and lower side) .......0.75 Ω
➢ VCC quiescent supply current (max) ………………………..10 µA
● Features
➢ CLK-IN and SPI-IN Drive mode
➢ Supported stepping Modes: Full step, 1/2, 1/4, 1/8, 1/16 and 1/32 step
➢ Current Decay Mode Switch Function: Fast, Slow, Mix, Auto
- Mix Decay: Linear Adjustment of Slow Decay and Fast Decay Ratio with external pin.
- Auto Decay: Automatic Switch of Slow Decay and Fast Decay.
Further features and protections are referred to the datasheet.
● Application
LED leadlight, Heat pump, Intake Air control, Head-up display etc.
Package W(Typ) x D(typ) x H (Max)
VQFN32FBV050 5.0mm x 5.0mm x 1.0mm
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Application Note
© 2021 ROHM Co., Ltd.
No.63AN162E Rev.001
February.2021
Contents
1. Hardware Peripheral Design ..................................................................................................................................................3
1.1 [VCC] Input capacitor for Power Supply: C_Vcc1 and C_Vcc2 ................................................................ .................................4
1.2 [DIAG1 and DIAG2] Pull-up resistor: R_Diag1 and R_Diag2 ....................................................................................................4
1.3 [MTH] Current Decay Method Setting: R
_Mthv
and R
_Mthg
...........................................................................................................4
1.4 [RREF] Resister for Output Current Level Setting: R
_RREF
........................................................................................................4
1.5 [CR] Chopping Frequency Setting: R
_CR
, C
_CR
.........................................................................................................................6
1.6 [OUT1A, OUT1B, OUT2A, OUT2B] Output: C
_OUT1A
, C
_OUT1B
, C
_OUT2A
, C
_OUT2B
................................ ........................................7
2. PCB Pattern Layout Guideline ................................................................................................................................................8
2.1 VCC (Power Supply Pin): 14 and 27pin ...................................................................................................................................8
2.2 GND (Ground Pin): 12, 20 and 21 pin ......................................................................................................................................8
2.3 OUT1A, OUT1B, OUT2A, OUT2B (H-Bridge Output Pin): 15, 18, 23, and 26pin ......................................................................9
2.4 CR (Chopping Frequency Setting Pin): 29pin ........................................................................................................................ 10
2.5 IC Backside Metal: EXP-PAD ................................................................................................................................................ 10
3. Standard Operate Sequence ................................................................................................................................................ 12
4. Stall Detection Settings ........................................................................................................................................................ 13
5. Decay mode and Chopping frequency Selection .................................................................................................................. 16
5-1. Slow Decay Mode ................................................................................................................................................................ 16
5-2. Fast Decay Mode ................................................................................................................................................................ . 16
5-3. Mix Decay Mode .................................................................................................................................................................. 17
5-4. Auto Decay Mode ................................................................................................................................................................ 17
5-5. Decay mode and Chopping frequency Selection flowchart ................................................................................................ .... 18