|
|
零件编号 | 3977 | ||
描述 | MICROSTEPPING DMOS DRIVER WITH TRANSLATOR | ||
制造商 | Allegro MicroSystems | ||
LOGO | |||
1 Page
3977
A3977xED
(PLCC)
NC 7
6 5 4 3 2 1 44 43 42 41 40
VBB1
NC 8
PFD 9
RC1 10
PWM
TIMER
GND 11
GND 12
GND 13
REF 14
÷8
REG
RC2 15
LOGIC
SUPPLY
16
VDD
NC 17
VBB2
18 19 20 21 22 23 24 25 26 27 28
39 NC
38 CP2
37 CP1
36 VCP
35 GND
34 GND
33 GND
32 VREG
31 STEP
30 NC
29 NC
Dwg. PP-075-1
ABSOLUTE MAXIMUM RATINGS
at TA = +25°C
Load Supply Voltage, VBB ............. 35 V
Output Current, IOUT .................. ±2.5 A*
Logic Supply Voltage, VDD ........... 7.0 V
Logic Input Voltage Range, VIN
(tw >30 ns) ..... -0.3 V to VDD + 0.3 V
(tw <30 ns) ........... -1 V to VDD + 1 V
Sense Voltage, VSENSE ................. 0.5 V
Reference Voltage, VREF ................ VDD
Package Power Dissipation,
PD................................. See page 3
Operating Temperature Range, TA
(A3977Kx) ............ -40°C to +125°C
(A3977Sx) .............. -20°C to +85°C
Junction Temperature, TJ ......... +150°C
Storage Temperature Range,
TS ......................... -55°C to +150°C
* Output current rating may be limited by
duty cycle, ambient temperature, and heat
sinking. Under any set of conditions, do not
exceed the specified current rating or a
junction temperature of 150°C.
MICROSTEPPING DMOS DRIVER
WITH TRANSLATOR
The A3977xED and A3977xLP are complete microstepping motor drivers
with built-in translator. They are designed to operate bipolar stepper motors in
full-, half-, quarter-, and eighth-step modes, with output drive capability of 35
V and ±2.5 A. The A3977 includes a fixed off-time current regulator that has
the ability to operate in slow-, fast-, or mixed-decay modes. This current-
decay control scheme results in reduced audible motor noise, increased step
accuracy, and reduced power dissipation.
The translator is the key to the easy implementation of the A3977. By
simply inputting one pulse on the STEP input the motor will take one step
(full, half, quarter, or eighth depending on two logic inputs). There are no
phase-sequence tables, high-frequency control lines, or complex interfaces to
program. The A3977 interface is an ideal fit for applications where a complex
µP is unavailable or over-burdened.
Internal synchronous-rectification control circuitry is provided to improve
power dissipation during PWM operation.
Internal circuit protection includes thermal shutdown with hysteresis,
under-voltage lockout (UVLO) and crossover-current protection. Special
power-up sequencing is not required.
The A3977 is supplied in a choice of two power packages, a 44-pin
plastic PLCC with copper batwing tabs (suffix ED), and a thin (<1.2 mm), 28-
pin TSSOP with an exposed thermal pad (suffix LP). The SLP package is
available in a lead-free version (100% matte tin leadframe).
FEATURES
■ ±2.5 A, 35 V Output Rating
■ Low rDS(on) Outputs, 0.45 Ω Source, 0.36 Ω Sink Typical
■ Automatic Current Decay Mode Detection/Selection
■ 3.0 V to 5.5 V Logic Supply Voltage Range
■ Mixed, Fast, and Slow Current Decay Modes
■ Home Output
■ Synchronous Rectification for Low Power Dissipation
■ Internal UVLO and Thermal Shutdown Circuitry
■ Crossover-Current Protection
Always order by complete part number:
Part Number
A3977KED
A3977KLP
A3977SED
A3977SED-T
A3977SLP
A3977SLP-T
Package
44-pin PLCC
28-pin TSSOP
44-pin PLCC
44-pin PLCC; Lead-free
28-pin TSSOP
28-pin TSSOP; Lead-free
3977
MICROSTEPPING DMOS DRIVER
WITH TRANSLATOR
Functional Description (cont’d)
Synchronous Rectification. When a PWM off cycle
is triggered by an internal fixed off-time cycle, load
current will recirculate according to the decay mode
selected by the control logic. The A3977 synchronous
rectification feature will turn on the appropriate
MOSFETs during the current decay and effectively short
out the body diodes with the low rDS(on) driver. This will
reduce power dissipation significantly and eliminate the
need for external Schottky diodes for most applications.
The synchronous rectification can be set in either
active mode or disabled mode.
Active Mode. When the SR input is logic low, active
mode is enabled and synchronous rectification will occur.
This mode prevents reversal of the load current by turning
off synchronous rectification when a zero current level is
detected. This prevents the motor winding from conduct-
ing in the reverse direction.
Disabled Mode. When the SR input is logic high,
synchronous rectification is disabled. This mode is
typically used when external diodes are required to
transfer power dissipation from the A3977 package to the
external diodes.
Timing Requirements
(TA = +25°C, VDD = 5 V, Logic Levels are VDD and Ground)
STEP
MS1/MS2/
DIR/RESET
50%
AB
C
D
E
SLEEP
A. Minimum Command Active Time
Before Step Pulse (Data Set-Up Time) ..... 200 ns
B. Minimum Command Active Time
After Step Pulse (Data Hold Time) ............ 200 ns
C. Minimum STEP Pulse Width ...................... 1.0 µs
D. Minimum STEP Low Time ......................... 1.0 µs
E. Maximum Wake-Up Time ......................... 1.0 ms
Dwg. WP-042
8
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
3977
MICROSTEPPING DMOS DRIVER
WITH TRANSLATOR
A3977xED
28
18
0.319
0.291
0.021
0.013
0.319
0.291
0.050
BSC
29
0.032
0.026
0.695
0.685
0.656
0.650
39
0.020
MIN
0.180
0.165
40
28
17
INDEX AREA
Dimensions in Inches
(controlling dimensions)
7
44 1 2
0.656
0.650
0.695
0.685
6
Dwg. MA-005-44A in
18
8.10
7.39
0.533
0.331
8.10
7.39
1.27
BSC
29
0.812
0.661
17.65
17.40
16.662
16.510
39
17
INDEX AREA
Dimensions in Millimeters
(for reference only)
7
40 44 1 2
6
0.51
MIN
4.57
4.20
16.662
16.510
17.65
17.40
Dwg. MA-005-44A mm
NOTES: 1. Exact body and lead configuration at vendor’s option within limits shown.
2. Lead spacing tolerance is non-cumulative.
3. Webbed lead frame. Terminals 1, 2, 11, 12, 13, 22, 23, 24, 33, 34, 35, and 44 are internally one piece.
4. Supplied in standard sticks/tubes of 27 devices or add “TR” to part number for tape and reel.
16
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
|
|||
页数 | 18 页 | ||
下载 | [ 3977.PDF 数据手册 ] |
零件编号 | 描述 | 制造商 |
3970 | 3970-Type 1550 nm Transmitter | Agere Systems |
3971 | DUAL DMOS FULL-BRIDGE DRIVER | Allegro MicroSystems |
3972 | DUAL DMOS FULL-BRIDGE MICROSTEPPING PWM MOTOR DRIVER | Allegro MicroSystems |
3973 | DUAL DMOS FULL-BRIDGE MICROSTEPPING PWM MOTOR DRIVER | Allegro MicroSystems |
零件编号 | 描述 | 制造商 |
STK15C88 | 256-Kbit (32 K x 8) PowerStore nvSRAM | Cypress Semiconductor |
NJM4556 | DUAL HIGH CURRENT OPERATIONAL AMPLIFIER | New Japan Radio |
EL1118-G | 5 PIN LONG CREEPAGE SOP PHOTOTRANSISTOR PHOTOCOUPLER | Everlight |
DataSheet8.cn | 2020 | 联系我们 | 搜索 | Simemap |