AH5794

AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Description
Pin Assignments
The AH5794 is a single chip solution for driving single-coil
brushless direct current (BLDC) fans and motors. The
integrated full-bridge driver output stage uses soft switching to
minimize audible switching noise and electromagnetic
interference (EMI) providing a low noise solution.
(Top View)
NEW PRODUCT
Low operating voltage down to 1.8V allows motor speed to be
controlled by varying the supply voltage.
FG
1
6
NC
VSS
2
5
VDD
O2
3
4
O1
TSOT26
To help protect the motor coil, the AH5794 provides Rotor
Lock Protection which shuts down the output drive if rotor lock
is detected. The device automatically re-starts when the rotor
lock is removed. Over temperature shutdown provides
thermal protection for the device.
(Top View)
A Tachometer output is provided by open-drain Frequency
Generator (FG) Pin which allows external interface to monitor
motor rotation or speed. The FG output is the magnetic
change frequency.
NC 1
6 FG
VDD 2
5 O2
O1 3
4 VSS
U-DFN2020C-6
The AH5794 is available in space saving and low profile
TSOT26 and U-DFN2020C-6 packages.
Features
Applications
•
Supports single-coil full-wave BLDC fan drivers
•
3V/ 3.3V/ 5V BLDC Cooling Fans
•
Built-in Hall sensor and input amplifier
•
Netbook/ Notebook BLDC fans
•
Operating voltage: 1.8V to 6V
•
Instruments cooling fans
•
VDD voltage speed control
•
Low Voltage/ Low Power BLDC Motors
•
Soft switching for low noise DC fan motor applications
•
Rotor Lock Protection (Lock detection, output shutdown
and automatic re-start)
•
Thermal protection
•
Tachometer (FG) output
•
No external timing capacitor - Reduces the numbers of
external components required
•
Low profile package: TSOT26 and U-DFN2020C-6
•
Halogen and Antimony free “Green” packages.
•
Lead Free Finish/ RoHS Compliant
AH5794
Document number: DS35809 Rev. 1 - 2
1 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
NEW PRODUCT
Typical Application Circuit
Pin Descriptions
Pin Name
VDD
Notes:
Description
Power supply pin
VSS
Ground pin
O1
Output driving & sinking pin
O2
Output driving & sinking pin
NC
No connection
FG
Frequency generator (Note 1)
1. The FG output is the same as the magnetic change frequency.
AH5794
Document number: DS35809 Rev. 1 - 2
2 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
NEW PRODUCT
Functional Block Diagram (Note 2)
Notes:
2.The AH5794 has an open-drain tachometer FG output that follows the magnetic change frequency. Typically a pull-up resistor of 10kΩ is
recommended from FG pin to the supply voltage.
AH5794
Document number: DS35809 Rev. 1 - 2
3 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Absolute Maximum Ratings (TA = 25°C, unless otherwise noted, Note 3)
Symbol
VDD
IO(PEAK)
NEW PRODUCT
PD
TST
ESD HBM
Notes:
Characteristics
Values
Unit
7
V
1000
mA
Supply Voltage
Maximum Output Current (Peak)
TSOT26
Power Dissipation
650
U-DFN2020C-6
750 (Note 4)
Storage Temperature Range
-65 ~ +150
Human Body Model ESD Protection
4
mW
o
C
kV
3. Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are stress ratings only;
functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability
may be affected by exposure to absolute maximum rating conditions for extended periods of time
4. U-DFN2020C-6 exposed pad soldered to minimum recommended landing pads (see Package Outline Dimension section) on a two-layer 2oz.
copper FR4 PCB (1.6mm thickness) with no thermal vias in exposed PADs or any copper flood connecting to the landing pattern of the
exposed pad.
Recommended Operating Conditions (TA = 25°C)
Symbol
VDD
TA
Parameter
Conditions
Supply Voltage at VDD pin
DC supply speed control mode
Operating Ambient Temperature Range
Operating
Min
Max
1.8
6.0
Unit
V
o
C
-40
+105
Min
Typ.
Max
Unit
-
2.2
-
mA
IOUT = 300mA
4.70
4.88
-
V
IOUT = 500mA
4.5
4.8
-
V
IOUT = 300mA
-
0.12
0.3
V
IOUT = 500mA
-
0.2
0.5
V
0.5
V
Electrical Characteristics (TA = 25°C, VDD = 5V)
Symbol
Characteristics
IDD
Supply Current
VOH
Output Voltage High
VOL
Output Voltage Low
Conditions
No Load
VOH +VOL
Output voltage of N- and PMOS
combined
IOUT = 300mA
0.3
IOUT = 500mA
0.5
TSW
Output Switching Slope Duration
17Ω load on O1/O2
-
IFG = 5mA
350
-
ILEAK
FG Output Leakage Current
VFGOL
FG Output Voltage Low
TON
On Time
RDR
Duty Ratio
TOFF / TON
V
-
μs
-
5
μA
-
0.4
V
500
650
ms
10
-
200
TJ_SDN_TH
IC junction temperature thermal
shutdown threshold
175
o
C
TJ_SDN_HYST
IC junction temperature thermal
shutdown hysteresis
25
o
C
AH5794
Document number: DS35809 Rev. 1 - 2
4 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Magnetic Characteristics (TA = 25°C, VDD = 1.8V to 6V, Note 5)
(1mT = 10 G)
Notes:
Parameter
Min
Typ.
Max
BOP
Operate Point
10
25
50
BRP
Release Point
-50
-25
-10
Bhy
Hysteresis
-
50
-
Unit
Gauss
5. Magnetic characteristics may vary with supply voltage, operating temperature and after soldering.
Operating Characteristics
O1
O2
VOH
VOH
RP
OFF
ON
OP
Output Voltage in Volts
Output Voltage in Volts
NEW PRODUCT
Symbol
VOL
Brp
0
OFF
OP
RP
ON
VOL
Bop
Brp
Magnetic Flux Density in Gauss
0
N
S
Marking side
Marking side
N
S
(U-DFN2020C-6)
(TSOT26)
AH5794
Document number: DS35809 Rev. 1 - 2
Bop
Magnetic Flux Density in Gauss
5 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Operating Characteristics (Note 6, 7, 8 and 9)
Magentic
S
N
NEW PRODUCT
O2
O1
Ton
FG
Toff
Mechanical lock
Normal spinning
motor locked detected
“Re-start spinning”
motor locked cleared
Truth Table
Notes:
O1
O2
FG
L
H
L
H
L
H
L
L
X
(Note 9)
6. In “Normal spinning, the FG changes its state at each edge of O1.
7. When the motor locks with South pole at the Hall element, O2 is kept on “L” and O1 is a clock with Ton/Toff ratio.
When motor locks with North pole at the Hall element, O1 is kept on “L”, O2 is a clock with Ton/Toff ratio.
8. When “Re-start spinning” occurs, the motor speed ramps up to the “Normal Spinning” speed from zero.
Speed ramp-up profile depends on motor characteristics.
9. X: H or L depends on magnetic pole North or South
AH5794
Document number: DS35809 Rev. 1 - 2
6 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Application Note
Motor Speed Control
DC Supply Voltage (VDD) Speed Control
Motor speed can be controlled by varying the VDD supply voltage between 1.8V to 6V.
NEW PRODUCT
With 5V nominal motor, changing VDD voltage between 5V to 1.8V, speed can be controlled from 100% to 36% typically.
Soft Switching
AH5794 uses soft switching of the motor coil current during commutation for to minimize audible switching noise and
electromagnetic interference (EMI) to provide a low noise solution.
Vdd
Vout 1
Vout 2
Vss
200µs typ.
AH5794
Document number: DS35809 Rev. 1 - 2
7 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Thermal Performance Characteristics
TA (°C)
25
50
60
70
75
80
85
90
95
100
PD (mW)
651
521
469
417
391
365
339
313
286
260
TA (°C)
105
110
115
120
125
130
135
140
145
150
PD (mW)
234
208
182
156
130
104
78
52
26
0
POWER DISSIPATION (mW)
NEW PRODUCT
(1) Package type: TSOT26
700
650
600
500
400
300
200
100
0
-40
25
50
75
100 105
125
150
TEMPERATURE (°C)
Power Dissipation Curve
AH5794
Document number: DS35809 Rev. 1 - 2
8 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Thermal Performance Characteristics (cont.)
(2) Package type: U-DFN2020C-6 (Note 10)
25
50
60
70
75
80
85
90
95
100
PD (mW)
781
625
563
500
469
438
406
375
344
313
TA (°C)
105
110
115
120
125
130
135
140
145
150
PD (mW)
281
250
219
188
156
125
94
63
31
0
NEW PRODUCT
TA (°C)
900
POWER DISSIPATION (mW)
800
700
600
500
400
300
200
100
0
-40
25
50
75
100 105
125
150
TEMPERATURE (°C)
Power Dissipation Curve
Notes:
10. U-DFN2020C-6 exposed pad soldered to minimum recommended landing pads (see Package Outline Dimension section) on a two-layer 2oz.
copper FR4 PCB (1.6mm thickness) with no thermal vias in exposed PADs or any copper flood connecting to the landing pattern of the
exposed pad.
AH5794
Document number: DS35809 Rev. 1 - 2
9 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Ordering Information
NEW PRODUCT
AH5794 - XXX - 7
Package
Packing
WU : TSOT26
FDC : U-DFN2020C-6
7 : Tape & Reel
7” Tape and Reel
Package
Code
Packaging
(Note 11 & 12)
Quantity
Part Number Suffix
AH5794-WU-7
WU
TSOT26
3000/Tape & Reel
-7
AH5794-FDC-7
FDC
U-DFN2020C-6
3000/Tape & Reel
-7
Device
Notes:
11. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at
http://www.diodes.com/datasheets/ap02001.pdf
12. EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. No purposely added lead. Halogen and Antimony free.
Please visit our website at http://www.diodes.com/products/lead_free.html
Marking Information
(1) Package type: TSOT26
Part Number
Package
Identification Code
AH5794-WU-7
TSOT26
J4
(2) Package type: U-DFN2020C-6
( Top View )
XX
YWX
XX : Identification Code
Y : Year : 0~9
W : Week : A~Z : 1~26 week;
a~z : 27~52 week; z represents
52 and 53 week
X : A~Z : Internal code
Part Number
Package
Identification Code
AH5794-FDC-7
U-DFN2020C-6
J4
AH5794
Document number: DS35809 Rev. 1 - 2
10 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Package Outline Dimensions (All Dimensions in mm)
NEW PRODUCT
(1) Package type: TSOT26
(2) Package Type: U-DFN2020C-6
0.15max.
0.15 C
B
2x-
A
6x-0.37
0.57/0.63
0.30±0.1
15
0.86/1.06
1.95/2.075
R0.
1.95/2.075
1.55/1.75
Seating plane
C
0.30/0.40
Pin#1 ID
2x
0/0.05
0.08 C
(Active area depth)
Die
1
R0.
0.9
Top Mark
0.05 C
6x-0.45
0.55±0.1
0.43mon.
1.0±0.1
0.57/0.63
Hall Sensor
0.65
1.59
0.15 C
0.65nom.
0.2/0.3
0.05 M C A B
Land Pattern Recommendation
(Unit:mm)
Top View
Bottom View
AH5794
Document number: DS35809 Rev. 1 - 2
11 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
Taping Orientation
NEW PRODUCT
(1) Package Type: U-DFN2020C-6
Notes:
11. The taping orientation of the other package type can be found on our website at http://www.diodes.com/datasheets/ap02007.pdf.
AH5794
Document number: DS35809 Rev. 1 - 2
12 of 13
www.diodes.com
March 2012
© Diodes Incorporated
AH5794
SINGLE PHASE HALL EFFECT LATCH FAN MOTOR DRIVER
IMPORTANT NOTICE
DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS
DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION).
NEW PRODUCT
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other
changes without further notice to this document and any product described herein. Diodes Incorporated does not assume any liability
arising out of the application or use of this document or any product described herein; neither does Diodes Incorporated convey any
license under its patent or trademark rights, nor the rights of others. Any Customer or user of this document or products described
herein in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all the companies
whose products are represented on Diodes Incorporated website, harmless against all damages.
Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized
sales channel.
Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall
indemnify and hold Diodes Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees
arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized application.
Products described herein may be covered by one or more United States, international or foreign patents pending. Product names
and markings noted herein may also be covered by one or more United States, international or foreign trademarks.
LIFE SUPPORT
Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without
the express written approval of the Chief Executive Officer of Diodes Incorporated. As used herein:
A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body, or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided
in the labeling can be reasonably expected to result in significant injury to the user.
B.
A critical component is any component in a life support device or system whose failure to perform can be reasonably expected
to cause the failure of the life support device or to affect its safety or effectiveness.
Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or
systems, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements
concerning their products and any use of Diodes Incorporated products in such safety-critical, life support devices or systems,
notwithstanding any devices- or systems-related information or support that may be provided by Diodes Incorporated. Further,
Customers must fully indemnify Diodes Incorporated and its representatives against any damages arising out of the use of Diodes
Incorporated products in such safety-critical, life support devices or systems.
Copyright © 2012, Diodes Incorporated
www.diodes.com
AH5794
Document number: DS35809 Rev. 1 - 2
13 of 13
www.diodes.com
March 2012
© Diodes Incorporated