DIODES ZXBM1016

ZXBM1016
High efficiency variable speed single-phase fan motor controller
Description
The ZXBM1016 is a high efficiency, low noise,
single-phase, DC brushless motor pre-driver
with PWM variable speed control and current
control suitable for fan and blower motors.
High efficiency and low noise are achieved
using a novel technique (patent pending) for
commutation current control.
The controllers are primarily intended to meet
industry standard OEM fan specifications where
external PWM control are applied, however,
they can also be used with other thermal control
techniques using an external voltage, PWM
signal or thermistor.
Features
Applications
•
•
•
•
•
•
•
•
•
•
•
•
•
Compliant with external PWM speed control
Compliant with thermistor control
Minimum speed setting
High efficiency utilizing tail-end current control
Low noise
Auto restart
Built in Hall amplifier
Hall bias
Speed pulse (FG) output
Integrated current control
Up to 18V input voltage (60V with external regulator)
Small TSSOP20 package
•
•
•
Mainframe and personal computer fans and
blowers
Instrumentation fans
Central heating blowers
Automotive climate control
Applications circuit
D2
12V
D1
1N4004
1N4148
Ph2Hi
H+
Ph1Lo
H-Bias
Ph2Lo
100Ω
R1
470Ω
R2
Ph1Hi
470Ω
R3
C1
1μF
Hall
HR14
R12
1kΩ
R15
4.7kΩ
CONTROL
SPD
R9
12kΩ
Q5
ZXBM1016
SMIN
C4
CPWM
R13
Q6
R18
4.7kΩ
FG
C2
100pF
7&8
R4
1kΩ
4
C6
5&6
W1 7 & 8
2
2.2μF
2
1
1
TSSOP20
SetTh
FG
CLCK
CINT
R11
Range
C3 220kΩ
Gnd
R10
16kΩ
1kΩ
3
Q1-4
ZXMC
3A17DN8
5&6
R7
Sense 33kΩ
0.1μF
R16
4.7kΩ
3
4
100Ω
SetThRef
ThRef
47kΩ
R17
10kΩ
R6
1kΩ
R5
VCC
R8
470Ω
Rsense
0.1Ω
C5
0.47μF
0.47μF
0V
Ordering information - TSSOP20
Device
ZXBM1016ST20TA
ZXBM1016ST20TC
Reel size
(inches)
7 (180mm)
13 (330mm)
Tape width
(mm)
16
16
Quantity
per reel
1000
2,500
Device marking
ZETEX
ZXBM1016
Date code
Issue 1 - February 2007
© Zetex Semiconductors plc 2007
1
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ZXBM1016
Absolute maximum ratings
Parameter
Symbol
Limits
Unit
Supply voltage
VCCmax
-0.6 to 20
V
Input current
ICCmax
200
mA
Maximum input voltage
VImax
-0.6 to VCC+0.5
V
Maximum output voltage
VOmax
-0.6 to VCC+0.5
V
Power dissipation
PDmax
800
mW
Operating temperature
TOPR
-40 to 85
°C
Storage temperature
TSTG
-55 to 125
°C
Electrical characteristics (at Tamb = 25°C and VCC = 12V unless otherwise stated)
Parameter
Symbol
Min.
Typ.
Max. Unit Conditions
Supply
Supply voltage
VCC
Supply current
ICC
6.7
18
15
20
V
For valid ThRef
mA VCC = 12V, no load (*)
Hall connections
Hall amp input voltage
VIN
40
Hall amp common mode voltage VCM
0.5
Hall amp input hysteresis
VOFS
12
Hall amp input current
IBS
Hall bias voltage
VHB
Hall bias output current
IHB
mV diff p-p
VCC-1.5
V
mV
1.5
700
1000
nA
1.75
1.95
V
-10
mA
5.25
V
-10
mA
IHBout = -5mA
Reference voltage
ThRef voltage
VThRef
ThRef output current
IOThRef
4.75
5.0
IOThRef =-10mA
PWM oscillator
CPWM charge current
IPWMC
-5.3
-7
-9.2
␮A
CPWM discharge current
IPWMD
50
75
100
␮A
CPWM high threshold voltage
VTHH
3
V
CPWM low threshold voltage
VTHL
1
V
PWM frequency
FPWM
25
SPD voltage minimum
VSPDL
1
V
100% PWM drive
SPD voltage maximum
VSPDH
3
V
0% PWM drive
SPD input current
IISPD
0.8
2
␮A VIN = 2V
IISMIN
-0.25
-0.5
␮A VIN = 2V
kHz CPWM = 0.1nF
Speed control
Minimum speed setting
SMIN input current
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ZXBM1016
Parameter
Symbol
Min.
Typ.
Max. Unit Conditions
Tail-end current control
Range pin input current setting IRange
range
4
50
␮A
V
Range pin input voltage
VIN
0.50
0.65
0.75
CLCK charge current - lock
ILCKCL
-0.75
-1.42
-1.8
CLCK charge current - run
ILCKCR
CLCK discharge current - lock
ILCKDL
CLCK high threshold voltage
VTHH
5
V
CLCK low threshold voltage
VTHL
1
V
CINT input current - lock
IINTCL
-50
CINT charge current - run
IINTCR
-1
CINT discharge current - run
IINTDR
0.8
␮A Lock mode, VCLCK = 2.5V
␮A Run mode
-(4xIRange)
0.8
Input current = 20␮A
1.25
300n
␮A Lock mode, VCLCK = 2.5V
Lock mode
nA Lock mode, VCLCK = 2.5V
mA Run mode
␮A Run mode
0.8xIRange
Current limit
SetThRef output voltage
VSetThRef ThRef0.5V
SetThRef output current
ISetThRef
Sense input current
ISense
SetTh input current
ISetTh
ThRef0.25V
V
ISetThRef =200␮A
-200
␮A
-20
-100
-20
-100
nA VIN=1V, SetTh=2V
nA VIN=2V, sense=1V
Output drives
Ph1Lo, Ph2Lo output high voltage VOH
VCC–2.2
VCC–1.8
V
IOH =80mA
Ph1Lo, Ph2Lo output low voltage VOLA
0.4
0.6
V
IOL =16mA (†)
Ph1Lo, Ph2Lo output low voltage VOLB
0.4
0.6
V
IOL =50␮A (‡)
IOH
-80
mA
Ph1Lo, Ph2Lo output sink current IOL
80
mA
0.75
V
Ph1Lo, Ph2Lo output source
current
Ph1Hi, Ph2Hi output low voltage
VOLA
0.5
Ph1Hi, Ph2Hi output sink current
IOL
100
mA
Ph1Hi, Ph2Hi off output
leakage current
IOFF
±100
nA
FG output current
IOL
16
mA
FG low level output voltage
VOL
0.5
V
IOL =100mA
Output flag
IOL = 16mA
NOTES:
(*) Measured with pins H+, H-, CLCK and CPWM = 0V and all other signal pins open circuit.
(†) Measured when opposing phase output is low.
(‡) Measured when opposing phase output is high.
Issue 1 - February 2007
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ZXBM1016
Block diagram
Vcc
ThRef
CPWM
Vcc
Ph1 Hi
Vref
Ph2 Hi
Phase
Drive
PWM
Osc
SPD
V SPD
Control
Voltage
Vcc
SMIN
Ph1 Lo
Set Min
Speed
Phase
Drive &
Control
Vcc
CLCK
Ph2 Lo
Locked
Rotor
Detect
Start-up
SetThRef
Range
CINT
Sense
Current
Monitor
Tail-end
Control
Speed
Detect
SetTh
Vcc
H-Bias
Hall
Bias
H+
Hall
H-
Speed &
Lock
Detect
Hall
Amp
FG
Gnd
Pin assignments
Vcc
Ph2Hi
1
H+
Ph1Lo
H-Bias
Ph2Lo
Ph1Hi
HThRef
ZXBM1016
SPD
TSSOP20
© Zetex Semiconductors plc 2007
Sense
SetTh
SMIN
Issue 1 - February 2007
SetThRef
C PWM
FG
CLCK
CINT
Range
Gnd
4
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ZXBM1016
Pin description table
Pin
Type
VCC
Power
The positive supply pin
Description
Gnd
Power
The negative supply pin
ThRef
Reference A 5 volt reference for external networks
H-Bias
Reference A nominal 1.75V reference used as the supply for naked Hall sensors
H+
Input
Hall device positive input. When high in relation to H- Ph2 is active
H-
Input
Hall device negative input
SPD
Input
Speed control input voltage, typically from a PWM integrator or
thermistor.
When low in relation to CPWM the phase low outputs will be turned on
SMIN
Input
Used to set a voltage that represents the minimum speed the motor is to
run at
CPWM
Input
A capacitor on this pin is used to set the PWM frequency
CLCK
Input
A dual use pin used to set the lock and tail-end current control timing.
This will typically be a 470nF capacitor
Range
Input
A resistor is attached between this pin and ThRef to set the device’s
dynamic operating range to the motor’s desired speed range
CINT
Input
A capacitor is attached to this pin for use by the tail-end current control.
This will normally be the same value as that on the CLCK Pin
FG
Output
SetTh
Input
Used to set the threshold voltage that represents the maximum current
to be taken by the motor
Sense
Input
Input for the signal from a sense resistor in the ground return of the
H-bridge driving circuit used to represent the current taken by the motor
Open collector buffered output from the Hall sensor
SetThRef Analogue A variable voltage source used to set the voltage on the SetTh pin
Ph1Hi
Output
Phase 1 high power output to high-side of H-bridge
Ph2Hi
Output
Phase 2 high power output to high-side of H-bridge
Ph1Lo
Output
Phase 1 high power output to low-side of H-bridge
Ph2Lo
Output
Phase 2 high power output to low-side of H-bridge
Operational functional description
Overview
The ZXBM1016 is a high efficiency, low noise, single-phase DC brushless motor pre-driver. It uses
voltage speed control and this voltage can be derived from either a PWM or thermistor source.
The device contains proprietary circuitry to control and limit the current at the end of a
commutation cycle. This tail-end current control (TECC) enables the use of lower rated
components thus providing for a more economic and higher efficiency solution.
The pre-driver also has the usual minimum speed setting and maximum current control
functions.
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ZXBM1016
Control input
The device is controlled from a voltage applied to the SPD pin input. This control voltage can be
derived from an externally generated PWM signal. This signal is converted to a voltage in a
conventional integrator external to the device. Alternatively an external thermistor network can
be used to generate the voltage.
Tail-end current control
To minimize the current at the end of a commutation cycle, the tail current, a proprietary circuit
technique is provided. A number of pins are used to give control over the function. The current is
controlled using the internal PWM function and this acts together with the PWM speed control,
the current control and the start-up function.
Start-up function
The device has a controlled start function prior to the device going into the tail-end current control
mode. This allows the motor to start up at its minimum speed before being allowed to accelerate
to the speed defined by the voltage on the SPD pin.
Device protection
Two levels of protection are provided for fault conditions. The first level of protection is the
conventional lock function. If the motor is stopped or stalled for any reason the motor will enter
the locked rotor condition. In this locked rotor condition the motor speed is set to minimum speed
and the ZXBM1016 will attempt to restart the motor at periodic intervals.
A second level of protection is provided by a current monitor function. An external 100m⍀ sense
resistor is used to detect the current and this is compared with a preset voltage on the SetTh pin.
If the current attempts to rise above the threshold voltage the internal PWM circuit will back-off
the power being delivered to the coil to ensure the maximum is not exceeded.
Pin functional description
H+ - Positive Hall input
H- - Negative Hall input
The rotor position is detected by a Hall sensor, with the output applied to the H+ and H- pins. This
sensor can be either a 4 pin 'naked' Hall device or of the 3 pin buffered switching type. For a 4 pin
device the differential Hall output signal is connected to the H+ and H- pins. For a single-ended
buffered Hall sensor the Hall device output is attached to the H+ pin, with a pull-up attached if
needed. The H- pin has an external potential divider attached to hold the pin at a voltage that is
half of the output swing of the Hall sensor. When H+ is high in relation to H-, Ph2 is the active
drive.
H-Bias - Hall bias output voltage
This is a 1.75V nominal voltage source used to bias a differential unbuffered Hall sensor when
that type is being utilized.
ThRef - External network reference
This is a reference voltage of nominal 5V and is used by external networks to set up the SPD and
SMIN pins control voltages.
It is designed for the ability to 'source' current and therefore it will not 'sink' any current from a
higher voltage. The total current drawn from the pin by the minimum speed potential divider
network and any other voltage setting network should not exceed 10mA.
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ZXBM1016
SPD - Speed control input
The voltage applied to the SPD pin provides control over the fan motor speed by varying the Pulse
Width Modulated (PWM) drive ratio at the Ph1Lo and Ph2Lo outputs. The input voltage range for
the control signal is 3V to 1V, representing 0% to 100% drive respectively.
If variable speed control is not required this pin can be left with an external potential divider to
set a fixed speed or tied through a 10k⍀ resistor to ground to provide full speed i.e. 100% PWM
drive.
The advantage of a fixed potential divider is that the benefit of the current limit and tail-end
current control can be achieved. Neither function will operate with the pin tied directly to ground.
If full speed with current limit and tail-end current control is required then connect the SPD pin
ground through a 10k⍀ resistor with a 0.1␮F capacitor in parallel. This capacitor is used for the
tail-end current control shaping.
If required this pin can also be used as an enable pin. The application of a voltage >3.0V will force
the PWM drive fully off, in effect disabling the drive.
SMIN - Minimum speed threshold voltage
A voltage can be set on this pin using a potential divider between the ThRef and Gnd. This voltage
is monitored by the SPD pin such that the SPD voltage cannot rise above the SMIN voltage. As a
higher voltage on the SPD pin represents a lower speed it therefore restricts the lower speed
range of the motor. If this feature is not required the pin is left tied to ThRef so no minimum speed
will be set.
If the fan is being controlled from an external voltage source and the minimum speed feature is
required then a 10k⍀ resistor should be placed in series with the external control voltage and the
SPD pin.
CLCK - Locked rotor and run mode timing capacitor
The CLCK pin will have a capacitor connected to ground. It is a dual function pin providing timing
whilst running and when in the lock condition.
When a motor is running under normal conditions this pin provides a triangular waveform related
to the speed of the motor. This waveform is used by the tail-end current control circuit to
determine the end of the commutation cycle.
If the fan stops rotating for any reason then this pin takes on the conventional operation of a
Locked Rotor monitor. In this condition and after the motor has stopped, a predetermined time
(TOFF) will elapse during which the motor will not be driven. After this delay the circuitry uses a
defined period (TON) to attempt to re-enable the output drive by going through a start-up routine
in an attempt to re-start the fan. This cycle of (TOFF) and (TON) will be repeated indefinitely or until
the fan re-starts.
The cycle of (TOFF) and (TON) is also used to start the fan from power-up and so this pin forms a
start-up function in conjunction with the current monitor circuit described towards the end of this
section.
The time period of (TOFF) and (TON) is determined by the value of capacitor applied to the CLCK
pin. Any selection of the value will need consideration when in the run and lock modes. Typically
a 0.47␮F will provide for most applications.
Issue 1 - February 2007
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ZXBM1016
CINT - Integrator timing capacitor
A capacitor is connected from this pin to ground. It is used to store a signal that is proportional
to the commutation period. The stored signal is a representation of the motor speed and is used
by the tail-end control circuitry. It will normally be the same value as that applied to the CLCK pin.
Range - Speed range setting pin
The ZXBM1016 is designed to operate over a predefined dynamic range. This will normally be in
excess of 10:1 i.e. the lowest speed will be 1/10 of the full speed. In some instance the speed range
might be 200rpm to 2,000rpm yet in others it could be 1,000 to 10,000rpm. This pin allows the tailend current control operation to be tuned to the desired speed range. To do this a resistor is
attached between the range pin and the ThRef pin.
CLCK peak voltage (V)
The following graph gives a range of resistor values against the speed range.
5.0
RRange
4.5
120kΩ
4.0
220kΩ
3.5
360kΩ
3.0
470kΩ
2.5
2.0
1.5
1.0
0.5
750kΩ
0.0
0
2000
4000
CLCK = 0.47μF
6000
8000
10000
Speed (rpm)
Speed vs CLCK peak voltage
Typically a 220k⍀ resistor will cover most mid speed range motors of 600rpm to 6,000rpm,
however a lower value can be used to enable the motor to be run at higher speeds. Conversely a
higher value will be needed for motors running at a lower speed range.
CPWM - Sets PWM frequency
This pin has an external capacitor attached to set the PWM frequency for the phase drive outputs.
A capacitor value of 0.1nF will provide a PWM frequency of typically 25kHz.
FG - Frequency generator (speed)
This is the frequency generator output and is a buffered signal from the Hall sensor.
This is an open collector drive giving an active pull down with the high level being provided by
an external pull up resistor.
Ph1Lo and Ph2Lo - Low-side external H-bridge driver
These pair of outputs drive the low side of the external power device H-bridge that in turn drives
the single phase winding. These outputs provide both the commutation and PWM waveforms.
The outputs are active pull-up and active pull-down to help faster switching off when driving
MOSFET devices with a high gate capacitance. When in the high state the outputs will provide up
to 80mA of drive into the base or gates of external transistors as shown in the typical application
circuit shown on the front page.
When in the low state the active phase drive is again capable of sinking up to 80mA to aid turn
off times during PWM operation. When the phase is inactive the output is held low by a 7.5k⍀
internal pull-down resistor.
Issue 1 - February 2007
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ZXBM1016
Ph1Hi and Ph2Hi - High-side external H-bridge driver
These are the high side outputs to the external H-bridge and are open collector outputs capable
of sinking 100mA. This signal provides commutation only to the H-bridge.
GND - Circuitry ground return
This is the device supply ground return pin and will generally be the most negative supply pin to
the fan.
VCC - Circuitry applied voltage
This provides the supply for the device's internal circuitry and for the H-bridge output stage.
Sense - Current control sense
This pin is used by the current sensing circuit to monitor the current taken by the motor windings.
The signal comes from a sense resistor in the low-side ground return of the external H-bridge
driver.
SetTh - Current control threshold voltage
This pin is used by the current sensing circuit as the reference voltage for the voltage on the sense
pin to be compared against. If the voltage on the sense pin starts to exceed the voltage set on this
pin the current control circuitry starts to back off the PWM voltage and thus the current being
supplied to the motor coil.
SetThRef - SetTh and start-up reference
This pin is derived from an internal start-up circuit and is used as the source voltage for the
potential divider network attached to the SetTh pin.
Under running conditions this will be a voltage of approximately 4.75V, however, during start up
the voltage ramps up from 0V to 4.75V at a rate determined by the capacitor on the CLCK pin. Once
the motor is running it will go to its steady state.
This is a low power output capable of supplying a maximum of 200␮A. It should only be used to
supply the potential divider network attached to the SetTh pin.
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ZXBM1016
Intentionally left blank
Issue 1 - February 2007
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ZXBM1016
Package outline - TSSOP20
D
E1 E
L
c
A2 A
b
Dim.
A
A1
A2
D
E
L
e
b
c
e
A1
Millimeters
Min.
Max.
1.20
0.05
0.15
0.80
1.05
6.40
6.60
6.40 BSC
0.45
0.75
0.65 BSC
0.19
0.30
0.09
0.20
Inches
Min.
Max.
0.047
0.002
0.006
0.031
0.041
0.252
0.260
0.252 BSC
0.018
0.030
0.026 BSC
0.007
0.012
0.004
0.008
Note: Controlling dimensions are in millimeters. Approximate dimensions are provided in inches
Issue 1 - February 2007
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ZXBM1016
Definitions
Product change
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service. Customers are solely responsible for obtaining the latest relevant information before placing orders.
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The circuits in this design/application note are offered as design ideas. It is the responsibility of the user to ensure that the circuit is fit for
the user’s application and meets with the user’s requirements. No representation or warranty is given and no liability whatsoever is
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opportunity or consequential loss in the use of these circuit applications, under any circumstances.
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1. are intended to implant into the body
or
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“Preview”
Future device intended for production at some point. Samples may be available
“Active”
Product status recommended for new designs
“Last time buy (LTB)”
Device will be discontinued and last time buy period and delivery is in effect
“Not recommended for new designs” Device is still in production to support existing designs and production
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Production has been discontinued
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This term denotes a very early datasheet version and contains highly provisional information, which
may change in any manner without notice.
“Provisional version”
This term denotes a pre-release datasheet. It provides a clear indication of anticipated performance.
However, changes to the test conditions and specifications may occur, at any time and without notice.
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