Datasheet UDN3626M, UDN3625M Datasheet (Allegro)

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for availability

and latest information

ABSOLUTE MAXIMUM RATINGS

3625

AND

3626

POWERHALL® SENSOR/DRIVERS

FOR BRUSHLESS DC MOTORS

Requiring a minimum of external components, the UDN3625M
and UDN3626M are monolithic ICs that provide single-chip control
and direct drive solutions for many small, single-phase, unipolar
brushless dc motor applications. Integrated into the ICs are a high­sensitivity Hall-effect sensor, control and commutating logic, a stable
voltage regulator, extensive self and system protective functions, and
two high-current saturated npn outputs. Both ICs include thermal
shutdown, output over-current limiting, and output transient protection/
flyback diodes. The UDN3625M is nominally for 12 V motor applica­tions while the UDN3626M is better suited to 24 V motors.

Output over-current limiting (relating to startup surge or a locked
rotor condition) and short-circuit protection are provided by an internal
current-sense resistor. The maximum (default) output load current is
typically 1.3 A for the UDN3625M or 600 mA for the UDN3626M,
but may be decreased by user selection of an external low-wattage
resistor.

A separate low-level output provides tachometer capability for
motor speed control or sensing a locked rotor condition. With appro­priate external logic, pulse-width modulated (PWM) speed control can
be accomplished at the output current adjust pin.

Data Sheet

27690A

Supply Voltage, VCC. . . . . . . . . . See Table

Output Current, I
PWM Current Control Voltage,

V

. . . . . . . . . . . . . See Applications

ADJ

Magnetic Flux Density, B . . . . . . Unlimited

Package Power Dissipation,

. . . . . . . . . . . . . . . . . . . . See Graph

P

D

Operating Temperature Range,

. . . . . . . . . . . . . . . . . -20°C to +85°C

T

A

Storage Temperature Range,

TS. . . . . . . . . . . . . . . . -65°C to +150°C

V

CC(MAX)

I

O(CONT)

I

O(PEAK)

Output current rating will be limited by
ambient temperature, supply voltage, and
duty cycle. Under any set of conditions, do
not exceed a junction temperature of
+150°C.

. . . . . . . . . . . . See Table

O

UDN3625M UDN3626M

14 V 26 V

1.0 A 0.45 A

1.6 A 0.75 A

These sensor/drivers are supplied in an 8-pin mini-DlP plastic
package with a copper leadframe for increased package power
handling capability.

FEATURES

■ 900 mA/12 V or 400 mA/24 V Operation

■ Speed-Control (PWM) Capability

■ Locked-Rotor Indication

■ Minimum External Components

■ Over-Current Protected

■ Thermal Protection

■ Enhanced Reliability

■ Reduced Cost

Always order by complete part number, e.g., UDN3625M .
See Maximum Ratings at left.

3625

POWERHALL

AND

3626

®

SENSOR/DRIVERS FOR
BRUSHLESS DC MOTORS

REG.

X

7

GROUND

TSD

FUNCTIONAL BLOCK DIAGRAM

SUPPLY

5

OUT

4

6

OUT

A

8

TACH

OUT

V

S

B

+V

2.0

R = 55°C/W

θJC

1.5

1.0

0.5

0

25

ALLOWABLE PACKAGE POWER DISSIPATION IN WATTS

FREE AIR, R = 80°C/W

50 75 100 125 150

θJA

TEMPERATURE IN °C

Dwg. GP-009-1B

PWM/I
ADJUST

1

O

R

ADJ

TRUTH TABLE

Mag. Field PWM/IOADJ OUTAOUT

> +B

OP

> -B

OP

Any <0.3 V High High

Open Low High
Open High Low

Dwg. FP-005-1

B

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
Copyright © 1988, 1995, Allegro MicroSystems, Inc.

3625

AND

3626

POWERHALL

®

SENSOR/DRIVERS FOR

BRUSHLESS DC MOTORS

ELECTRICAL CHARACTERISTICS at T

= +25°C, R

A

= ∞, Over Operating Voltage Range

ADJ

(unless otherwise noted).

Limits
Characteristic Symbol Test Conditions Min. Typ. Max. Units
UDN3625M

Operating Voltage Range V
Output Leakage Current I
Output Breakdown Voltage V
Output Saturation Voltage V

S

O

(BR)CEX

O(SAT)

Output Current Limit IO MAX R
Output Clamp Voltage

V

CL

(Test Fig. 1)

Output Switching Time t
Supply Current

PLH

l

CC

(Test Fig. 2)

UDN3626M

VCC = VO = 24 V — — 100 µA
VCC = 24 V, lO = 10 mA* 34 — — V
IO = 450 mA, VS = 6.5 V — 0.25 0.4 V
IO = 900 mA, VS = 12 V — 0.5 0.8 V

= ∞, VO = 2 V 1.0 1.3 1.6 A

ADJ

ICL = 10 mA, VCC = 0 11 12 13 V
ICL = 450 mA=, VCC = 0 13 14 15 V
50% V
R

ADJ

R

ADJ

to VO = 3.0 V, lO = 450 mA — — 5.0 µs

ADJ

= ∞, VS = 14 V, One Output ON — 30 38 mA
= 0 Ω, VS = 14 V, Outputs OFF — 8.0 10 mA

6.5 12 14 V

Operating Voltage Range V
Output Leakage Current l
Output Breakdown Voltage V
Output Saturation Voltage V

S

O

(BR)CEX

O(SAT)

VCC = VO = 30 V — — 100 µA
VCC = 30 V, lO = 10 mA* 50 — — V
lO = 250 mA, VS = 6.5 V — 0.15 0.3 V

lO = 400 mA, VS = 24 V — 0.3 0.5 V
Output Current Limit lOMAX R
Output Clamp Voltage

V

CL

(Test Fig. 1)

Output Switching Time t
Supply Current l

PLH

CC

(Test Fig. 2)

= ∞, VO = 2 V 450 600 750 mA

ADJ

ICL = 10 mA, VCC = 0 17 18 20 V

ICL = 250 mA, VCC = 0 19 20 22 V

50% V

R

ADJ

R

ADJ

to VO = 3.0 V, lO = 250 mA — — 5.0 µs

ADJ

= ∞, VS = 26 V, One Output ON — — 24 mA
= 0 Ω, VS = 26 V, Outputs OFF — 8.0 10 mA

*lO is almost entirely Zener clamp current.
† Pulse test.
‡ Dependent on value of external series Zener diode (see Applications), 6.5 V without a Zener diode.

‡2426 V

Continued next page...

3625

POWERHALL

AND

3626

®

SENSOR/DRIVERS FOR
BRUSHLESS DC MOTORS

ELECTRICAL CHARACTERISTICS continued

Limits
Characteristic Symbol Test Conditions Min. Typ. Max. Units
Both

Operate Point§ B
Hysteresis B
Output Current Limit Ratio lO/lO MAX R

PWM Control Current I
Tach Output Leak. Current I
Tach Output Sat. Voltage V
Thermal Shutdown T
Thermal Hysteresis ∆T

OP

H

ADJ

T

T(SAT)

J

J

= 39 kΩ — 0.75 — —

ADJ

R

= 17 kΩ — 0.50 — —

ADJ

R

= 10 kΩ — 0.25 — —

ADJ

V

= 0 — -350 -500 µA

ADJ

V

= 14 V — — 10 µA

T

IT = 750 µA — 0.2 0.4 V

— ±100 ±150 G
— 200 — G

–– 165 — °C
–– 10 — °C

§ Magnetic flux density is measured at most sensitive area of device, nominally located 0.055" (1.40 mm) below the top of the package.

OUTPUT CLAMP VOLTAGE TEST

SUPPLY CURRENT TEST

(ONE OUTPUT TESTED AT A TIME)

Dwg. No. EP-013

TEST FIG. 2 TEST FIG. 1

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]

3625

AND

POWERHALL

SENSOR/DRIVERS FOR

BRUSHLESS DC MOTORS

SENSOR LOCATION APPLICATIONS INFORMATION

Power Dissipation. Care should be taken in evaluating the package power

dissipation of these devices. Total power dissipated by the device will consist
of power due to the internal regulator, logic and drive circuitry (ICC x VCC),
power due to the output drivers (IO x V
circuitry (ICL x VCL x duty cycle).

For example:
ICC x VCC = 38 mA (max) x 14 V = 532 mW (max)

), and power due to the clamp

O(SAT)

3626

®

IO x V
ICL x VCL x duty cycle = 450 mA x 15 V (max) x 1% = 67.5 mW (max)

Some of the power dissipated by the device (ICC x VCC) can be reduced
by inserting a Zener diode in the supply line (ZA in the figure). Note that the
voltage at the VCC pin under worst-case conditions must be greater than the
minimum operating voltage (6.5 V).

Transient Protection. A note of caution concerns negative (below ground)
excursions of the outputs. In application, the coupling of the two motor
windings can provide for just such a case. Reducing the coupling between
windings will help, but ground clamp diodes or diodes in series with the
motor windings might be required (DC or DS in the figure). Most small
brushless motors will not require these diodes.

System requirements usually utilize a diode type of reverse-polarity
protection. If series diode protection is used with an inductive load (the usual
fan application), a Zener clamp between VS and ground (ZB in the figure) is
required. The Zener voltage must be greater than the supply voltage but less
than the rated maximum allowable supply voltage.

With diode reverse-polarity protection, a high-impedance supply, or a
switched supply line, high-voltage spikes will be generated (especially with
high-current or high-inductance loads) during normal operation, coasting, or
immediately after turn-off. In these situations, a Zener clamp (ZB) from VS to
ground will be required.

= 450 mA x 0.4 V (max) = 180 mW (max)

O(SAT)

Total package power dissipation = 779.5 mW (max)

Over-Current Adjust Pin. The over-current limit may be reduced from the
default value (IO MAX) by selection of an external resistor (R
PWM/IO ADJ pin.

ADJ

) at the

3625

POWERHALL

AND

3626

®

SENSOR/DRIVERS FOR
BRUSHLESS DC MOTORS

TYPICAL FAN APPLICATION

The external overcurrent adjust and the thermal shutdown are commoned
at the PWM/lO ADJ pin and tieing it to VCC will disable the thermal shut­down. PWM current/speed control can be performed at the PWM/lO ADJ pin
from a standard totem-pole logic output with a series Schottky diode
(1N5818,1N5819, or equivalent) or by pulling it low through an open­collector transistor (no pull-up resistor). PWM/lO ADJ input voltages greater
than 0.3 V are not recommended and may create an unstable operating
condition.

OUT ON/LOW

MAGNETIC FIELD

A

DEFINITIONS

+B

S

+B

N

Dwg. AP-001-1

-B

OUT ON/LOW

B

-B

O P

B = 0 G

By accepted magnetic convention, lines of flux emanate from the north pole of a magnet and enter the south pole.

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]

O P

Dwg. GP-008

+B

0.280

0.240

Dimensions in Inches

(controlling dimensions)

58

3625

AND

3626

POWERHALL

®

SENSOR/DRIVERS FOR

BRUSHLESS DC MOTORS

0.014

0.008

0.430

MAX

0.300

BSC

0.100

BSC

4

1

0.070

0.045

0.210

MAX

0.015

MIN

0.022

0.014

NOTES: 1. Leads 1, 4, 5, and 8 may be half leads at vendor’s option.

2. Lead thickness is measured at seating plane or below.

3. Lead spacing tolerance is non-cumulative.

4. Exact body and lead configuration at vendor’s option
within limits shown.

0.400

0.355

0.005

MIN

0.150

0.115

Dwg. MA-001-8A in

3625

POWERHALL

AND

3626

®

SENSOR/DRIVERS FOR
BRUSHLESS DC MOTORS

8

7.11

6.10

Dimensions in Millimeters

(for reference only)

5

0.355

0.204

7.62

BSC

10.92

MAX

1

4

1.77

1.15

10.16

9.02

5.33

MAX

0.39

MIN

0.558

0.356

NOTES: 1. Leads 1, 4, 5, and 8 may be half leads at vendor’s option.

2. Lead thickness is measured at seating plane or below.

3. Lead spacing tolerance is non-cumulative.

4. Exact body and lead configuration at vendor’s option
within limits shown.

2.54

BSC

0.13

MIN

3.81

2.93

Dwg. MA-001-8A mm

The products described herein are manufactured under one or
more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283;
5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719;
5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents
pending.

Allegro MicroSystems, Inc. reserves the right to make, from time to
time, such departures from the detail specifications as may be
required to permit improvements in the performance, reliability, or
manufacturability of its products. Before placing an order, the user is
cautioned to verify that the information being relied upon is current.

Allegro products are not authorized for use as critical components
in life-support appliances, devices, or systems without express written
approval.

The information included herein is believed to be accurate and
reliable. However, Allegro MicroSystems, Inc. assumes no responsi­bility for its use; nor for any infringements of patents or other rights of
third parties that may result from its use.

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]