ST L6227Q User Manual

Features

■ Operating supply voltage from 8 to 52 V

■ 2.8 A output peak current (1.4 A DC)

■ R

0.73 Ω typ. value @ TJ = 25 °C

DS(on)

■ Operating frequency up to 100 kHz

■ Non dissipative overcurrent protection

■ Dual independent constant t

PWM current

OFF

controllers

■ Slow decay synchronous rectification

■ Cross conduction protection

■ Thermal shutdown

■ Under voltage lockout

■ Integrated fast free wheeling diodes

Applications

■ Bipolar stepper motor

■ Dual or quad DC motor

L6227Q

DMOS dual full bridge driver

with PWM current controller

VFQFPN32 5 mm x 5 mm

Description

The L6227Q is a DMOS dual full bridge designed
for motor control applications, realized in
BCDmultipower technology, which combines
isolated DMOS power transistors with CMOS and
bipolar circuits on the same chip. The device also
includes two independent constant off time PWM
current controllers that performs the chopping
regulation. Available in VQFPN32 5 mm x 5 mm
package, the L6227Q features a non-dissipative
overcurrent protection on the high side power
MOSFETs and thermal shutdown.

Figure 1. Block diagram

VBOOT

VCP

EN

IN1

IN2

EN

IN1

IN2

V

BOOT

CHARGE

PUMP

OCD

A

THERMAL

PROTECTION

A

A

A

VOLTAGE

REGULATOR

5V10V

OCD

B

B

B

B

OVER

CURRENT

DETECTION

GATE

LOGIC

OVER

CURRENT

DETECTION

GATE

LOGIC

V

BOOT

10V 10V

ONE SHOT

MONOSTABLE

MASKING

PWM

TIME

V

BOOT

SENSE

COMPARATOR

BRIDGE A

BRIDGE B

+

-

D99IN1085A

VS

A

OUT1

OUT2

SENSE

VREF

RC

A

V

S

B

OUT1

OUT2

SENSE

VREF

RC

B

A

A

A

A

B

B

B

B

January 2009 Rev 3 1/27

www.st.com

27

Contents L6227Q

Contents

1 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.1 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2 Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.3 Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2 Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4 Circuit description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.1 Power stages and charge pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.2 Logic inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

4.3 Truth table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.4 PWM current control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.5 Slow decay mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4.6 Non-dissipative overcurrent protection . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4.7 Thermal protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

5 Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

6 Output current capability and IC power dissipation . . . . . . . . . . . . . . 21

7 Thermal management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

8 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

9 Order codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

10 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2/27

L6227Q Electrical data

1 Electrical data

1.1 Absolute maximum ratings

Table 1. Absolute maximum ratings

Symbol Parameter Parameter Value Unit

V

V

V

BOOT

V

IN,VEN

V

REFA

V

RCA, VRCB

V

SENSEA,

V

SENSEB

I

S(peak)

T

stg

OD

, V

I

, T

S

S

Supply voltage

Differential voltage between
VSA, OUT1A, OUT2A, SENSEA and

, OUT1B, OUT2B, SENSE

VS

B

B

Bootstrap peak voltage

Input and enable voltage range -0.3 to +7 V

Voltage range at pins V

REFB

V

REFB

REFA

and

Voltage range at pins RCA and RC

Voltage range at pins SENSEA and
SENSE

B

Pulsed supply current (for each VS
pin), internally limited by the
overcurrent protection

RMS supply current (for each VS pin)

Storage and operating temperature

OP

range

B

VSA =

VSB = V

VSA =

VSB = VS = 60 V;

V

VSA =

VSA =
t

PULSE

VSA =

SENSEA

VSB = V

VSB = VS;

< 1 ms

VSB = V

= V

S

SENSEB

S

S

1.2 Recommended operating conditions

= GND

60 V

60 V

VS + 10 V

-0.3 to +7 V

-0.3 to +7 V

-1 to +4 V

3.55 A

1.4 A

-40 to 150 ° C

Table 2. Recommended operating conditions

Symbol Parameter Parameter Min Max Unit

V

REFA

V

V

V

S

V

OD

, V

SENSEA,

SENSEB

I

OUT

T

J

f

sw

Supply voltage

Differential voltage between

, OUT1A, OUT2A, SENSEA and

VS

A

VSB, OUT1B, OUT2B, SENSE

Voltage range at pins V

REFB

V

REFB

Voltage range at pins SENSEA and
SENSE

B

REFA

B

and

VSA =

VSB = V

VSA =

VSB = VS;

V

SENSEA

= V

SENSEB

(pulsed tW < trr)
(DC)

S

852V

-0.1 5 V

-6

-1

RMS output current 1.4 A

Operating junction temperature -25 +125 °C

Switching frequency 100 kHz

3/27

52 V

6
1

V
V

Electrical data L6227Q

1.3 Thermal data

Table 3. Thermal data

Symbol Parameter Value Unit

R

th(JA)

1. Mounted on a double-layer FR4 PCB with a dissipating copper surface of 0.5 cm2 on the top side plus 6
cm2 ground layer connected through 18 via holes (9 below the IC).

Thermal resistance junction-ambient max

(1)

.

42 ° C/W

4/27

L6227Q Pin connection

2 Pin connection

Figure 2. Pin connection (top view)

Note: 1 The pins 2 to 8 are connected to die PAD

2 The die PAD must be connected to GND pin

5/27

Pin connection L6227Q

Table 4. Pin description

N° Pin Type Function

1, 21 GND GND Signal ground terminals.

9OUT1BPower output Bridge B output 1.

11 RC

B

RC pin

RC network pin. A parallel RC network connected between this pin and
ground sets the current controller OFF-time of the bridge B.

12 SENSE

13 IN1

14 IN2

B

B

15 VREF

Power supply

B

Logic input Bridge B input 1

Logic input Bridge B input 2

Analog input

B

Bridge B source pin. This pin must be connected to power ground through a
sensing power resistor.

Bridge B current controller reference voltage.
Do not leave this pin open or connect to GND.

Bridge B enable. LOW logic level switches OFF all power MOSFETs of bridge
B. This pin is also connected to the collector of the overcurrent and thermal

16 EN

B

Logic input

(1)

protection transistor to implement over current protection.
If not used, it has to be connected to +5 V through a resistor.

17 VBOOT

19 OUT2

20 VS

22 VS

B

A

23 OUT2

Supply
voltage

Power output Bridge B output 2.

B

Power supply

Power supply

Power output Bridge A output 2.

A

Bootstrap voltage needed for driving the upper power MOSFETs of both
bridge A and Bridge B.

Bridge B power supply voltage. It must be connected to the supply voltage
together with pin VS

.

A

Bridge A power supply voltage. It must be connected to the supply voltage
together with pin VS

.

B

24 VCP Output Charge pump oscillator output.

Bridge A enable. LOW logic level switches OFF all power MOSFETs of bridge
A. This pin is also connected to the collector of the overcurrent and thermal

25 EN

A

Logic input

(1)

protection transistor to implement over current protection.
If not used, it has to be connected to +5 V through a resistor.

26 VREF

27 IN1

28 IN2

29 SENSE

30 RC

31 OUT1

1. Also connected at the output drain of the over current and thermal protection MOSFET. Therefore, it has to be driven

putting in series a resistor with a value in the range of 2.2 kΩ - 180 kΩ, recommended 100 kΩ.

Analog input

A

Logic input Bridge A logic input 1.

A

Logic input Bridge A logic input 2.

A

Power supply

A

A

A

RC pin

Power output Bridge A output 1.

Bridge A current controller reference voltage.
Do not leave this pin open or connect to GND.

Bridge A source pin. This pin must be connected to power ground through a
sensing power resistor.

RC network pin. A parallel RC network connected between this pin and
ground sets the current controller OFF-time of the bridge A.

6/27

L6227Q Electrical characteristics

3 Electrical characteristics

Table 5. Electrical characteristics (TA = 25 °C, Vs = 48 V, unless otherwise specified)

Symbol Parameter Test condition Min Typ Max Unit

V

Sth(ON)

V

Sth(OFF)

I

T

J(OFF)

S

Turn-on threshold 5.8 6.3 6.8 V

Turn-off threshold 5 5.5 6 V

Quiescent supply current

All Bridges OFF;

= -25 °C to 125 °C

T

J

(1)

510mA

Thermal shutdown temperature 165 ° C

Output DMOS transistors

= 25 °C 1.47 1.69 Ω

T

R

DS(on)

I

DSS

High-side + low-side switch ON
resistance

Leakage current

J

T

=125 ° C

J

EN = Low; OUT = V

(1)

2.35 2.7 Ω

S

2mA

EN = Low; OUT = GND -0.3 mA

Source drain diodes

V

SD

t

rr

t

fr

Forward ON voltage ISD = 1.4 A, EN = LOW 1.15 1.3 V

Reverse recovery time If = 1.4 A 300 ns

Forward recovery time 200 ns

Logic input

V

V

I

I

V

th(ON)

V

th(OFF)

V

th(HYS)

IL

IH

IL

IH

Low level logic input voltage -0.3 0.8 V

High level logic input voltage 2 7 V

Low level logic input current GND logic input voltage -10 µA

High level logic input current 7 V logic input voltage 10 µA

Turn-on input threshold 1.8 2.0 V

Turn-off input threshold 0.8 1.3 V

Input threshold hysteresis 0.25 0.5 V

Switching characteristics

t

D(on)EN

t

D(on)IN

t

RISE

t

D(off)EN

t

D(off)IN

t

FAL L

t

dt

f

CP

Enable to out turn ON delay time

Input to out turn ON delay time

Output rise time

Enable to out turn OFF delay time

Input to out turn OFF delay time I

Output fall time

Dead time protection 0.5 1 µs

Charge pump frequency

(2)

(2)

(2)

I

=1.4 A, resistive load 500 800 ns

LOAD

I

=1.4 A, resistive load

LOAD

(dead time included)

I

LOAD

(2)

I

LOAD

LOAD

I

LOAD

=1.4 A, resistive load 40 250 ns

=1.4 A, resistive load 500 800 1000 ns

=1.4 A, resistive load 500 800 1000 ns

=1.4 A, resistive load 40 250 ns

1.9 µs

-25 °C < TJ < 125 °C 0.6 1 MHz

7/27

Electrical characteristics L6227Q

Table 5. Electrical characteristics (continued) (TA = 25 °C, Vs = 48 V, unless otherwise specified)

Symbol Parameter Test condition Min Typ Max Unit

PWM comparator and monostable

I

RCA, IRCB

V

offset

t

PROP

t

BLANK

t

ON(MIN)

t

OFF

I

BIAS

Source current at pins RCA and RC

Offset voltage on sense comparator V

Turn OFF propagation delay

(3)

Internal blanking time on SENSE pins 1 µs

Minimum on time 2.5 3 µs

PWM recirculation time

Input bias current at pins VREFA and
VREFB

V

B

= V

RCA

REFA, VREFB

R

= 20 kΩ; C

OFF

= 100 kΩ; C

R

OFF

= 2.5 V 3.5 5.5 mA

RCB

= 0.5 V ±5 mV

= 1 nF 13 µs

OFF

= 1 nF 61 µs

OFF

Over current protection

I

SOVER

R

OPDR

t

OCD(ON)

t

OCD(OFF)

1. Tested at 25 °C in a restricted range and guaranteed by characterization.

2. See Figure 3 on page 9

3. Measured applying a voltage of 1 V to pin SENSE and a voltage drop from 2 V to 0 V to pin VREF.

4. See Figure 4 on page 9

Input supply overcurrent protection
threshold

Open drain ON resistance I = 4 mA 40 60 Ω

OCD turn-on delay time

OCD turn-off delay time

(4)

(4)

= -25 °C to 125 °C

T

J

I = 4 mA; CEN < 100 pF 200 ns

I = 4 mA; CEN < 100 pF 100 ns

(1)

500 ns

10 µA

2.8 A

8/27

L6227Q Electrical characteristics

Figure 3. Switching characteristic definition

EN

V

th(ON)

V

th(OFF)

t

I

OUT

90%

10%

D01IN1316

t

D(OFF)EN

t

FALL

t

D(ON)EN

t

t

RISE

Figure 4. Overcurrent detection timing definition

I

OUT

I

SOVER

ON

BRIDGE

OFF

V

EN

90%

10%

t

OCD(ON)

t

OCD(OFF)

D02IN1399

9/27