ST L295 User Manual

L295

DUAL SWITCH-MODE SOLENOID DRIVER

■HIGH CURRENT CAPABILITY (up to 2.5A per channel)

■HIGH VOLTAGE OPERATION (up to 46V for power stage)

■HIGH EFFICIENCY SWITCHMODE OPERATION

■REGULATED OUTPUT CURRENT (adjustable)

■FEW EXTERNAL COMPONENTS

■SEPARATE LOGIC SUPPLY

■THERMAL PROTECTION

MULTIWATT15

ORDERING NUMBER: L295

DESCRIPTION

The L295 is a monolithic integrated circuit in a 15 -lead Multiwatt® package; it incorporates all the functions for direct interfacing between digital circuitry and inductive loads.

The L295 is designed to accept standard microprocessor logic levels at the inputs and can drive 2 solenoids. The output current is completely con-

trolled by means of a switch-ing technique allowing very efficient operation.

Furthermore, it includes an enable input and dual supplies (for interfacing with peripherals running at a higher voltage than the logic).

The L295 is particularly suitable for applications such as hammer driving in matrix printers, step motor driving and electromagnet controllers.

BLOCK DIAGRAM

							C
							R
							9
+VSS	10	VOLTAGE	THERMAL				OSCILLATOR
		REGULATOR	SHUTDOWN
+VS	1							1	+VS
		H2						H1
		DRIVER						DRIVER
D3	15							2	D1
	R2								R1
D4			LOGIC	R			R	LOGIC	D2
			CIRCUITS	Q			Q	CIRCUITS
	L2			FF2			FF2		L1
	14			S			S	3
		L2						L1
		DRIVER						DRIVER
RS2	13							4
VREF2	12							5	VREF1
				11	7	6		8
				Vin2	EN	Vin1		D03IN1503
October 2003									1/7

L295

ABSOLUTE MAXIMUM RATINGS

Symbol	Parameter	Value	Unit
VS	Supply voltage	50	V
VSS	Logic supply voltage	12	V
VEN, Vi	Enable and input voltage	7	V
Vref	Reference voltage	7	V
Io	Peak output current (each channel)
	- non repetitive (t = 100 msec)	3	A
	- repetitive (80% on - 20% off; Ton = 10ms)	2.5	A
	- DC operation	2	A
Ptot	Total power dissipation (at Tcase = 75 ²C	25	W
Tstg, Tj	Storage and junction temperature	- 40 to 150	°C

CONNECTION DIAGRAM

	15
	14
	13
	12
	11
	10
	9
	8
	7
	6
	5
	4
	3
	2
	1
TAB CONNECTED TO PIN 8	D03IN1502

OUTPUT H ch 2

OUTPUT L ch 2

CURRENT SENSING 2

REFERENCE VOLTAGE 2 INPUT 2

LOGIC SUPPLY VOLTAGE VSS

OSCILLATOR RC NETWORK GROUND

ENABLE

INPUT 1

REFERENCE VOLTAGE 1 CURRENT SENSING 1 OUTPUT L ch 1

OUTPUT H ch 1

SUPPLY VOLTAGE VS

THERMAL DATA

Symbol	Parameter	Value	Unit
Rth-j-case	Thermal resistance junction-case	max 3	°C/W
Rth-j-amb	Thermal resistance junction-ambient	max 35	°C/W

ELECTRICAL CHARACTERISTCS (Refer to the application circuit, Vss = 5V, Vs = 36V; Tj = 25°C; L = Low; H = High; unless otherwise specified)

Symbol	Parameter	Test Condition	Min.	Typ.	Max.	Unit
VS	Supply Voltage		12		46	V
VSS	Logic Supply Voltage		4.75		10	V
Id	Quiescent Drain Current	VS = 46V; Vi1 = Vi2 = VEN = L			4	mA
	(from VSS)
Iss	Quiescent Drain Current	VSS = 10V			46	mA
	(from VS)
Vi1,Vi2	Input Voltage	Low	-0.3		0.8	V
		High	2.2		7	V

2/7

L295

ELECTRICAL CHARACTERISTCS (continued)

Symbol

Parameter

Test Condition

Min.

Typ.

Max.

Unit

VEN

Enable Input Voltage

Low

-0.3

0.8

V

High

2.2

7

V

Ii1,Ii2

Input Current

Vi1 = Vi2 = L

-100

μA

Vi1 = Vi2 = H

10

μA

IEN

Enable Input Current

VEN = L

-100

μA

VEN = H

10

μA

Vref1,

Input Reference Voltage

0.2

2

V

Vref2

Iref1, Iref2

Input Reference Voltage

-5

μA

Fosc

Oscillator Frequency

C = 3.9 nF; R = 9.1 KΩ

25

46

KHz

Ip

Transconductance (each ch.)

Vref = 1V

1.9

2

2.1

A/V

Vref

Vref1,

Input Reference Voltage

0.2

2

V

Vref2

Vref1,

Input Reference Voltage

0.2

2

V

Vref2

Vdrop

Total Output Voltage

Io = 2 A

2.8

3.6

V

(each channel) (*)

Vsens1,

External sensing resistors voltage

2

V

Vsens2

drop

(*) Vdrop = VCEsat Q1 + VCEsat Q2.

APPLICATION CIRCUIT

+VS

C2

C4

15

1

2

0.1µF

220µF

R2

R1

D3

D4

D2

D1

L2

L1

+VSS

3

14

C1

10

9

0.1µF

8

R3

C3

7

6

5

4

9.1K

3.9nF

13

12

11

RS2

RS1

0.5Ω

0.5Ω

+VREF2

+VIN2

EN

+VIN1

+VREF1

D03IN1501

D2, D4 = 2A High speed diodes trr ≤ 200 ns

D1, D3 = 1A High speed diodes trr ≤ 200 ns

R1 = R2 = 2W

L1 = L2 = 5 mH

FUNCTIONAL DESCRIPTION

The L295 incorporates two indipendent driver channals with separate inputs and outputs, each capable of driving an inductive load (see block diagram). The device is controlled by three micriprocessor compatible digital inputs and two analog inputs.

3/7