ST L295 User Manual
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 PROT EC T I O N
L295
MULTIWATT1 5
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-
BLOCK DIAGRAM
10
1
15
14
13
12
VOLTAGE
REGULATOR
H2
DRIVER
L2
DRIVER
+V
SS
+V
S
D3
R2
D4
L2
R
S2
V
REF2
THERMAL
SHUTDOWN
LOGIC
CIRCUITS
RR
Q
FF2 FF2
SS
1176
trolled by means of a switch-ing techniq ue 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.
C
R
9
OSCILLATOR
1
H1
DRIVER
2
LOGIC
Q
CIRCUITS
L1
DRIVER
V
V
EN
in2
in1
D03IN1503
R1
L1
3
4
5
8
+V
S
D1
D2
V
REF1
October 2003
1/7
L295
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
V
V
SS
V
EN
V
ref
I
o
P
tot
T
stg
CONNECTION DIAGRAM
Supply voltage 50 V
S
Logic supply voltage 12 V
,
Enable and input voltage 7 V
V
i
Reference voltage 7 V
Peak output current (each channel)
- non repetitive (t = 100 µsec)
- repetitive (80% on - 20% off; T
- DC operation
Total power dissipation (at T
case
= 10ms)
on
= 75 ″C25W
3
2.5
2
, TjStorage and junction temperature - 40 to 150 °C
A
A
A
OUTPUT H ch 2
OUTPUT L ch 2
CURRENT SENSING 2
REFERENCE VOLTAGE 2
INPUT 2
LOGIC SUPPLY VOLTAGE V
OSCILLATOR RC NETWORK
GROUND
ENABLE
INPUT 1
REFERENCE VOLTAGE 1
CURRENT SENSING 1
OUTPUT L ch 1
OUTPUT H ch 1
SUPPLY VOLTAGE V
D03IN1502
SS
S
TAB CONNECTED TO PIN 8
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
THERMA L D ATA
Symbol Parameter Value Unit
R
th-j-case
R
th-j-amb
Thermal resistance junction-case
Thermal resistance junction-ambient
max 3
max 35
°C/W
°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
V
V
I
V
i1
Supply Voltage 12 46 V
S
Logic Supply Voltage 4.75 10 V
SS
Quiescent Drain Current
I
d
(from V
Quiescent Drain Current
ss
(from V
,
Input Voltage Low
V
i2
SS
S
)
)
V
= 46V; Vi1 = Vi2 = VEN = L 4 mA
S
V
= 10V 46 mA
SS
-0.3
High
2.2
0.8
7
V
V
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L295
ELECTRICAL CHARACTERISTCS (continued)
Symbol Parameter Test Condition Min. Typ. Max. Unit
V
I
i1
Enable Input Voltage Low
EN
,
Input Current Vi1 = Vi2 = L
I
i2
High
Vi1 = Vi2 = H
-0.3
2.2
0.8
7
-100
10
µA
µA
V
V
I
V
V
I
ref1
F
V
V
V
V
V
V
Enable Input Current VEN = L
EN
,
Input Reference Voltage 0.2 2 V
ref1
ref2
, I
Input Reference Voltage -5 µA
ref2
Oscillator Frequency C = 3.9 nF; R = 9.1 KΩ 25 46 KHz
osc
I
p
Transconductance (each ch.) V
ref
,
Input Reference Voltage 0.2 2 V
ref1
ref2
,
Input Reference Voltage 0.2 2 V
ref1
ref2
Total Output Voltage
drop
(each channel) (*)
V
,
External sensing resistors voltage
drop
= V
CEsat Q1
+ V
CEsat Q2
(*) V
sens1
V
sens2
drop
APPLICATION CIRCUIT
-100
= H
V
EN
= 1V 1.9 2 2.1 A/V
ref
I
o = 2 A
2.8 3.6 V
10
µA
µA
2V
.
+V
S
D2
D03IN1501
C2
0.1µF
D1
3.9nF
C3
+V
IN2
1
76
+V
EN
IN1
15
R2
D4
D3
L2
+V
SS
C1
0.1µF
10
8
13 12 11
R
S2
0.5Ω
+V
REF2
2
R1
L1
314
9
R3
9.1K
4
5
R
S1
0.5Ω
+V
REF1
C4
220µF
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.
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