DESCRIPTION APPLICATIONS FEATURES BLOCK DIAGRAM

PT5120
Stepping Motor Driver IC
DESCRIPTION
FEATURES
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The PT5120 is a PWM constant-current type stepping
motor driver IC designed for sinusoidal-input
micro-step control of stepping motors.
The PT5120 can be used in applications that require
2-phase, 1-2-phase, W1-2-phase and 2W1-2 phase
excitation modes. The PT5120 is capable of forward
and reverse driving of a 2-phase bipolar stepping
motor using only a clock signal.
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APPLICATIONS

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 DSLR
 Interchangeable Lens

Motor power supply voltage: VM = 15 V (max)
Control power supply voltage: VCC = 2.7 to 6 V
Output current: Iout ≤ 0.8 A (max)
Output ON-resistance: Ron = 1.5 Ω (upper and
lower [email protected] = 7 V)
Decoder that enables microstep control with the
clock signal
Selectable phase excitation modes (2, 1-2, W1-2
and 2W1-2)
Internal pull-down resistors on inputs: 200 KΩ
(typ.)
Output monitor pin (MO)
Thermal shutdown (TSD) and under voltage
lockout (UVLO) circuits
Small surface-mount package (TSSOP20 173mil:
0.65 mm lead pitch)
BLOCK DIAGRAM
GND
STBY
Vcc
15
2
1
MO
16
STANBY
UVLO
(2V)
M1
4
M2
5
Pre
Drive
+
-
H-Bridge
A
13
AO1
11
AO2
12
RFA
PWM
Timer
u step
Decoder
CW/CCW
7
CK
20
RESET
14
ENABLE
19
DCY
18
2
1-2
W1-2
2w1-2
Phase
TSD
B.G
TQ
OSC
Vref
2 switches
0.125V,0.5V
17
3
Pre
Drive
+
-
H-Bridge
B
6
VM
10
BO1
8
BO2
9
RFB
PWM
Timer
OSC
Tel: 886-66296288‧Fax: 886-29174598‧ http://www.princeton.com.tw‧2F, 233-1, Baociao Road, Sindian, Taipei 23145, Taiwan
PT5120
ORDER INFORMATION
Valid Part Number
Package Type
Top Code
PT5120-TX
TSSOP 20, 173mil
PT5120-TX
PIN CONFIGURATION
V1.1
2
September 2014
PT5120
PIN DESCRIPTION
Pin Name
VCC
I/O
Power
Supply
STBY
I
OSC
I
M1
I
M2
I
VM
Power
Supply
CW/CCW
I
BO2
O
RFB
O
BO1
O
AO2
O
RFA
O
AO1
O
RESET
I
GND
GND
MO
O
TQ
I
Description
Pin No.
Power supply pin for logic block
1
Standby input,
See the Input Signals and Operating Modes table.
Connection pin for an external capacitor used for internal oscillation
Excitation mode setting input 1,
See the Excitation Mode Settings table.
Excitation mode setting input 2,
See the Excitation Mode Settings table.
2
3
4
5
Power supply pin for output
6
Rotation direction select input,
See the Input Signals and Operating Modes table.
B-phase output 2,
Connect BO2 to a motor coil pin.
Connection pin for a B-phase output current detection resistor
B-phase output 1,
Connect BO1 to a motor coil pin.
A-phase output 2,
Connect AO2 to a motor coil pin.
Connection pin for an A-phase output current detection resistor
A-phase output 1
Connect AO1 to a motor coil pin.
Reset input
See the Input Signal and Operating Modes table.
Ground
7
8
9
10
11
12
13
14
15
Monitor output, Initial state: MO = Low (open drain, pulled up by an external
resistor)
Vref setting input
See the Vref Voltage Setting table.
16
17
Decay setting input,
DCY
I
ENABLE
I
CK
I
V1.1
See the Fast-Decay Time Inserted During the Current
Decay Period table.
Enable input,
See the Input Signal and Operating Modes table.
Clock input
3
18
19
20
September 2014
PT5120
IMPORTANT NOTICE
Princeton Technology Corporation (PTC) reserves the right to make corrections, modifications, enhancements,
improvements, and other changes to its products and to discontinue any product without notice at any time.
PTC cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a PTC product. No
circuit patent licenses are implied.
Princeton Technology Corp.
2F, 233-1, Baociao Road,
Sindian, Taipei 23145, Taiwan
Tel: 886-2-66296288
Fax: 886-2-29174598
http://www.princeton.com.tw
V1.1
29
September 2014