PBL3776-1 Datasheet, PDF (1/8 Pages) Ericsson – Dual Controller IC for High Current Stepper Motor Applications

February 1999
PBL 3776/1
Dual Controller IC for High Current
Stepper Motor Applications
Description
The PBL 3776/1 is a switch-mode (chopper), constant-current controller IC intended
for controlling external transistors in a high current stepper motor application.The IC
has two channels one for each winding of a two-phase stepper motor. The circuit is
similar to Ericsson´s PBL 3775/1. PBL 3776/1 is equipped with a Disable input to
simplify half-stepping operation.
The PBL 3776/1 contains a clock oscillator, which is common for both driver
channels, a set of comparators and flip-flops implementing the switching control, and
two output sections each containing four outputs, two source and two sink, intended
to drive an external H-bridge.
Voltage supply requirements are +5 V for logic and +10 to +45 V for the outputs.
The close match between the two driver channels guarantees consistent output
current ratios and motor positioning accuracy.
Key Features
• Suitable to drive any external Mos Fet
or bipolar power transistor.
• 0°C to +85°C operation.
• Few external components.
• Crossconduction prevented by time
delay.
• Close matching between channels for
high positioning accuracy.
• Digital filter on chip eliminates
external
filtering components.
• Plastic 24-pin "narrow" DIP package.
Phase ₁
Dis ₁ V_R1
C1
SGND ₁
Pwr GND ₁
1
PBL 3776/1
V_CC
V
CC
–
+
RQ
S
Logic
+
–
RC
Logic
+
SQ
R
–
Phase ₂
Dis2 V_R2
C2
SGND ₂
Figure 1. Block diagram.
Pwr GND ₂
T1BL
T1AL
T1AU
T1BU
VBB1
PBL3776/1
V_BB2
T2BU
T2AU
T2AL
T2BL
24-pin plastic DIP package, narrow
1