tb62202afg TOSHIBA Semiconductor CORPORATION, tb62202afg Datasheet - Page 24

• Manufacturer Part Number: tb62202afg
• Description: Dual-stepping Motor Driver Ic For Oa Equipment Using Pwm Chopper Type
• Manufacturer: TOSHIBA Semiconductor CORPORATION

IC Power Dissipation
IC power dissipation is classified into two: power consumed by transistors in the output block and power consumed
by the logic block and the charge pump circuit.
(1) Power consumed by the Power Transistor (calculated with R
(2) Power consumed by the logic block and IM
(3) Thus, power dissipation for 1 unit (P) is determined as follows by (2) and (3) above.
In Charge mode, Fast Decay mode, or Slow Decay mode, power is consumed by the upper and lower
transistors of the H bridges. The following expression expresses the power consumed by the transistors of a
H bridge.
The average power dissipation for output under 4-bit micro step operation (phase difference between
phases A and B is 90°) is determined by expression (1).
Thus, power dissipation for output per unit is determined as follows (2) under the conditions below.
The following standard values are used as power dissipation of the logic block and IM at operation.
The logic block is connected to V
and current consumed by output switching) is connected to V
follows:
Power dissipation for 1 unit at standby is determined as follows:
When one motor driving = 100 %, power dissipation is determined as follows:
For thermal design on the board, evaluate by mounting the IC.
P (out) = 2 (T
R
I
V
V
P (out) = 2 (T
I (LOGIC) = 2 mA (Typ.):
I (IM3) = 12.5 mA (Typ.): operation
I (IM1) = 6.0 mA (Typ.): stop
P (Logic and IM) = 5 (V) × 0.002 (A) + 24 (V) × 0.0125 (A) ....................... (3)
P = P (out) + P (Logic and IM) = 1.246 (W)
P (standby) = 24 (V) × 0.006 (A) + 5 (V) × 0.002 (A)
P (all) = 1.246 (W) + 0.154 (W) = 1.4 (W)
ou t
on
M
DD
= 24 V
= 1.3 Ω (@1.0 A)
(Peak : Max) = 0.6 A
= 5 V
= 0.936 (W)
= 0.154 (W)
r
r
) × I
) × 0.6 (A)^2 × 1.3 (Ω) ·················································(2)
= 0.31 (W)
out
(A) × V
/
DD
unit
DS
/
unit
(5 V). IM (total of current consumed by the circuits connected to V
(V) = 2 × I
/
unit
24
out
^2 × R
on
·························(1)
M
(24 V). Power dissipation is calculated as
on
= 1.3 Ω)
TB62202AFG
2005-04-04
M