tb62201afg TOSHIBA Semiconductor CORPORATION, tb62201afg Datasheet - Page 25

• Manufacturer Part Number: tb62201afg
• 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
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 4ïbit 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.
(2) Power consumed by the logic block and IM
The logic block is connected to V
current consumed by output switching) is connected to V
(3) Thus, power dissipation for 1 unit (P) is determined as follows by (2) and (3) above.
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.
The following standard values are used as power dissipation of the logic block and IM at operation.
P = P (out) + P (Logic & IM) = 1.51 (W)
P (out) = 2 (T
R
I
V
V
P (out) = 2 (T
I (LOGIC) = 2 mA (typ.): /unit
I (IM3) = 12.5 mA (typ.): operation/unit
I (IM1) = 6.0 mA (typ.): stop/unit
P (Logic & IM) = 5 (V) × 0.002 (A) + 24 (V) × 0.0125 (A) .................................... (3)
P (standby) = 24 (V) × 0.006 (A) + 5 (V) × 0.002 (A)
P (all) = 1.51 (W) + 1.664 (W) = 1.66 (W)
out
on
M
DD
= 24 V
= 0.6 Ω (@ 1.0 A)
(Peak: max) = 1.0 A
= 5 V
=1.20 (W)
= 0.154 (W)
r
r
) × I
) × 1.0 (A)^2 × 0.60 (Ω) ................................................................. (2)
= 0.31 (W)
out
(A) × V
DD
DS
(5 V). IM (total of current consumed by the circuits connected to V
(V) = 2 × I
out
^2 × R
25
M
on
(24 V). Power dissipation is calculated as follows :
......................................(1)
on
= 0.6 Ω)
TB62201AFG
2005-04-04
M
and