mm1538 Mitsumi Electronics, Corp., mm1538 Datasheet - Page 22

• Manufacturer Part Number: mm1538
• Description: 4-ch Motor Driver For Portable Cd Players
• Manufacturer: Mitsumi Electronics, Corp.

MITSUMI
(5) Over voltage protection circuit
4 Empty detector block
(1) Output voltage
5 Reset circuit block
6 Charging circuit block
· When the voltage applied to BSEN(1PIN)reaches 8.4V typ. , SPRT(8PIN)is charged, and when the voltage
· When the voltage applied to the BSEN(1PIN)falls below the detector voltage, EMP(35PIN)goes from high
· At about 90% typ. of the DC-DC converter output voltage, RESET(3PIN)goes from low level to high level,
· The power supply for the charging circuit block is CHGV
· A thermal shutdown circuit is provided,and when the chip temperature reaches 150°C typ. the charging
SEL
L
High-Z
reaches 1.2V typ. , theSW(5PIN)switching stops. The time until switching stops is set by the capacitor
connected to SPRT(8PIN)according to the following formula.
level to low level(open-collector output). The detector voltage has 50mV typ. of hysteresis to prevent
output chattering. Use SEL(42PIN)to switch the detection voltage as shown below.
and AMUTE(34PIN)goes from high level to low level. The reset voltage has 50mV typ. of hysteresis to
prevent output chattering.
circuits.The resistance between RCHG(33PIN)and GND sets the charging current. This current is drawn
from SEL(42PIN).
current is cut. The chip starts operating again at about 120°C typ. .
t=CSPRT
Detect Voltage
2.20V typ.
1.80V typ.
IHV
V
TH
(sec) (V
TH
Return Voltage
=1.2V, I
2.25V typ.
1.85V typ.
HV
=20µA)
4-ch Motor Driver for Portable CD Players MM1538
CC
(41PIN), and is independent from the other