M48T212Y-85MH1(2000) Просмотр технического описания (PDF) - STMicroelectronics

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производитель

M48T212Y-85MH1
(Rev.:2000)

5V/3.3V TIMEKEEPER® CONTROLLER

STMicroelectronics 

M48T212Y, M48T212V

Table 7B. DC Characteristics for M48T212Y

(TA = 0 to 70°C; VCC = 4.5V to 5.5V)

Symbol

Parameter

Test Condition

Min

Typ

Max

Unit

ILI (1,2) Input Leakage Current

0V ≤ VIN ≤ VCC

±1

µA

ILO (1) Output Leakage Current

0V ≤ VOUT ≤ VCC

±1

µA

ICC Supply Current

Outputs open

8

15

mA

ICC1 Supply Current (Standby) TTL

E = VIH

5

mA

ICC2 Supply Current (Standby) CMOS

E = VCC –0.2

3

mA

Battery Current OSC ON

IBAT

Battery Current OSC OFF

575

800

nA

100

nA

VIL

Input Low Voltage

–0.3

0.8

V

VIH Input High Voltage

2.2

VCC + 0.3 V

Output Low Voltage

VOL

Output Low Voltage (open drain) (3)

IOL = 2.1mA

IOL = 10mA

0.4

V

0.4

V

VOH Output High Voltage

IOH = –1.0mA

2.4

V

VOHB (4) VOH Battery Back-up

IOUT2 = –1.0µA

2.0

3.6

V

IOUT1 (5) VOUT Current (Active)

VOUT1 > VCC –0.3

100

mA

IOUT2 VOUT Current (Battery Back-up)

VOUT2 > VBAT –0.3

100

µA

VPFD Power-fail Deselect Voltage

4.2

4.35

4.5

V

VSO Battery Back-up Switchover Voltage

3.0

V

VBAT Battery Voltage

3.0

V

Note: 1. Outputs deselected.

2. RSTIN1 and RSTIN2 internally pulled-up to VCC through 100KΩ resistor. WDI internally pulled-down to VSS through 100KΩ resistor.

3. For IRQ/FT & RST pins (Open Drain).

4. Conditioned outputs (E1CON - E2CON) can only sustain CMOS leakage currents in the battery back-up mode. Higher leakage cur-

rents will reduce battery life.

5. External SRAM must match TIMEKEE PER Controller chip VCC specification.

The M48T212Y/V also has its own Power-Fail De-

tect circuit. This control circuitry constantly moni-

tors the supply voltage for an out of tolerance

condition. When VCC is out of tolerance, the circuit

write protects the TIMEKEEPER register data and

external SRAM, providing data security in the

midst of unpredictable system operation. As VCC

falls, the control circuitry automatically switches to

the battery, maintaining data and clock operation

until valid power is restored.

Address Decoding

The M48T212Y/V accommodates 4 address lines

(A3-A0) which allow access to the sixteen bytes of

the TIMEKEEPER clock registers. All TIMEKEEP-

ER registers reside in the controller chip itself. All

TIMEKEEPER registers are accessed by enabling

E (Chip Enable).

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