Datashett De 556

TS556
Low-power dual CMOS timer
Features
■

Very low power consumption: 220 µA typ at VCC = 5 V 180 µA typ at VCC = 3 V High maximum astable frequency 2.7 MHz Pin-to-pin and functionally compatible with bipolar NE556 Wide voltage range: 2 V to 16 V Supply current spikes reduced during output transitions High input impedance: 1012 Ω Output compatible with TTL, CMOS and logic MOS D SO14(Plastic micropackage) N DIP14 (Plastic package)

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Description
The TS556 is a dual CMOS timer which offers a very low consumption: (Icc(TYP) TS556 = 220 µA at VCC = +5 V versus Icc(TYP) NE556 = 6 mA), and high frequency: (f(max.) TS556 = 2.7 MHz versus f(max.) NE556 = 0.1 MHz). In both monostable and astable modes, timing remains very accurate. The TS556 provides reduced supply currentspikes during output transitions, which enable the use of lower decoupling capacitors compared to those required by bipolar NE556. Due to the high input impedance (1012Ω), timing capacitors can also be minimized. Pin connections (top view)

Discharge Threshold Control Voltage Reset Output Trigger GND

1 2 3 4 5 6 7

14 13 12 11 10 9 8

+VS Discharge Threshold Control Voltage Reset OutputTrigger

October 2008

Rev 2

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Absolute maximum ratings and operating conditions

TS556

1

Absolute maximum ratings and operating conditions
Table 1.
Symbol VCC IOUT Rthja Supply voltage Output current Thermal resistance junction to ambient DIP14 (1) SO14 (2) Thermal resistance junction to case DIP14(1) SO14(2) Junction Temperature Storage Temperature RangeHuman body model ESD (HBM)(3)

Absolute maximum ratings
Parameter Value +18 ± 100 80 105 33 31 +150 -65 to +150 1200 200
(5)

Unit V mA °C/W

Rthjc Tj Tstg

°C/W °C °C

Machine model (MM)(4) Charged device model (CDM)

V

1000

1. Short-circuits can cause excessive heating. These values are typical and specified for a single layer PCB. 2. Short-circuits can cause excessive heating.These values are typical and specified for a four layers PCB. 3. Human body model: a 100 pF capacitor is charged to the specified voltage, then discharged through a 1.5kΩ resistor between two pins of the device. This is done for all couples of connected pin combinations while the other pins are floating. 4. Machine model: a 200 pF capacitor is charged to the specified voltage, then dischargeddirectly between two pins of the device with no external series resistor (internal resistor < 5 Ω). This is done for all couples of connected pin combinations while the other pins remain floating. 5. Charged device model: all pins plus package are charged together to the specified voltage and then discharged directly to the ground.

Table 2.
Symbol VCC IOUT

Operating conditions
Parameter Supplyvoltage Output sink current Output source current Operating free air temperature range: TS556C TS556I TS556M Value 2 to 16 10 50 0 to +70 -40 to +125 -55 to +125 Unit V mA

Toper

°C

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Figure 1.

TS556

V CC

R1 Τ1 Τ21 Τ20 Τ26 Τ27 Τ30 Τ31 Τ11 Τ2 Τ12 Τ13 Τ10

50k Ω

Schematic diagram

R2

50k Ω R7 Threshold Τ8 Τ9 Τ4 Τ25

Τ34

Control Voltage

Schematic diagram(1/2 TS556)

R3

50k Ω Output Trigger Τ14 Τ18 Τ7 Τ23 Τ24 Τ19 Τ28 Τ29 Τ32 Discharge Τ35

R4

50k Ω Τ5 Τ6

R5

50k Ω

R6 Τ15 Τ16

Τ17 Τ22 Τ33

50k Ω

Schematic diagram

GND

RESET

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Schematic diagram Figure 2. Block diagram
V CC
14

TS556

Reset
4 / 10 TS556

R
2 / 12

R1
+

Threshold Control Voltage

Q R
5/9

Output

3 / 11

A S

R
+Trigger

6/8

-

B
1 / 13

R
7

Discharge

Ground

Table 3.

Functions table
Reset Low High High High Trigger x Low High High Threshold x x High Low Output Low High Low Previous State

Note:

LOW: level voltage ≤ minimum voltage specified HIGH: level voltage ≥ maximum voltage specified x: irrelevant.

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TS556

Electrical characteristics

3

Electrical...