L6221 STMICROELECTRONICS | Alldatasheet
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 22
Technical content
Datasheet sections
- 1 Thermal data
- 2 Pin information
- 3 Absolute maximum ratings
- 4 Electrical characteristics
- 5 Test circuits
- 6 Application information
- 7 Mounting instructions
- 8 Package mechanical data
- 9 Revision history
Features
■ Four non-inverting inputs with enable ■ Output voltage up to 50 V ■ Output current up to 1.8 A ■ Very low saturation voltage ■ TTL compatible inputs ■ Integral fast recirculation diodes
Applications
The L6221 monolithic quad Darlington switch is designed for high current, high voltage switching applications.
Description
Each of the four switches is controlled by a logic input and all four are controlled by a common enable input. All inputs are TTL-compatible for direct connection to logic circuits. Each switch consists of an open-collector Darlington transistor plus a fast diode for switching applications with inductive device loads. The emitters of the four switches are commoned. Any number of inputs and outputs of the same device may be paralleled. Figure 1. Block diagram Table 1. Device summary
1 Thermal data
Table 2. Thermal data
2 Pin information
Figure 2. Pin connections (top views)
Table 3. Truth table (1)
- For each input: H = High level, L = Low level
Table 4. Pin description (1)
- See Figure 1: Block diagram
3 Absolute maximum ratings
Table 5. Absolute maximum ratings
Electrical characteristics
4 Electrical characteristics
Note: Refer to the test circuits Figure 3 to Figure 10 (VS = 5 V, Tamb = 25 °C unless otherwise specified). Table 6. Electrical characteristics
5 Test circuits
Note: Pin numbers without parentheses apply to the Power DIP package. Pin numbers in parentheses are not applicable. Figure 3. Logic supply current Figure 4. Output sustaining voltage Figure 5. Output leakage current
Figure 18. Free-wheeling diode forward voltage against junction temperature
Application information
6 Application information
When inductive loads are driven by the L6221, a Zener diode in series with the integral free- wheeling diodes increases the voltage across which energy stored in the load is discharged and therefore speeds the current decay (Figure 19). For reliability it is suggested that the Zener is chosen so that There are two reasons for this:
- The Zener voltage changes in temperature and current.
- The instantaneous power must be limited to avoid the reverse second breakdown.
Figure 19. Free-wheeling diode connection when driving inductive loads current partitioning at turn-off. and the power stages (collector saturation voltage, free-wheeling diode forward voltage).
7 Mounting instructions
copper area of the printed circuit board (Figure 23) or to an external heat sink (Figure 24). Figure 23. Example of PCB copper area used as heat sink Figure 24. External heat sink mounting example
8 Package mechanical data
In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK® packages, depending on their level of environmental compliance. ECOPACK® specifications, grade definitions and product status are available at: www.st.com. ECOPACK® is an ST trademark.
DIM. mm inch a1 0.51 0.020 B 0.85 1.40 0.033 0.055 b 0.50 0.020 b1 0.38 0.50 0.015 0.020 D 20.0 0.787 E 8.80 0.346 e 2.54 0.100 e3 17.78 0.700 F 7.10 0.280 I 5.10 0.201 L 3.30 0.130 Z 1.27 0.050 Powerdip 16 OUTLINE AND MECHANICAL DATA Power DIP 16
Revision history
9 Revision history
Table 7. Document revision history Inserted title for Figure 19. 30-Mars-2009 4 Obsolete products E-L6221C/CD/CN added in Table 1.